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Synthesis and characterization of regular segmented copolymers of poly(pivalolactone) and poly(oxyethylene)

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Synthesis and characterization of regular segmented copolymers of poly(pivalolactone) and poly(oxyethylene)
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Matayabas, James Christopher, 1961-
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English
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vii, 113 leaves : ill. ; 29 cm.

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Calibration ( jstor )
Copolymers ( jstor )
Flasks ( jstor )
Furans ( jstor )
Integers ( jstor )
Molecular weight ( jstor )
Oxides ( jstor )
Polymerization ( jstor )
Polymers ( jstor )
Potassium ( jstor )
Block copolymers ( lcsh )
Chemistry thesis Ph. D
Dissertations, Academic -- Chemistry -- UF
Organic compounds -- Synthesis ( lcsh )
Poly(oxyethylene) ( lcsh )
Poly(pivalolactone) ( lcsh )
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bibliography ( marcgt )
non-fiction ( marcgt )

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Thesis:
Thesis (Ph. D.)--University of Florida, 1991.
Bibliography:
Includes bibliographical references (leaves 92-95)
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Typescript.
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Vita.
Statement of Responsibility:
by James Christopher Matayabas.

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University of Florida
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Copyright [name of dissertation author]. Permission granted to the University of Florida to digitize, archive and distribute this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
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MSYNTHESIS AND CHARACTERIZATION OF REGULAR SEGMENTED COPOLYMERS OF POLY (PIVALOLACTONE) AND POLY(OXYETHYLENE) BY JAMES CHRISTOPHER MATAYABAS, JR. :.?*..' -•-% %. ?•' -'_ %. % %': \ A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF .^ DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA "^' '^-'--^'"' . :-:'. 1991 V. ^^"';^'= , V "^r^

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'T^; 4f,: To my wife, Deborah, and son, Joseph Johnson, for their patience, understanding, support, and, most importantly, their love. •1-,: 1

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ACKNOWLEDGMENTS Support for this study was provided by the Army Research Office. The preparation procedures and samples of 2-benzoxyethanol and 2-(dimethylthexylsiloxy)ethanol were donated by Dr. Mattson of the University of South Florida. Pivalolactone was donated by Dr. H. K. Hall of the University of Arizona. Narrow molecular weight distribution poly(oxyethylene) glycol, PEG(IOOO), was donated by Dr. S. K. Verma of Union Carbide. I thank my supervisory committee for their contribution to my education, with special thanks to Dr. William M. Jones. I thank R. W. Moshier and R. Stroschein of the University of Florida Glass Shop for their excellent craftsmanship. I thank Jason Portmess for his assistance in the laboratory . ' • •'' I am proud to have been a member of the University of Florida Center for Macromolecular Science and Engineering, more commonly known as the Polymer Floor. Special thanks go to the Polymer Floor secretaries, Loraine Williams and Pat Hargraves. ;, -,«.^ Special thanks go to Dr. Kenneth B. Wagener for the encouragement and guidance he has given me in his warm and friendly manner. v i j iii rm^

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TABLE OF CONTENTS ACKNOWLEDGMENTS iii ABSTRACT vi INTRODUCTION 1 Segmented Copolymers 1 Microphase Separation 3 Poly(pivalolactone) 5 Thermoplastic Elastomers with a Poly (pivalolactone) Hard Segment 8 Objectives of This Dissertation 13 EFFECT OF HARD-SEGMENT LENGTH ON MICROPHASE SEPARATION 15 Introduction 15 Materials 16 Synthesis 16 Determination of Molecular Weight 17 Determination of Intrinsic Viscosity 20 Determination of Mark-Houwink Parameters ... 20 Viscosity Measurements in Other Solvents ... 23 Analysis of Microphase Separation 23 Analysis of the Soft Phase 25 Soft-Segment Segregation 28 Determination of the Hard-Phase Composition . 30 Chapter Summary 34 SYNTHESIS OF DEFECT-FREE TELECHELOMERS 35 Introduction 35 Siloxy-Protected Initiator 35 Synthesis 36 Polymerization 36 Hydroxy Acid Initiators 42 Introduction 42 Initial Attempts 43 Synthesis of Defect-Free Telechelomers 45 Formation of Dianionic Initiator 45 Dual Anionic Polymerization 49 Sequential Addition Polymerization 52 Control of the Soft-Segment Length 52 Control of the Hard-Segment Length 57 Analysis of Microphase Separation 59 Chapter Summary 62 . : " : '-. ^*"->...v.':' ' '"''"-: _

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STEP POLYMERIZATION OF TELECHELOMERS 63 Introduction 63 Model Study 65 Melt Esterif ication of Telechelomers 69 Chapter Summary 72 EXPERIMENTAL 75 Instrumentation 75 SEC Programs 79 General Description 79 Calibration 79 Sample Analysis 81 Chemicals 81 Syntheses 83 Synthesis of 7 83 Synthesis of 8 84 Synthesis of (PVL)in-(OE)n-(PVL)jn 85 Synthesis of 10 86 Synthesis of 11 86 Synthesis of 12 87 Synthesis of 13. 87 Synthesis of 14 88 Synthesis of jL6 88 General Procedure for Dual-Anionic Polymerization 89 General Procedure for Sequential Addition Polymerization ... 90 General Procedure for Alanine-Mediated Step Polymerization . . 91 REFERENCES ,*^ ^^ a»-^ 92 APPENDIX . . . ." .• . :|4,.|.f .1 4L. » L 96 BIOGRAPHICAL SKETCH , * 112 0''-^ '-^ ^v -Vr*-.-i'

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Abstract of Dissertation Presented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy SYNTHESIS AND CHARACTERIZATION OF REGULAR SEGMENTED COPOLYMERS OF POLY (PIVALOLACTONE) AND POLY(OXYETHYLENE) -".;.;v'. , m >.v;: JAMES CHRISTOPHER MATAYABAS, JR. . ,.,:., May 1991 Chairman: Kenneth B. Wagener Major Department: Chemistry ,...». Microphase separation in a series of triblock poly(pivalolactoneblock -oxyethyleneblock -pivalolactone) oligomers, represented by (PVL)jn-(OE) 24-(PVL)jn, where m = 5, 7, 9, 12, 16, and 24, was investigated by differential scanning calorimetry. With the poly(pivalolactone) hardsegment length maintained at 24 repeat units, a very distinct transition from phase mixed to essentially complete microphase separation occurs when m is increased from 9 to 12. Complete microphase separation occurs for m = 16. Defect-free poly (oxyethylene-block-pivalo lactone) telechelomers, represented by (OE) 34-(PVL)i„, where m = 5, 12, and 16, were synthesized by sequential anionic ringopening polymerization of ethylene oxide and pivalolactone with hydroxypivalic acid. These telechelomers exhibited excellent microphase separation, allowing both the hard and VI

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soft segments to crystallize. Essentially complete microphase separation occurs for m = 12 and 16, and the sample with m = 5 showed some microphase mixing in the hard phase. Step polymerization of the (OE) 34-(PVL)jn telechelomers was achieved by alanine-mediated melt esterif ication with a titanium tetrabutoxide added in catalytic amounts, producing low molecular weight segmented copolymers, represented by [ (OE) 34-(PVL)in]p. Melt esterif ication of the sample with m = 16 produced the pentamer, [ (OE) 34-(PVL) ^gls, with M^ = 16,000 g/mole. Alanine-mediated step polymerization was investigated in a model study involving a-hydroxypoly(pivalolactone) telechelomers; however, only dimers were produced. -.; -'' .-' / »% y** •'-* -^^ '•^^ r \ /-*. *-i'v /' Vll

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INTRODUCTION xi,:-' • : -fSecfinented Copolymers Block copolymers can be envisioned as polymers composed of two or more homopolymers joined at the ends. If homopolymer A and homopolymer B are linked together by a chemical bond, the resulting structure is a diblock copolymer, A-B: aaaaa-bbbbb where "a" represents the repeat unit of homopolymer A, and "b" represents the repeat unit of homopolymer B. The addition of a third block produces a triblock copolymer, either A-B-A or B-A-B: aaaaa-bbbbb-aaaaa or bbbbb-aaaaa-bbbbb The coupling of four or more blocks together forms a segmented copolymer [A-Bj^s [ aaaaa-bbbbb] 3j Block and segmented copolymers are of great interest due to the unusual properties that may result, and McGrath^ has edited an excellent overview of block and segmented copolymers. While properties that are dependent upon the chemical nature of the segments — for example, chemical resistance, stability, and electrical properties — are generally unaffected, the block architecture has a strong influence on the mechanical properties of the copolymer — for ^ V,. 1

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2 example, elasticity and toughness. McGrath points out that the interesting characteristic of segmented copolymers is the strong repulsion between unlike segments that causes like segments to segregate into two-phase physical networks. There are a number of segmented copolymer systems which are one phase at temperatures well above the melt but exhibit phase separation upon cooling, resulting in a wide variety of useful materials ranging from impact-resistant polymers to elastomers. Thermoplastic elastomers, which combine thermoplasticity with rubber behavior, have received the greatest attention. Schollenberger and Scott^ first discovered poly(urethane ether) thermoplastic elastomers in 1958, and poly(urethane ethers) remain active subjects of investigation.^"^ Poly(urethane ethers) typically are synthesized by step copolymerization of an aryldiisocyanate with an alkyldiol in the presence of a poly (ether) glycol. Poly(ester ether) thermoplastic elastomers, which appeared more recently, are synthesized by analogous polyesterif ication reactions of an aryldiester — or acid derivative — with an akyldiol and poly (ether) glycol. ^"^5 since the development of living anionic chain polymerization, block copolymers can be synthesized by the sequential addition of two or more monomers; however, this technique is only practical for the synthesis of diblock and triblock copolymers. Prud'homme^^ used this technique to synthesize poly ( styreneblock isoprene) copolymers for a study of microphase separation.

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:-^•>'f^^*^'^^H "V';'>"i'wt-r~j-,v^5(m» V, . ' . ^. , ; / 3 /,/ '.y'^C Recently, these general techniques have been combined to synthesize a variety of block, segmented, and graft copolymers, and this is the topic of recent and future symposia. ^^ :-.-"" Microphase Separation In general, multiphase thermoplastic elastomers contain a soft segment and an incompatible hard segment. The soft segments segregate to form an amorphous or semicrystalline soft phase, and the hard segments segregate to form a crystalline hard phase, which acts as a thermally labile physical crosslink. These segments are chemically bonded, and even complete segregation cannot lead to macroscopic phase separation as is found in homopolymer blends. Instead, microphase separation occurs where there is sufficient incompatibility between segments. V, .. ., The simplified two-dimensional drawing of the microphase separation of the hard and soft phases of an oriented segmented copolymer given in Figure 1 offers a pictorial representation of microphase separation. In reality, monomer concentrations vary smoothly over the entire microphase structure, ^^' ^^ in contrast to the abrupt changes in concentration associated with a clearly defined interface depicted in Figure 1, v t >-. iij, i. Differential scanning calorimetry (DSC) has proven useful in the study or microphase separation, demonstrating that phase separation usually is incomplete. •'"^ The degree of microphase mixing in multiphase copolymers is of great concern since it reduces the effectiveness of the physical

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\{ J t> ' ; f^ ^« MM r^ • » 4 -^#'r* rf-^ Soft Segment Rich Soft Phase Hard Segment Rich Hard Phase Figure 1. Representation of the Microphase Separation in an Oriented Segmented Copolymer. ';\'^ "

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': . ;;:_. .. 5 crosslink and, therefore, adversely affects the properties of the copolymer — such as immediate elastic recovery, stress decay, and compression set (each indicating the ability of the polymer to return to its original condition after a stress has been applied to it) . Factors known to enhance microphase separation include a narrow molecular weight distribution, -^' ^2,13,20 ^ sufficient hard-segment length to permit crystallization, ^'^'^^ and a sufficient soft-segment length. ^i Wolfe^"-^^ carried out extensive studies of structure/property relationships for poly (ester ether) thermoplastic elastomers, and he found that these materials ranged from impact resistant plastics to elastomers, depending upon the nature and length of the poly (ester) hard segment and depending upon the poly (ether) soft-segment length. Polv (pivalolactone) Pivalolactone, 2,2-dimethyl-/3-propiolactone, reacts at either of two sites in the molecule. Yamashita and coworkers22f23 investigated pivalolactone polymerization and found that strong nucleophiles attack the carbonyl group with acyl-oxygen fission, resulting in an alkoxide propagating species; however, attempts to polymerize pivalolactone with an alkoxide terminated poly (oxytetramethlyene) initiator produced homopoly (pivalolactone) due to an unknown chain transfer reaction following the acyl-oxygen cleavage. Jedlinski^* achieved polymerization of pivalolactone in tetrahydrofuran by exposure to 18-crown-6 and potassium

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^. _.. 6 metal in which the initial step of polymerization involved attack at the methylene with cleavage of the 2,3-carboncarbon bond. Lenz^S, and Hall^^^ and Beaman^^ investigated pivalolactone polymerization and showed that the less nucleophilic carboxylate anion is preferable in polymerizing pivalolactone smoothly. Carboxylate salts attack pivalolactone at the methylene carbon, opening the ring with acyloxygen cleavage (3^2) to form a carboxylate propagating species (Figure 2) . Carboxylate salts give fairly rapid polymerization of pivalolactone in tetrahydrofuran and acetonitrile with a linear relationship between polymer molecular weight and percent conversion. The rate of initiation by tetramethylammonium acetate is equal to the rate of polymerization in acetonitrile. When tetraethylammonium pivalate is used as the initiator, polymerization proceeds at the same rate, but the rate of initiation is 160% faster. Therefore, narrow molecular weight distribution polymers are obtained, and the molecular weight is controlled by the stoichiometric ratio of initiator to monomer. Polymerization with carboxylates result in living polymers, and no termination or chain transfer occurs. High molecular weight poly (pivalolactone) is a highly crystalline polymer that exists in three crystalline modifications described by Osterhof^S, and Borri^^, and Prud'homme.20 The a-form, the main product that crystallizes from the melt, has large lamellae, 120-180 A, a

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R-C-O •T,'-' -\'-'^ n II RCO— CHgClCHgJa CO" n-1 ' — o O II R-CO II O— CH2C(CH3)2C-|O" n Figure 2. Initiation and Polymerization of Pivalolactone by Carboxylate Initiator. i V f ; .^•^.: u .V* -V :* w rr'vii-'H * ; ^ .A I. f%

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melting point temperature in the range 230-240'C, and a glass transition temperature of -10 °C for the amorphous regions. The )3-form results from very slow cooling from the melt and has a slightly lower melting point. The gammaform, which results from rapid cooling from the melt, melts in the range 210-220°C, and Geil and coworkers^ ^ showed that lamellar single crystals have a thickness of about 70 A. Thermoplastic Elastomers with a Polvfpivalolactone) Hard Segment Poly(pivalolactone) , poly(oxypivalyl) , is an excellent choice for a thermoplastic-elastomer hard segment due to its high tendency to crystallize, solvent resistance, and narrow molecular weight distribution. Caywood^^ modified a number of poly(alkyl acrylates) by saponifying some of the ester groups by reaction with tetrabutylammonium hydroxide and using the formed carboxylate salts to initiate polymerization of pivalolactone. Sharkey-^ ^'^'* synthesized block and graft copolymers of pivalolactone with isoprene and with isobutylene. Segmented poly (ester ethers) containing poly (pivalolactone) show promise as thermoplastic elastomers. Yamashita^-^ synthesized poly(pivalolactone-block-oxytetramethyleneblock -pivalo lactone) triblock copolymers by converting the potassium alkoxide anions of poly (oxytetramethylene) glycol to potassium carboxylate anions with succinic anhydride, followed by pivalolactone polymerization. Inoue and coworkers-^ ^ used aluminum porphyrin catalysts to synthesize low molecular weight versions of

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\I ' '-'' . . " . . "^ -'V " '•': .-.:_ ,. .. ^s .. , " ' ::<€-. ._.".' '_-s<-. . poly()3-propiolactone-block-oxyethylene) copolymers having monodisperse segments by sequential addition of ^S-propiolactone and ethylene oxide; however, this method is only useful for the synthesis of low molecular weight diblock copolymers. "' f'. /IfT^ T i .•' Wagener and Wanigatunga36-38 focused on the synthesis of a monodisperse telechelomer (a telechelomer is a selfreacting monomer capable of step polymerization only) and its step polymerization to segmented copolymer. Their approach (Figure 3), termed chain-propagation/ step-propagation polymerization, utilizes living anionic chain propagation to synthesize the narrow molecular weight distribution segments of the telechelomer sequentially. Then, step polymerization of the telechelomer results in a segmented copolymer, and although the overall molecular weight distribution will be large~Mv^/Mn greater than 2 — within each segmented copolymer the segments should maintain their narrow molecular weight distributions. Wagener and Wanigatunga^^"^^ utilized chain-propagation/step-propagation polymerization to synthesize poly(pivalolactone-block-oxyethylene) telechelomers (Figure 4). In the first step, an acetal capped anionic initiator (1) polymerized ethylene oxide to give 2, a potassium alkoxide of a masked poly (ether) . Excess succinic anhydride quantitatively converted the alkoxide anion of 2 to a carboxylate anion (3) , the preferred initiating anion for polymerizing pivalolactone smoothly. Then 3_ was used to polymerize

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10 \i-. .^^-^'^ nA i:(A)n" mB I-(A)n-(B)„,H3O* HO-I-(A)j,-(B)„-COOH step polym. -fO-I-(A)n-(B)^-CO]„Figure 3. Chain-Propagation/Step-Propagation Polymerization Strategy for Initiation by a Monofunctional Initiator. V t* -jV' J V ^-^,f s, ,^7i: • '-•• ':f;y-'r .

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:-i. jt. . _ ;-. ; _ ft*fc^"? •.3»«'• Figure 4. Synthesis of Poly(oxyethyleneblock-pivalolactone) Telechelomer (5) and Segmented Copolymer (6) . ;»-

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12 CH3-CH-0(CH2)30-K* OCH2CH2 1 "A CH3-CH-0(CH2)3-(OCH2CH-2)^0-K* , OCH2CH2 «^:. .°\!y° ; w .CH3-CH-0(CH2)3-(OCH2CH2)— COCH2CH2COO-K* OCH2CH2 .;y.':'-v CHa CH3^ m CH3 CH3-CH-0(CH2)3-(OCH2CH2)irSA-{OCH2-C-CO)^-OK* OCH2CH2 H,0* CH3 HO(CH2)3{OCH2CH2)— SA-(OCH2-C-CO)„-OH 5 ^*^3 1. 185°. alanine. 2 hrs. 2. 0.5 mm Hg. 0.5 hrs. 3. Ti(OBu)4. 185-260''C. At atmosphere. 1.5 hrs. 4. 0.5 mm Hg. 0.5 hrs. #. ri . » A >#i wv ' »« ' '••' CHa (CH2)3— (OCH2CH2)— SA-(0CH2-C-C0U-0-CH,

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' ' ' ' K ;;. 13 V-. J pivalolactone, giving a masked poly (pivalolactoneblock oxyethylene) copolymer salt (4) which was converted to telechelomer (5) by acid hydrolysis. Telechelomer 5 was converted to segmented copolymer (6) by melt esterification with alanine and titanium tetrabutoxide, where the role of alanine is unclear. Products 5 and 6 posses narrow molecular weight distributions for both segments, and depending on their ratio, the copolymers can act as thermoplastic elastomers wherein the poly{oxyethylene) segment acts as a soft phase and the poly (pivalolactone) segment acts as a hard phase. Wagener and Wanigatunga^O analyzed the microphase separation in telechelomer 5 and found that considerable microphase mixing occurs. V, ; , Objectives of This Dissertation In order to obtain a better understanding of the microphase separation of poly (oxyethyleneblock -pivalolactone) copolymers, the microphase separation behavior of poly (pivalolactone-block-oxyethylene-block-pivalolactone) oligomers is investigated as a function of the poly (pivalolactone) hard-segment length. The goal of this study is to determine the minimum length of hard segment necessary to achieve a high degree of microphase separation with a constant poly(oxyethylene) soft-segment length of 24 repeat units. .-•...:'•*

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•v>.^-a;,v 14 ;},-;: '"—.:<'.::. Previous poly (oxyethylene-block-pivalolactone) telechelomers^O exhibited considerable microphase mixing, and this microphase mixing can be attributed in part to the irregularity of the copolymer chain due to the initiator fragment and the succinate link. Therefore, a defect-free telechelomer should produce a segmented copolymer with superior microphase separation. The major goal of this work is the synthesis and characterization of a defect-free poly(oxyethylene-block-pivalolactone) telechelomer. After the telechelomers are synthesized, their step polymerization to segmented copolymers is addressed, including model studies utilizing homo-poly (pivalolactone) telechelomers.

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^^. :. EFFECT OF HARD-SEGMENT LENGTH ^V ^ ON MICROPHASE SEPARATION Introduction In a previous study aimed at gaining a better understanding of inicrophase separation, Wagener and Matayabas^l utilized DSC to quantitatively investigate the laicrophase separation behavior in a series of poly (pivalolactoneblock oxyethylene-block-pivalolactone) oligomers with the poly(oxyethylene) soft-segment length varying from 4 to 24 repeat units. The B-A-B triblock structure with two poly(pivalolactone) hard segments was chosen because it is the simplest segmented copolymer that can form a two-phase physical network in which the hard-phase domains are covalently linked by the soft segment. Their study showed that, with a poly(pivalolactone) hard-segment length of 12 repeat units, a minimum of 14 oxyethylene repeat units are required to achieve some degree of microphase separation and essentially complete microphase separation occurs when the poly (oxyethylene) soft-segment length is increased to 24 repeat units. In this present study the effect of hard-segment length on microphase separation is examined. The goal is to determine the minimum length of hard segment necessary to achieve a high degree of microphase separation with a constant poly(oxyethylene) soft-segment length of 24 repeat units.

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'^ '^ v.; J.-f ''' \ : " :" ''.^ :\ ^ Materials >:v,-';^ .:, -", 'v,^.^; Synthesis v'v. •''A series of poly(pivalolactoneblock -oxvethyleneblock pivalolactone) oligomers, represented by (PVL)iti-(OE) 24(PVL)jii, were synthesized according to the scheme presented in Figure 5. The poly (pivalolactone) hard-segment length (m) varies from 5 to 24 repeat units, and the poly(oxyethylene) soft-segment length was maintained constant at 24 repeat units by beginning with narrow molecular weight distribution poly (oxyethylene) glycol. ' ': -^ The hydroxyl end groups of the poly (oxyethylene) glycol were converted to carboxylic acid end groups in refluxing toluene with excess succinic anhydride, producing a-hydroxysuccinyl-w-hydroxysuccinyloxypoly (oxyethylene) (7) . Product 7 was converted to the dicarboxylate salt (8) by reaction with potassium metal in dry tetrahydrofuran under vacuum. Tetrahydrofuran solutions of 8 were used to polymerize pivalolactone under dry argon to produce the (PVL)jn-(OE)24(PVL)in oligomers. The length of the poly (pivalolactone) hard-segment block (m) is easily controlled by the stoichiometric ratio of initiator to monomer due to the anionic ring-opening polymerization mechanism, and (PVL)jn-(OE)24(PVL)ji, with m = 5, 7, 9, 12, 16, and 24 were synthesized. Due to the solvent resistance of the poly (pivalolactone) segments, the (PVL)i[i-(OE) 24-(PVL)in oligomers with m greater than 7 are insoluble in most organic solvents including acetone, methylene chloride, chloroform.

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"^.,17 . _.-/.; acetonitrile, dimethylsulf oxide, and cold N,N-dimethylformamide. They are soluble in acidic solvents such as 3methylphenol , 4-chlorophenol, and methylene chloride with 1% trifluoroacetic acid. The (PVL)i„-(OE)24-(PVL)in oligomers are soluble in hot N,N-dimethylformamide and precipitate only slowly on cooling. , / . Determination of Molecular Weight ".. ,. -^ The molecular weight of the poly (oxy ethylene) macromolecular initiator, 7, was determined by titration with 0.10 N potassium hydroxide in methanol, giving a numberaverage molecular weight (M^) of 1260 g/mole. This value agreed well with the proton NMR integration of the poly(oxyethylene) methylene singlet and the succinate methylene singlet. The existence of a narrow molecular weight distribution — M^/M^ less than 1.05 — was confirmed by sizeexclusion chromatography. '-v The proton NMR of (PVL) i2-(0E) 24-(PVL) ^2/ in Silanor-C with 1% trifluoroacetic acid, is presented as Figure 6. The average value of m is easily determined by detecting and integrating the proton NMR signals of the 1.23 ppm methyl singlet (a) of the main chain poly(pivalolactone) segment and the 1.31 ppm methyl singlet of the terminal pivalolactone unit. Additional information regarding the amount of incorporated pivalolactone is obtained from comparison of the poly(oxyethylene) methylene singlet (c) at 3.72 ppm, the poly (pivalolactone) methylene singlet (d) at 4.12 ppm, and the succinate link methylene singlet (b) at 2.69 ppm.

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.^i.-. !#:• H-(OCH2CH2)24-OH ,»Yr° 2. work up o o ,^ , * o o II 11 t 1.J iT V HOC-CH2CH2-C— (OCH2CH2)24-OC-CH2CH2-COH K. THF ^ , o o o o *KOC-CH2CH2-C-(OCH2CH2)24-OC-CH2CH2-COK* 8 CH3^.A /^ 2m O CH, II I "* H3C o ' II *K-0-(C-C CH20)n-SA-(OCH2CH2)24SA-(OCH2-C-C)n— OK* CH3 HoC (PVL)^-(OE)24-(PVL), 'm Figure 5. Reaction Scheme for the Synthesis of Poly(pivalolactone-block-oxvethvleneblock -pivalolactone) Triblock Oligomers. :.",>••;*''_v--:^ '/ . : ..-^i^':. i.: .*• .i r

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19 '/:-': 9 ?"' 9 9 -9 9 CH, o »K-0.(C-C-CHjO),j-C.CHjCH,-C-(OCHjCH,)„0-C-CHjCH,-C-(OCH,.C-C),,.OKc/e^ "'-?»». ''rlf''""''' /*"•',, *; ?''-'. *«*>.. j ii. , V.-* ,: : ,J'' I* ja«» b A. ' ' ' ' ' ' ' ' ' ' I ' I . I , , , , , I , , , * .. .. 3: ... i ppm i Figure 6. Proton NMR of (PVL) i2-(OE)24-(PVL) i2'

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20 Determination of Intrinsic Viscosity Recently, Guillet^^''*^ showed that excellent agreement of the intrinsic viscosity ([n]) is obtained from a single measurement of the viscosity of polymers in the molecular weight range 10-^-10^ using the Solomon-Ciuta equation'*^: [n] = [2 ngp 2 ln(nr)]^/2/c (1) where ngp represents the specific viscosity, n^. represents the relative viscosity, and c represents the concentration of the polymer solution. Table 1 presents the number-average molecular weights, Mfj, determined by proton NMR and the measured intrinsic viscosities, [n], of 0.005 g/ml solutions of the (PVL)jn(OE)24-(PVL)j^ oligomers in methylene chloride containing 1% trifluoroacetic acid at 30 "C, calculated by Equation 1. Table 1. Intrinsic Viscosities ([n]) and Number-Average Molecular Weights (M^) of (PVL)m-(OE)24-(PVL)„i Oligomers. m 5 7 9 12 16 24 Mn 2400 2900 3100 3900 4500 6100 [n] dl/g 0.075 0.081 0.083 0.084 0.098 0.104 Determination of Mark-Houwink Parameters For linear polymers, a plot of ln[n] versus InM^ produces slope = a and intercept = InK, according to the Mark-Houwink Equation'*^: ln[n] tt'lnMy + InK (2)

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21 where K and a are termed the Mark-Houwink parameters, and My represents the viscosity-average molecular weight. Dondos et al.'^^, showed that this relationship also holds for linear block and random copolymers. The error resulting from substituting M^ for M^ is small for narrow molecular weight distribution samples, '*2 and from the plot of Equation 2 for the (PVL)iu-(OE)24-(PVL)jn oligomers (Figure 7) , a = 0.35 and K = 0.48 ml/g. Size-exclusion Chromatography The validity of the calculated Mark-Houwink parameters for the (PVL)j[i-(OE)24-(PVL)m oligomers was checked by sizeexclusion chromatography (SEC) analysis versus poly(styrene) standards — see EXPERIMENTAL for the determination of the Mark-Houwink parameters for poly(styrene) . The samples were analyzed at concentrations of 0.005 g/ml in methylene chloride containing 1% trif luoroacetic acid. Under these conditions, the (PVL)j^-(OE)n-(PVL)jjj oligomers gave only weak signals as detected by a differential refractometer. Homopolymers of pivalolactone and ethylene oxide give signals with opposite polarities in this solvent, and the copolymer signals are weak due to the opposing polarities of the poly (pivalolactone) and poly (oxyethylene) signals. The weak signals were partially masked by the solvent signal, and this prevented obtaining reliable polydispersity data. However, the peak molecular weights, which should correspond well with Mn for narrow molecular weight distribution polymers, agreed well with the known composition.

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22 £. 2.2 Figure 7. Plot of Mark-Houwink Equation (Equation 2) for (PVL)j^-(OE) 24-(PVL)jn oligomers.

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23 Viscosity Measurements in Other Solvents Attempts to determine the intrinsic viscosity of the (PVL)j„-(OE)24-(PVL)iii oligomers in N,N-dimethylformamide were met with many difficulties due to formation of aggregates and slow precipitation of the solute. For example, the intrinsic viscosity of (PVL)9-(OE)24-(PVL)9 was determined to be 24.5 ml/g within two hours of dissolving in hot N,Ndimethylformamide and increased to 28.7 ml/g 24 hours later. Plots of Equation 2 for (PVL)iii-(OE) 24-(PVL)iii in N,N-dimethylformamide produced a = 3.0 and K = 0.12 ml/g. Analvsis of Microphase Separation DSC is an excellent method of detecting glass transitions and melting points. ^^ For a polymer containing an amorphous soft phase and a crystalline hard phase, DSC evaluation of microphase separation is accomplished by l) comparing the observed glass transition temperature of the soft phase (Tg°^S) of the segmented copolymer with the glass transition of the soft-segment homopolymer (Tg^) and 2) comparing the observed melting point temperature of the hard phase (Tjn^'^^) with the melting point of the hard-segment homopolymer (Tjn") . The strength of this process lies in its ability to produce a complete description of the microphase separation behavior, providing information about the soft and hard phases. V •« vv

PAGE 31

24 100 -50 Temperature (^'C) 50 Figure 8. Low Temperature DSC Scans of (PVL)n,-(OE)24-(PVL)ni Quenched from 50°C.

PAGE 32

25 Analysis of the Soft Phase The low temperature DSC scans of (PVL)jn-(OE) 24-(PVL)jj, triblock oligomers, with soft-phase glass transitions normalized per gram of sample, are presented in Figure 8. Each sample was quenched from 50 °C in order to freeze the soft phase into a fully amorphous state at Tg°^^ and to guarantee that the thermal history of each sample is identical. The recorded values for Tg°^s and change in heat capacity per gram of soft segment (deltaCp^^^/Wg) of (PVL)jji(OE)24-(PVL)j„, reported in Table 2, show a distinct difference in the glass behavior of the soft phase in the samples with m greater than 9. The samples for m = 5, 7, and 9 exhibit Tg°^s between -46 and -^l^C, and the samples for m = 12 and 16 exhibit TgObs at -60 and -61*C, respectively, indicating a marked increase in the soft-phase purity in these samples. An analysis of the soft-phase microphase separation of m = 24 is presented; however, Tg°^^ for m = 24 is difficult to determine due to the small weight percent of soft phase in this sample. Factors known to affect Tg°^^ include molecular weight, end groups, percent crystallinity, thermal history, and diluents.** Thus, with all other factors being equal, an increase in Tg°^^ is an indication of the presence of a diluent.

PAGE 33

26 Wood^S demonstrated that the observed glass transition temperature of a single-phase, two-component system is the linear weighted addition of the two individual glass transitions: (k-Wi + W2)TgOJ3S = k-Wi-Tgl + W2-Tg2 (3) where W^ and W2 represent the weight fractions of components 1 and 2, and Tg^ and Tg2 represent the glass transition temperatures of components 1 and 2, and k is a constant. Several researchers'* 6-49 ^ave attempted to assign physical significance to the constant, k, while Wood supports determining k by studying samples of known composition and plotting the results according to the following rearranged form of Equation 3: TgOJ^S = (.l/k) (TgObS _ Tgl) (W1/W2) + Tg2 (4) A plot of TgOl^s versus (TgO^s _ Tg^) (W1/W2) produces a line having slope = -l/k and intercept = Tg2. Wood's equation has been shown to apply to microphase separated segmented copolymers having a mostly crystalline hard phase that is rich in component 2 (called the hard segment) and a mostly amorphous soft phase that is rich in component 1 (called the soft segment) .3-5,21 Because this is a two-component, two-phase system in which only the amorphous soft phase participates in the glass transition, the individual weight fractions W^ and W2 in Equation 3 become the weight fractions of the soft and hard segments in the soft phase, Mgs and Mjjs respectively: (k-Mss + MHs)TgO^S = k-Mss-TgS + Mng'TgH (5)

PAGE 34

,,.; ....^ -;;. ^ 27 ";*",--'" ~ '" Where Tg^ and Tg^ represent the glass transition temperatures of the ideally microphase separated soft and hard segments, respectively. ^ . Solving Equation 5 for Mss produces Equation 6: Mss = (k-TgH y.'Tg°^^) / (Tg°^^ Tg^ + k • Tg" " k • TgO^^S ) (6) From Equation 6, and noting that Mhs = Mss ~ ^' the softphase composition is determined from the observed glass transition temperature of the amorphous phase, provided that suitable values for k, Tg^, and Tg^ are found. Table 2. Results of Quantitative DSC Analysis of the Soft-Phase Microphase Separation of (PVL)j„-(OE)24-(PVL)in Oligomers. m 5 7 9 12 16 24 Ws 0.50 0.45 0.38 0.29 0.25 0.18 TgObs oc -46 -44 -42 -60 -62 -52 deltaCpOl^S/;^ 0.76 0.74 0.65 0.79 0.81 0.4 "SS ^; 0.46 0.43 0.39 0.98 1.1 0.6 SRs ^ -i.' -— 0.95 0.98 0.5 The values of Mss» reported in Table 2, were calculated according to Equation 6, using k = 0.24, Tg^ = T>C, and T„^ = -eo^C, as determined in the previous study. 21 The values of Mss clearly show that substantial microphase mixing occurs for the samples for m = 5, 7, and 9. The observance of a cold crystallization for (PVL) 5-(0E) 24-(PVL) 5 indicates

PAGE 35

28 that microphase separation has occurred; however, the value of 0.46 for Mss indicates that no microphase separation has occurred. Perhaps a value of 0.24 for k, determined for triblocks containing 12 poly(pivalolactone) repeat units, is inaccurate for this sample. Based on the calculated values of Mgs/ the soft phase in the samples for m = 12 and 16 are nearly pure in soft segment, and the value of 0.98 for Mss °f (PVL) i2~(0E) 24" (PVL) 12 indicates that the soft phase contains 98% by weight poly(oxyethylene) soft segment. The observance of a cold crystallization and the melting of the crystalline regions in the soft phase of (PVL) i6-(OE)24-(PVL) ^g clearly indicate high soft-segment purity, and a value of l.l was calculated for Mss* A value greater than unity for Mss reveals the limitations of estimating Tg^, the glass transition temperature of the ideally microphase separated soft segment, with the glass transition temperature of the poly(oxyethylene) initiator 7. Soft-Segment Segregation Camberlin and Pascault^'"7 introduced a method of determining the soft-segment segregation (SRs) , which is defined as the weight fraction of soft segment in the soft phase with respect to the total weight of soft segment in the copolymer: SRs = (deltaCpObs/Wg)/deltaCpS (7) where deltaCp°^s/Wg represents the observed change in heat capacity per gram of soft segment in the copolymer, and

PAGE 36

29 S deltaCpS represents the change in heat capacity at the glass transition of the soft-segment homopolymer. Camber lin and Pascault^''^ used Equation 7 to quantitatively determine the soft segment segregation of segmented copolymers containing diphenylmethane diisocyanate based poly(urethane) and poly (urea) hard segments and varying soft segments. Brunette et al.,^ used a similar equation to quantitatively determine the soft phase composition of segmented copolymers containing diphenylmethane diisocyanate based poly(urethane) hard segments and poly(oxybutadiene) soft segments. Equation 7 does not take into account the contribution to deltaCp°^s by the hard segments in the soft phase, and Wagener and Matayabas^O showed that when this contribution is considered, a slightly different equation results: SRg = (Mss-deltaCpObs/Wg)/(Mss-deltaCpS + Mns-deltaCpH) ( 8 ) where deltaCp^ represents the change in heat capacity at the glass transition of the hard-segment homopolymer. If the multiphase copolymers are very well microphase separated or if deltaCp^ is very small, then Equation 8 reduces to Equation 7, and since the change in heat capacity for poly(pivalolactone) is too small to be detected by DSC, Equation 7 is valid for microphase separated poly(pivalolactone-blgck-oxyethylene) copolymers. The values of SRg, also in Table 2, were calculated according to Equation 7, where deltaCp^ = 0.83 as previously determined . 2 1 a value of 0.95 for (PVL) i2-(0E) 24-(PVL) ^2

PAGE 37

30 indicates that 95% of the poly(oxyethylene) soft segments in this sample is located in the soft phase, leaving 5% in the hard phase or a mixed interface. And a value of 0.98 for (PVL)i5-(OE)24-(PVL)i6 indicates that essentially all of the soft segments are located in the soft phase. Determination of the Hard-Phase Composition Once both Mgg and SRg are known, it is a simple matter to determine the composition of the hard phase. Assuming that only two phases are formed, the weight fraction of the hard segment in the hard phase (Mfijj) can be estimated^!: Mhh = 1 [Mss-Ws(l SRs)/(Mss " SRg-Wg)] (9) And, similar to SRg, the hard-segment segregation (SRjj) is calculated by the following equation^^: SRh = (Mss'Mhh SRs-Ws-Mhh)/(Mss-Wh) (10) where Wy represents the weight fraction of the hard segment in the copolymer (Wjj = 1 Wg) . The calculated values of Mjjjj and SRjj, listed in Table 3, indicate high hard-segment purity in all of the microphase separated samples. A 0.99 value of Mjjjj for (PVL) 12" (OE)24-(PVL) 12 indicates that the hard segment of this sample contains 99% by weight poly(pivalolactone) hard segment, and a 1.0 value of SRjj for (PVL) i6-(OE)24-(PVL) 15 indicates complete microphase separation. Figure 9 presents the high temperature DSC scans of (PVL) jn-(OE) 24-(PVL) jn/ showing the hard-phase melting endotherms (Tj^°^^) . The values of 1^°^^, listed in Table 3, increase with increasing hard segment length m.

PAGE 38

31 '»^ri<-; ; 'l-'-^:' Temperature ("C) 2S0 Figure 9. High Temperature DSC Scans of (PVL)i„-(OE)24-(PVL)m Oligomers. itf.'^ s «.»•

PAGE 39

"-vr" .": ' 32 Table 3. Results of Quantitative DSC Analysis of the Hard-Phase Microphase Separation of (PVL)ji-(OE)24-(PVL)j„ Oligomers. m %H SRh m obs or* ••la *rp H o p 5 7 9 12 16 24 0.50 0.55 0.62 0.71 0.75 0.82 — ., ^: — — 0.98 0.99 0.9 — . «»•» '0.99 1.0 0.9 142 152 172 200 201 207 174 182 190 201 205 215 0.73 0.76 0.76 0.99 0.94 0.94 Block copolymerization decreases the observed melting point (Tj^°^^) of a crystalline segment, and Tjn°^^ in a block copolymer can be calculated by Equation 11^2. l/T^obs = 1/Tjtt" (R/deltaH) -InpH •; -i^ V (11) where Tj^^^ represents the melting point of the hard-segment crystalline homopolymer, deltaH represents the heat of fusion per mole of repeat unit of the crystalline hardsegment, and p^ represents the hard-segment crystalline sequence propagation probability. This equation has been used to calculate Tjj°^^ of the poly(hexamethylene sebacate) segment due to block copolymerization with a poly (dimethyl siloxane) segment. ^-^'^^ Wagener and Wanigatunga^O used Equation 11 to calculate the upper and lower limits of the poly(pivalolactone) hard segment in their poly (oxyethyleneblock-pivalolactone) telechelomers. The upper limit, with p^ = 1, equals Tm^, and the lower limit was calculated using

PAGE 40

33 p^ = Wjj. The lower limit is the Tin°^^ expected if no microphase separation occurs, and the upper limit is the Tjii°^^ expected for complete microphase separation. From this range, they were able to qualitatively determine the hard phase composition. An interesting application of Equation 11 is obtained by solving for p^: pH = EXP[(l/Tro" l/TjnObS) .deltaH/R] (12) From Equation 12, p^ can be calculated, and p^ should be a very good approximation for SRfj. The values of p^ for the (PVL)in-(OE)24-(PVL)j„ oligomers in Table 3, were calculated from Equation 12 using a value of 3550 cal/mole of repeat unites for deltaH and the 1^^ of homopoly(pivalolactone) with the corresponding molecular weight, also listed in Table 3. The calculated values of p^ show that the crystalline hard-phase purity increases with increasing hard-segment length for m = 5 through 12. The values between 0.73 and 0.86 for m = 5, 7, and 9, in contrast to the soft segment data, indicate that the hard segment has partially microphase separated. For example, the 0.73 value of p^ suggests that the crystalline hard phase of (PVL) 5-(0E) 24-(PVL) 5 is richer in poly(pivalolactone) hard segment than the 0.50 value, from Wjj, that is expected if no microphase separation occurs. The 0.99 value of p^ for m = 12 is identical to the SRji calculated from the soft-segment data and indicates that the crystalline hard phase of (PVL) 12" (OE) 24(PVL) 12 is

PAGE 41

34 completely itiicrophase separated. The 0.94 value of p^ for m = 16 also indicates a high degree of crystalline hard-phase purity; however, this value is slightly lower than the 1.0 value of SRjj. The 0.94 value of p^ for m = 24 agrees well with the 0.9 value of SRjj. Chapter Summary Quantitative determination of the microphase separation in a series of (PVL)jii-(OE) 24-(PVL)jn oligomers was achieved by DSC analysis. The poly(oxyethylene) soft-segment length was maintained at 24 repeat units, and the poly(pivalolactone) hard-segment length (m) was varied from 5 to 24 repeat units. For shorter hard-segment lengths, the soft phase is microphase mixed; however, the crystalline hard phase appears to exhibit a small degree of microphase separation. A very distinct transition from microphase mixed to essentially complete microphase separation occurs when m is increased from 9 to 12. Complete microphase separation occurs for (PVL) i6-(0E) 24-(PVL) ^gm each case, the hard-segment is the major component, and microphase separation occurs to a larger extent in the hard phase than in the soft phase.

PAGE 42

f f""' SYNTHESIS OF DEFECT-FREE TELECHELOMERS Introduction Poly foxvethvleneblock -pivalo lactone) segmented copolymers have promise as thermoplastic elastomers; however, the low melting points of the existing telechelomers^O indicate that substantial microphase mixing occurs. The initiator fragment and the succinate link comprise over 6% of the total weight of the telechelomer and are probably responsible for much of the microphase mixing. If this is the case, a telechelomer that is free from these defects should exhibit excellent microphase separation. Siloxv-Protected Initiator It is possible to eliminate, or mask, the initiator fragment in the synthesis of poly (oxvethvleneblock -pivalolactone) telechelomers by duplicating the chain-propagation/step-propagation strategy utilizing initiators that leave a fragment that has the same structure as the polymer repeat unit. Polymerization of ethylene oxide with a monoprotected ethylene glycol initiator would result in a poly(oxyethylene) in which the initiator fragment has a structure identical to the poly(oxyethylene) repeat unit. The trimethylsiloxy protecting group has been shown to be fairly stable in the anionic polymerization of 2-(trimethylsilyloxy) ethyl methacrylate at -78 °C with some anionic 35

PAGE 43

36 initiators^fi, and 2(dimethylthexylsiloxy) ethanol was selected to attempt polymerization of ethylene oxide. Synthesis 2(dimethylthexylsiloxy) ethanol (11) was synthesized by the reaction scheme presented in Figure 10. The reaction of dimethylthexylsilyl chloride with 2-benzoxyethanol, in N,Ndimethylformamide in the presence of imidazole, produced 1benzoxy-2(dimethylthexylsiloxy) ethane (10), isolated by vacuum distillation. Hydrogenation of 10 with H2 and palladium-charcoal in dry tetrahydrofuran produced 11 in 98% purity, by gas chromatography, after vacuum distillation. The proton NMR of 11 (Figure 11) , in deuterated chloroform without tetramethylsilane, has three characteristic methyl signals: the dimethyl singlet at 0.0 ppm (a, 6 hydrogens) and the thexyl group methyl singlet (b, 6 hydrogens) at 0.75 ppm and methyl doublet (c, 6 hydrogens) at 0.8 ppm. The other signals are the tertiary-hydrogen multiplet (d) centered at 1.51 ppm, the alcohol proton singlet (e) at 2.04 ppm, and the glycol methylenes pair of multiplets (f, 4 hydrogens) centered at 3.55 ppm. Polvmerization ^ Figure 12 presents the reactions obtained by the polymerization of ethylene oxide with 11. The potassium salt of 11 (12) was formed by reaction with potassium mirror in tetrahydrofuran, with precipitation of the product. Ethylene oxide was vacuum transferred into the reaction flask in a 20:1 ratio, and the reaction was stirred

PAGE 44

37 at 5»C for 3 days. The polymer product (13) was isolated by evaporating the tetrahydrofuran, dissolving the residue in water, acidifying with dilute hydrochloric acid, and extracting with methylene chloride. Product 13 was determined to be poly(oxyethylene) glycol by proton NMR, with M^ = 2100 and M^^/Mn = 1.1 by SEC, calibrated with poly(oxyethylene) glycol standards. To determine whether or not the siloxane was hydrolyzed, later polymerizations were quenched after 2 days with succinic anhydride, without hydrolysis of the final product (14) • The SEC trace of 14 produced one slightly broad signal, with M^ = 1800 g/mole. The composition of 14. was determined by proton NMR (Figure 13) integration of the 12hydrogen methyl singlet and doublet of the siloxy group at 0.8 ppm (a), the 4-hydrogen methylene singlet of the succinate group at 2.55 ppm (b) , and the methylene singlet of poly(oxyethylene) at 3.55 ppm (c) . The other signals result from the methylene at the end of the poly (oxy ethylene) chain that is linked with the succinate group (d, 4.2 ppm triplet) and the methyls attached to silicon (e, ppm singlet). Product 14 is a 4:1 mixture of the diand monosuccinate poly (ether), a-hydroxysuccinyl-w-hydroxysuccinyloxypoly(oxyethylene) and a -hydroxy succinyl-w-( dimethyl thexylsilyloxy)poly(oxyethylene) , respectively. Precipitation of concentrated methylene chloride solutions of mixture 14 with diethyl ether resulted in the isolation of a white solid containing very little siloxane.

PAGE 45

38 > •Si-Cl + HO-CHaCHa-O-CHg-^ imidazole, DMF Si-O— CH2CH2— aCHj IQ. H2. Pd/C Si-OCH2CH2~OH n Figure 10. Reaction Scheme for the Synthesis of 2-(Dimethylthexylsiloxy)ethanol, 11 . ''A,.;/

PAGE 46

39 CHo CHq CHo H-C — C Si-OCHoCHo-OH III ^ ^ . CH3 CH3 CH3 c b a ^tfi. t. * '^'^ Jk t! d -A. julll. I 3 .2 1 ' Oppm Figure 11. Proton NMR of 2-(Dimethylthexylsiloxy)ethanol, 11.

PAGE 47

AQ > > Si-OCHoCHo— OH I K.THF Sl-OCHoCH,— OK* I H-(OCH2CH2)n-OH 4 HOaCCHaCHaCO-COCHaCHzJn-OaCCHzCHaCOaH IS I 1 HO2CCH2CH2CO— (OCH2CH2)n-0-Sl^^^•^ --^^-rrK 11 Figure 12. Reactions Obtained From the Polymerization of Ethylene Oxide by 2-(Dimethylthexylsiloxy)ethanol, 11. 'n:,:-i-'^' •^"''f'

PAGE 48

41 HO2CCH2CH2CO— (OCHjCHalnO2CCH2CH2CO2H V V V ,. b c.d b K h HO2CCH2CH2CO— (OCH2CH2)naS iV e a a 4A. " W. . jii ' ' ' I ' ' ' I I ' ' ' ' I ' ' ' ' I ' ' I I I ' ' ' ' I ' ' ' ' I ' I I I I I P I I I I r4 3 2 1 Oppm Figure 13. Proton NMR of H. V'' ' < . rW'V

PAGE 49

42 • The siloxy protecting group is not stable under the harsh conditions of the anionic polymerizations at S^C, and this is not a viable route to poly(oxyethylene-block-pivalolactone) telechelomers. It may prove to be a route to high molecular weight poly (oxy ethylene) glycols with fairly narrow molecular weight distributions; however, this avenue was not pursued. Hydroxy Acid Initiators Introduction The formation of a diblock species from ethylene oxide and pivalolactone without the use of succinic anhydride to convert the alkoxide to a carboxylate requires that the carboxylic acid and hydroxyl functionalities be already present in the initiator. Initiation by a hydroxy acid, a difunctional initiator, to form a diblock telechelomer requires polymerization from both ends of the initiator in an inside out fashion much like that used to form the triblock structures. This chain-propagation/ step-propagation polymerization strategy for initiation by a difunctional initiator, presented in Figure 14, is a novel utilization of a difunctional initiator. is. Since hydroxy acids are difunctional initiators, it may be possible to achieve the simultaneous polymerization of pivalolactone and ethylene oxide, referred to as dualanionic polymerization, provided that selectivity is achieved on the bases of nucleophilicity. Alternatively, sequential addition of ethylene oxide and pivalolactone

PAGE 50

43 should yield the desired telechelomer. First polymerizing pivalolactone is unlikely to succeed because poly(pivalolactone) is insoluble in tetrahydrofuran and decomposes when reacted with a potassium mirror. Initial Attempts Two hydroxy acids were used in the initial attempts to synthesize poly (oxyethylene-block-pivalolactone) telechelomers: 4-hydroxybenzoic acid and glycolic acid. Unfortunately, the carboxylate salt of 4-hydroxybenzoic acid was found to be a poor initiator for pivalolactone, resulting in long reaction times and broad molecular weight distributions. Hall26 investigated the rate of initiation and polymerization of pivalolactone with tetramethylammonium benzoate, and he found that the rate of initiation is 270% slower than the rate of propagation. In addition, initiation with tetramethylammonium benzoate occurred 750% slower and polymerization occurred 170% slower than initiation and polymerization with tetraethylammonium pivalate under similar conditions. After conversion of 4-hydroxybenzoic acid to the dipotassium salt by reaction with potassium mirror in tetrahydrofuran, with precipitation of the product, attempts to polymerize ethylene oxide were unsuccessful due to a combination of the low nucleophilicity of the phenoxide anion and the inhomogeneous conditions.

PAGE 51

%A nA '•<'.• "I* "r ' >-l '(A)n-I* mB (A)„-I-(B)^ HaO"HO-(A)„-I-(B)„,-COOH step pol5mi. y*r^T i* i« .4* .1-*.. «•'*-•# *f* . -[0-(A)„-I-(B)^-COLIfI = B -[0-(A)„-(B)^^i-COLFigure 14. Chain-Propagation/Step-Propagation Polymerization Strategy for Initiation by a Difunctional Initiator.

PAGE 52

Glycol ic acid is a very hygroscopic, viscous liquid that is difficult to dry completely, and formation of the dianion, which precipitates from solution, requires several days of reaction with a potassium mirror. Attempted dual anionic polymerization with glycolic acid produced materials with very little oxyethylene content in about 10% yield. Attempts to isolate the poly (oxyethylene) segment by selectively hydrolyzing the unhindered ester with dilute hydrochloric acid were unsuccessful. The resulting material showed only a decrease in poly (oxyethylene) content. Synthesis of Defect-Free Telechelomers One can draw the structure of the defect-free telechelomer (Figure 15), represented by (OE)n-(PVL)jiiInitiation by hydroxypivalic acid could result in defect-free telechelomer, (OE)n-(PVL)ju/ since 1) the initiator fragment is identical to the poly (pivalolactone) segment repeat unit and 2) both the hydroxyl and carboxylic acid functionalities are already present. ; . Formation of Dianionic Initiator Hydroxypivalic acid is a sublimable white solid that is easily dried with a modified Abderhalden drying pistol^^ and handled using high vacuum line techniques. To initiate polymerization of ethylene oxide, hydroxypivalic acid must first be converted to the dipotassium salt by reaction with potassium mirror in tetrahydrofuran (Figure 16) . The acidic proton reacts very quickly to form the hydroxycarboxylate salt (15), which precipitates. The

PAGE 53

46 formation of the dipotassium salt (16) requires several days and periodic degassing. To verify that the dipotassium salt is formed, three reactions of hydroxypivalic acid in tetrahydrofuran with an excess of potassium mirror under vacuum were terminated after 24, 48, and 72 hours, with degassing every 24 hours. Back-titrating the products with hydrochloric acid, using phenolphthalein indicator, provided an estimation of the extent of reaction. The difficulty of completely removing the precipitated product from the potassium mirror made this process qualitative at best; however, the information obtained by titration was verified by proton NMR detection and integration of the hydroxyl proton signal at 4.5 ppm of dilute solutions of the products in Silanor-C. After 24 hours only about 20% of the hydroxyl protons reacted, after 48 hours about 80% had reacted, and after 72 hours essentially complete formation of dianion 16 occurred. To improve the solubility of the product and the reactivity of hydroxypivalic acid, 18-crown-6 was added in a 1:1 molar ratio. The addition of 18-crown-6 in tetrahydrofuran to a potassium mirror under vacuum formed a dark blue solution. Subsequent addition of hydroxypivalic acid in tetrahydrofuran resulted in a violent initial reaction with the immediate loss of the blue color. The formation of the dianion was shortened to two days, after which the blue coloration began to reform; however, substantial precipitation still occurred. l ; V

PAGE 54

47 CHo H-(OCH2CH2)n— (OCH2-C-CO)^-OH ^3 CH. (OE)n-(PVL) m Figure 15. Structure of Defect-Free Poly (pivalolactone-block-oxyethylene) Telechelomer .

PAGE 55

48 CH3 HOCH2-C-COOH CH. K. THF t CH. I HOCH2-C-COO-K* I CH. 15 K. THF t CH< "KOCHg— c— COOK"^ CH. 16 Figure 16. Formation of the Dipotassium Salt of Hydroxypivalic Acid.

PAGE 56

/V['\ --c^; ' 49 Increasing the ratio of 18-crown-6 to hydroxypivalic acid to a 2:1 molar ratio resulted in the formation of a viscous gel that could not be stirred with magnetic stirring. Under high shear, such as shaking or mechanical stirring, the gel became less fluid and precipitation occurred. The precipitant was isolated by filtration, neutralization with water and then dilute hydrochloric acid, extraction with methylene chloride, and evaporation of the methylene chloride, resulting in recovery of the hydroxypivalic acid starting material. Thus, the gel formation is probably due to the formation of aggregates. Attempts to prevent precipitation of the dianion by using of larger amounts of tetrahydrofuran and by using N,N,N' ,N'-tetramethylethylenediamine as a solvent were not successful. , . Dual Anionic Polymerization T:; . Although the dual-anioijic polymerization approach (Figure 17) is interesting, there are many undesired reactions that can occur. In practice, only a limited amount of ethylene oxide is incorporated into the product, indicating that the alkoxide anion is reacting with pivalolactone in such a way as to prevent reaction with ethylene oxide. One likely possibility is attack at the methylene carbon of the lactone by the alkoxide anion (Figure 18) , thereby converting the alkoxide anion into a carboxylate anion and making further reaction with ethylene oxide impossible.

PAGE 57

-"fPt'f.W? ^" -'.^•^fT'v^" 'it: S^it ': -^CH3 ^KOCHa-c-COOK-^ I CH. m K.--^i; .-,' nrtttfOfr*,!* 1 U\.f>, " I H-(OCH2CH2)n,-(OCH2-C-CO)n-OH CH. Figure 17. Reaction Scheme for the Dual-Anionic Polymerization of Ethylene Oxide and Pivalolactone.

PAGE 58

o II o-c ~*'^'^'*''^'*''*'*^ CHo — O' j^y,. o II o-c /N/WWW>/WVW\ CH2O— CH2C(CH3)2C— O" *-
PAGE 59

52 Sequential Addition Polymerization Figure 19 presents the sequential addition polymerization reaction scheme used to produce defect-free telechelomers (OE)n-(PVL)Bj. Ethylene oxide is vacuum transferred into a solution of 16 in tetrahydrofuran, and the reaction mixture is stirred at 5°C for several days. The product, a-hydro-w(hydroxypivalyloxy) poly (oxyethylene) (17) , is isolated by evaporation of the tetrahydrofuran, dissolving the residue in water, acidifying with dilute hydrochloric acid, extracting with methylene chloride, and precipitating the product in diethyl ether. Deprotonation of the acid proton produces the potassium carboxylate (i8) , which is used to polymerize pivalolactone in tetrahydrofuran, under argon. The tetrahydrofuran is evaporated under reduced pressure and methylene chloride is added to dissolve as much of the residue as possible. The resulting solution is shaken with dilute hydrochloric acid and separated. The defect-free telechelomer, (OE)n-(PVL)jn, is isolated by precipitation in diethyl ether or by evaporation of the methylene chloride. Control of the Soft-Secment Length The proton NMR of (OE)34-PVL (17) (Figure 20) is very simple, having three large singlets at 3.7, 4.6, and 1.2 ppm, resulting from the poly (oxyethylene) methylene protons (a) , the pivalic acid end-group methylene protons (b) , and the pivalic acid methyl protons (c) , respectively. The poly (oxyethylene) segment length (n) is easily determined by

PAGE 60

. " •';-. ,_,. 53 proton NMR integration and verified by titration of the acid end group and SEC. ' The polymerization of ethylene oxide to form 17 was conducted at various conditions, and the percent yield, number-average molecular weight determined by titration, and the SEC molecular weight distribution of each product, 17 . is listed in Table 4. Due to the inhomogeneous initiator, the products in Table 4 all have molecular weights higher than that predicted by the stoichiometric ratio (Mj^ Obs) ; however, some control of n is obtained by varying the conditions. In a typical experiment, the ratio of monomer to initiator was 1 to 20, the ethylene oxide polymerization was given a static argon atmosphere that was open to a mineral oil bubbler to allow the release of sudden pressure, and the reaction temperature was maintained at 5">C for a specific number of days in order to keep the volatile ethylene oxide in the reaction solution. In the first polymerization, the reaction was stirred at 5°C for one day, allowed to warm to room temperature and stirred for two additional days. The yield was slightly diminished and the polydispersity was very much improved by the precipitation of the product from diethyl ether, removing any low molecular weight polymer. The resulting product had M^ = 3780, 280% larger than that predicted by the initiator to monomer ratio. This difference is most likely due to the inhomogeneous nature of the dianionic initiator. ''';'";' . ' '' '% ' "V-. ,

PAGE 61

54 •' ---• .^-'y # CH3 *K-OCH2~C-COO-K* CHo 23 O 1. m/ \ .THF 2. H3O* -' '' CHq 1 ^ H-(OCH2CH2)i„--OCH2— C-COOH 12 CH3 ;y KOH. MeOH CH3 . H-(OCH2CH2)ni-OCH2-— C-COOK* I CH. CH3 2 t . f: u^ 1n-l| ^ ,THF 2. H3O* CH3 H-(OCH2CH2)m-(OCH2-C-CO)„-OH I CH. ; ^<,^. (OE)„-(PVL) m Figure 19. Reaction scheme for the Synthesis of Defect-Free Telechelomers by Sequential Chain-Propagation Polymerization.

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•^^^^^'rPT • • TT" '^V'" m H-(OCH2CH2)34 *^ *«v .;-.'^'.^\.'*;> J ' ' I ' ' ' ' I ' ' ' ' I ' ' ' ' 4 3 Ill Figure 20. Proton NMR of (OE)34-PVL, 17 . :^^->-

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.,56 Table 4. Results of Polymerization of Ethylene Oxide (EO) with Initiator 11 V Under Various Conditions to Form Poly{oxyethylene) 17 Init. OE Mn Mn % moles moles Calc Obs M^/M^ Yield Conditions 0.010 0.20 1000 3780 1.03 82 25 ml THF, Ar, S^C 1 day, RT 2 days 0.010 0.20 1000 1660 1.13 88 25 ml THF, Ar, 5»C 3 days 0.010 0.20 1000 1610 1.10 85 100 ml THF, Ar, 5°C 3 days 0.010 0.20 1000 1570 1.10 60 25 ml THF, Ar, 5»C 2 days 0.005 0.10 1000 1590 1.05 84 50 ml THF, Ar, 0.005 moles 18-crown-6, 5°C 3 days 0.005 0.10 1000 6430 65 50 ml TMEDA, Ar, 5<'C 4 days 0.012 0.22 890 1050 1.30 83 100 ml THF, vacuum, 5°C 3 days Maintaining the reaction at 5"'C for 3 days produced r? with a lower molecular weight, M^ = 1660, and a higher molecular weight distribution, M^^/M^ = 1.13. About the same results were obtained with the use of 4 times the amount of tetrahydrofuran solvent. Decreasing the reaction time to two days at 5»C resulted in a lower molecular weight 17, M^ = 1570, in lower yield. The addition of 18-crown-6 gave the best results, producing 17 with M^ = 1590 and M^/M^ = 1.05 in good yield, 84%. This polymer, 17, has an average of 34 ethylene oxide repeat units, n. The use of N,N,N' ,N ' -tetramethylethylenediamine produced a high molecular weight 17, M^ = 6430, in low

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57 yield. Polymerizing ethylene oxide in a sealed reaction flask under vacuum at 5°C produced a good yield of 12 with Mn = 1050; however, the polydispersity of this material was very large, M^/Mn = 1.30, and the molecular weight was too low to precipitate from diethyl ether. Control of the Hard-Segment Length Once 12 is formed, the polymerization of pivalolactone to build the hard segment of the telechelomer is straightforward. The acidic proton is easily removed with potassium hydroxide in methanol to form the carboxylate salt, which is used to polymerize pivalolactone in tetrahydrofuran, under argon. The poly (pivalolactone) hard-segment length is controlled by the ratio of carboxylate to pivalolactone, and (OE)n-(PVL)jn telechelomers were synthesized with a constant poly(oxyethylene) soft-segment length, n = 34, and varying poly (pivalolactone) hard-segment length, m = 5, 12, and 16. The proton NMR of (OE) 34-(PVL) ^g (Figure 21) is identical to the proton NMR of (OE)34-PVL (17) (Figure 19), except for the heights and integrations of the poly (pivalolactone) singlets at 4.6 (b) and 1.2 ppm (c) . The poly(pivalolactone) segment length (m) is easily determined by proton NMR integration and verified by SEC analysis, using the Mark-Houwink parameters from the (PVL)jn-(OE)24-(PVL)in oligomers. ^ ^.-

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m '.«jf^-.' • ,. 1. H3C o "*l II H--(OCH2CH2)34 (OCH2— C-C)is-OH V H,C i /L '^$^ ym ' I ' I ' ' I I I I I I 4 3 I I I' I I I I I I I 2 1 Figure 21. Proton NMR of (OE) 34-(PVL) ^g, i:^: f ., .%L.

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i^iy^W. '£>_ '^'"^'^•Analysis of Microphase Separation Figure 22 presents the DSC curves of the (OE) 34-(PVL)jn defect-free telechelomers. Each sample shows a weak glass transition around -50°C and two melting endotherms, a high temperature endotherm for the hard phase and a lower temperature endotherm for the soft phase. Although the samples were quenched from 50 °C, the soft phase of these telechelomers exhibit crystallization, indicating that a high degree of microphase separation exists. Because the soft phase of these samples are semicrystalline, they do not lend themselves to the type of soft phase analysis used for the triblock oligomers. The Tq°^^ is not a reflection of the soft segment purity since only the non-crystalline soft segments participate in TgO'^^ and, when crystallization occurs, the amorphous regions are due to chain folding and microphase mixing at the interface. Also, calculation of the soft segment segregation assumes that the entire soft phase participates in the change in heat capacity at TgO^s. ^ ^^^ .^^ , ^ ^ ^ ^^ _,^ The hard-segment crystalline sequence propagation probability, p^ (Equation 12), was a good approximation of SRh for the (PVL)in-(OE)24-(PVL)in oligomers, and the calculated values of p" for the (OE) 34-(PVL)jn defect free telechelomers (Table 5) show that the sample for m = 12 and 16 have very high hard-segment purity. The 0.73 value of p^ for (OE) 34-(PVL)5 indicates that hard segment microphase mixing occurs in this sample. ,-: •

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«0 T u o •o c u i^" 100 T "T 100 Temperature ("C) 200 Figure 22. DSC Scans of (OE) 34-(PVL)m. K.r -••

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rr*P^_^i'r —I 7w: ~yr^ . ', -•' * .' <-*> ->"'f>**;n"?v Because the soft phase of the (OE) 34-(PVL)ji telechelomers also exhibit crystallization, Equation 12 can also be applied to the soft phase of these materials: pS = EXP[(l/TjnS l/Titt°J=S) .deltaH/R] (13) where Tj„^ represents the melting point of the soft-segment crystalline homopolymer, deltaH represents the heat of fusion per mole of repeat unit of the crystalline softsegment, and p^ represents the soft-segment crystalline sequence propagation probability. In this case, p^ should be a good approximation for Mgs* The values of p^ for the (OE) 3 4-(PVL) j„ telechelomers, listed in Table 5, were calculated from Equation 13 using a value of 1980 cal/mole of repeat unit for deltaH^^ and a value of 37. 4 "C for Tj^^.^^ The values of p^ for the (OE) 34-(PVL)m telechelomers are all greater than unity, indicating essentially complete softphase microphase separation occurs for the soft segments capable of crystallizing. Table 5. Results of DSC Analysis of Microphase Separation of (OE) 34-(PVL)m Defect-Free Telechelomers. Hard Phase Soft Phase m Wh rp obS Tm" pH m obs ^g rp obs pS 5 0.25 142°C 174»C 0.73 -50<»C 38°C 1.00 12 0.45 199»C 201''C 0.91 -53°C 42«»C 1.04 16 0.52 207»C 205°C 1.09 -52°C 50»C 1.13

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62 ' '' ' / ; Chapter Summary Defect-free telechelomers, (OE)n-(PVL)in, are produced by initiation with the dipotassium salt of hydroxypivalic acid in sequential anionic chain-propagation polymerization of ethylene oxide and pivalolactone. The DSC analysis of microphase separation of (OE) 34-(PVL)jn defect-free telechelomers indicate that these materials exhibit excellent microphase separation, allowing both the hard and soft segments to crystallize. Essentially complete microphase separation occurs for m = 12 and 16. In the case for m = 5, the hard segment is the minor component, and microphase separation is not complete.

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?.3f?--' STEP POLYMERIZATION OF TELECHELOMERS r^fer. Introduction The (OE) n" (PVL) j„ telechelomers exhibit excellent microphase separation; however, they do not have thermoplastic characteristics due to their low molecular weights and lack of more than one hard segment per polymer molecule. The step polymerization of the telechelomers to [(OE)^(PVL)ju]p segmented copolymers (Figure 23) represents an important aspect in the synthesis of poly (oxyethyleneblock pivalolactone) thermoplastic elastomers. The gem-dimethyls that give the poly(pivalolactone) hard segment excellent solvent resistance also make the sterically hindered carboxylic acid very difficult to step polymerize. Wagener and Wanigatunga^^ were unable to polymerize pivalolactone based telechelomers using a number of standard solution polyesterification reagents, including l-methyl-2-bromopyridinium chloride/tri-n-butylamine, N,N'bis (2-oxo-3-oxo-azolidinyl)phosphorodiamidic chloride/triethylamine, triphenyl phosphite, hexachlorocyclotriphosphatriazene, trif luoroacetic acid/methylene chloride, and methylsulfonic acid/phosphorus pentoxide. Several attempts at melt esterif ications also were unsuccessful, including heating without catalyst and heating with antimony trioxide or titanium tetrabutoxide. 63

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m H3C o H-COCHaCHaln (0CH2-C-C)„-0H H3C o H-|-(OCH2CH2)n (OCH2-C-C)„|-OH H-,C ((OE)„-(PVL)„Jp ^*frt Kif*'.-T/*'i'^ ^i f^ ^'} fT^ Figure 23. Step Polymerization of (OE)n-(PVL)jn to Segmented Copolymer [ (OE)ri-(PVL)ni]n' /" 7'* i"•;'«" •; \r c r(7 r;'Q

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:',..; ; _ , 65 . :;"' Wagener and Wanigatunga-^^ decided to attempt conversion of the hindered carboxylic acid end group to an unhindered carboxylic acid by reaction with d,l-alanine. However, after reaction with titanium tetrabutoxide at temperatures over 200°C, the d,l-alanine sublimed from the reaction melt upon application of vacuum, resulting in a segmented copolymer with a SEC M^ = 30,000 versus poly(styrene) . This reaction, termed alanine-mediated polymerization, is the first example of amino acid or zwitterionic catalyzed polyesterif ication. '"''''. Wagener, Wanigatunga, and Zuluaga^^ conducted a model study of the esterif ication of 2-(2-methoxyethoxy)ethanol with pivalic acid, and they observed a ten fold increase in the ester acid ratio with catalytic amounts of alanine at llO'C. Zuluaga conducted a detailed comparison of esterification by alanine alone, titanium tetrabutoxide alone, and alanine with titanium tetrabutoxide, and he observed that all three systems gave about the same ester acid product ratio. This study included esterification at llO^C under argon and at room temperature under vacuum, using 1 mole % of the catalysts; however, Zuluaga reports having difficulty obtaining reproducible results (Zuluage, F. personal communication) . Model Study In contrast to the original polyesterif ication conditions, the existing model studies involved the use of small organic molecules, 2-(2-methoxyethoxy)ethanol with pivalic T/Si^:

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, *. < 66 acid, and high temperatures and vacuum could not be applied simultaneously. In order to model polyesterification reactions more closely, a-hydroxypoly (pivalolactone) oligomers were examined under a number of different polyesterification conditions (Table 6) . The yields reported in Table 6 are the yields of polymer obtained from precipitating the crude product in diethyl ether from methylene chloride or N,N-dimethylacetamide. Low molecular weight poly (pivalolactone) , 500 g/mole or less, does not precipitate easily and is therefore separated from the isolated product. Thermogravimetric (TGA) analysis of a-hydroxypoly(pivalolactone) with M^ = 500 and 1180 g/mole (Figure 24) shows a marked difference in the thermal stability of the two poly (pivalolactone) oligomers. The lower molecular weight polymer (a) shows a long, slow decomposition that begins at very low temperatures, with 8% weight loss occurring at 200 °C. The higher molecular weight polymer (b) shows good thermal stability up to 200 °C and decomposes quickly after 300°C. In both cases, there is no evidence of esterification with the loss of water upon heating. The TGA results appear to indicate that the melt esterification of low molecular weight a-hydroxypoly (pivalolactone) should be conducted in two stages. The reaction should begin at the lowest possible temperatures to minimize decomposition. Then, after the dimer has formed, the polymer is more thermally stable, and higher temperatures could be utilized.

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m' ;r'-^ 200 300 Temperature ("C) 400 Figure 24. TGA Scans of a-Hydroxypoly(pivalolactone) with Mn = 500 (a) and M^ = 1180 (b) . 1^1 J r*n »^< \: ': ft-'' » , ' ^ M.« I >.tJtV ft i '•'> .•.'.''^ .

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Mpjrm-.'^ 68 3:^.; .; .•A. , ' Table 6. Results of Melt Polyesterif ication of a-Hydroxy-w-Hydropoly(pivalolactone) , (PVL)n, Under Various Conditions. Exp Initial Product # Mn % Yield M^ Conditions 1 500 10 «1000 Ti(0Bu)4 ^r 100»C 1 hr, Ar 100: ^ ' ' ., 150°C 0.5 hr, vacuum 150 <»C 0.5 .,_.;...V ,o-^\ ,^, , -.-,. hr „ , , ... „^^.,,. ._ 2 500 7 alOOO Alanine Ar lOO'C 1 hr, Ar 100,-. . 150'»C 0.5 hr, vacuum 150*'C 0.5 •-' --•—-• ^•^hr 3 500 20 «1000 Alanine Ar lOO'C 1 hr, vacuum 100°C 0.5 hr, Ti(0Bu)4 Ar 100-" "^ /: 150°C 0.5 hr, vacuum 150°C 0.5 ..,:...,.:?,''' :: _ hr 1180 Ti(0Bu)4 Ar 150-180<'C 1 hr, Ar 180-230»C 0.5 hr, vacuum 230°C hr 4 500 53 . 5 hr 5 500 51 1020 Alanine Ar 150-180''C Alanine Ar 150-180''C 1 hr, vacuum 180°C 0.5 hr, Ti(0Bu)4 Ar 180-230°C 1 hr, vacuum 230°C . 5 hr 6 1180 58 1270 Ti(0Bu)4 Ar 200'>C 1 hr, Ar 200^. , 250°C 0.5 hr, vacuum 250°C 0.5 hr , • --••">• "•,%:. . v In experiments 1, 2, and 3 in Table 6, melt ester if ications of a-hydroxypoly(pivalolactone) with M^ = 500 g/mole were conducted at temperatures between 100 and 150°C. In each case, however, only small amounts of the dimerized material were obtained, with titanium and d,l-alanine giving the highest yield, 20%. Proton NMR analysis indicates that substantial decomposition occurred in each case. No evidence of nitrogen was detected by proton NMR or elemental analysis of the products of reactions 2 and 3.

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}V m •_, r: . -...--; The melt esterif ications of a-hydroxypoly(pivalolactone) with M^ = 500 g/mole at higher temperatures. Experiments 4 and 5 in Table 6, produced dimerized product in yields around 50%. Titanium tetrabutoxide alone, Experiment 4, and titanium tetrabutoxide with d,l-alanine, Experiment 5, gave similar results; however, the numberaverage molecular weight of the product from experiment 5 is slightly lower due to the presence of low molecular weight polymer. Figure 25 presents the SEC traces of the starting material (a) and the products from Experiment 4 (b) and Experiment 5 (c) . Again, no evidence of nitrogen was observed for the product in Experiment 5. The melt esterif ication of a-hydroxypoly(pivalolactone) with Mn = 1180 g/mole, using alanine and titanium tetrabutoxide at 200-250»C, Experiment 6, resulted in decomposition and the recovery of starting material with slightly higher molecular weight and higher polydispersity, probably resulting from transesterif ication reactions. n n ? 1 1 Melt Esterification of Telechelomers Melt esterif ications of the (OE)n-(PVL)in telechelomers were attempted using l mole % titanium tetrabutoxide, with and without d,l-alanine, at temperatures between 180 to 250°C. Low molecular weight segmented copolymers, typically of the size of the dimer and trimer, were produced. In a single experiment, the pentamer of (OE) 34-(PVL) ^g/ Mn = 16,000 by SEC (Figure 26), was produced using titanium tetrabutoxide and d,l-alanine.

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^;rr;<»?r3«r7a5f?i'^y^' ,=v;' >:. <»,:=".?r 70 SEC PROGMNS Advanced Edition V:^^::^^ 9 Ml 10 11 12 13 Figure 25. SEC Analysis of Melt Esterification of a-Hydroxypoly(pivalolactone) : (a) Starting Material, Mn = 500, (b) Product of Titanium Catalyst (Experiment 4 Table 6), M^ = 1180, and (c) Product of Titanium Catalyst with d,l-Alanine (Experiment 5), Mn = 1020.

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v: i > j»4 :: V n *i .' , 71 »«--"• r-^<" SEC PROGRAMS Advanced Edition Figure 26. SEC Trace of (OE) 34-(PVL) 15 (a), Mn = 3,200, and [ (OE) 34(PVL) igls (b) , Mn = 16,000, >\:t(ts'.

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The methyl region of the proton NMR of [(OE)34(PVL)i6]5 product (Figure 27) contains several small peaks, evidence that this product contains a significant amount of partially decomposed poly(pivalolactone) segments. The DSC scan of [ (OE)34-(PVL)i6]5 is presented in Figure 28. The segmented copolymer produced from alanine-mediated melt ester if ication shows, relative to that of the original telechelomer in Figure 22, a slight decrease in the hardphase melting point with a large decrease in the heat of fusion, resulting in a much smaller signal. The melting point of the soft phase also decreased slightly, relative to that of the telechelomer. y.,, Chapter Summary Alanine-mediated melt esterif ication of the (OE)^(PVL)j„ defect-free telechelomers with titanium tetrabutoxide was successful in producing low molecular weight polymers containing a substantial amount of decomposed poly(pivalolactone) segment. ,. „' -.^ . > -i^,-* Model studies using low molecular weight a-hydroxypoly(pivalolactone) indicate that melt esterification of poly(pivalolactone) with titanium tetrabutoxide catalyst is not a viable route to high molecular weight step polymer.

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73 \ r-.: V H3C o H-|-(OCH2CH2)34 (OCH2— C~C) 16 H3C J -OH P , 5*.I I I < < I I I ' ' ' ' I ' ' ' ' I I ' I I I I I I I I ' ' I ' ' ' I Figure 27. Proton NMR of [ (OE) 34-(PVL) ^gls' r:^ r'^ r^ ib> i::^ ^^ ,..V'T W.J, *i. f-^t *~* «

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m w 1 I c -100 :.*»'K» Temperatiire CC) : -^ r ";u f-'^ • A^ ' U U'lH^ Figure 28. DSC Scan of [ (OE) 34-(PVL) igjs. 'V « 7 "».•

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:•: *-'." •'».' '-'»'STn»i" :::. EXPERIMENTAL f^^ Instrumentation . ^ .• . NMR data were obtained on a Varian XL-200, and all chemical shifts are reported in units of ppm down field from tetramethylsilane internal standard. Silanor-C or chloroform-d was used to make dilute solutions of the samples (about 0.003 g/ml) , and to samples containing poly(pivaiolactone) trif luoroacetic acid was added until a clear solution formed. All NMR sample solutions were filtered through glass wool prior to analysis. . . All DSC and TGA data were obtained on a Perkin-Elmer 7 Series Thermal Analysis System equipped with a TAC7 microcontroller and a PE7500 computer equipped with Perkin-Elmer TAS7 software. Both instrviments were calibrated by a two point method. The TGA was calibrated with nickel and perkalloy curie point standards with dry nitrogen purge gas (50 mL/min) . The DSC was calibrated with cyclohexane and indium with dry helium purge gas (25 ml/min) for subambient operations and with indium and tin with dry nitrogen purge gas (25 ml/min) for operation above 50<»C. Reported melting point temperatures represent the peak of the melting endotherm, and reported glass transitions represent the temperature of the midpoint of the glass transition. All reported DSC results are the average of 2-8 scans, at a rate

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of 20»C/inin, of each sample. In each case reported, the variance was less than 5%. All viscometry data were obtain on an Ace Scientific viscometer, ubderhalden type, using a Haake E2 constant temperature waterbath maintained at 30 ± O.Oloc. Gas Chromatograph data were obtained on a Hewlett Packard model 5880A Series Gas Chromatograph with accompanying 5880A Series Terminal, using Helium carrier gas and flame vaporization. Polymerizations of ethylene oxide were maintained at 5 ± l^C using a Precision Scientific Precision Lo-Temptrol low temperature bath containing Sears Antifreeze pumped through a copper coil immersed in an insulated isopropanol bath. Vacuum line experiments were performed on a high vacuum line (10"^ mmHg) constructed by the University of Florida Glass Shop using two Sargent Welch model D-1400 vacuum pumps, an Ace Glass mercury diffusion pump, two Ace Glass cooling traps, an Ace Glass mercury manometer. Ace Glass high vacuum stopcocks, and an argon inlet with mineral oil bubbler. Argon was passed through a concentrated sulfuric acid bubbler, a sodium hydroxide column, and a calcium sulfate column. "W v : .'; ^ ','':'"' All SEC data were obtained on a Waters 6000A Liquid Chromatograph, equipped with concentration sensitive differential refractometer detector. All data was collected and analyzed on a Zenith Personal Computer model 48 equipped with a MetraByte multi-IO card and an Epson dot matrix

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-.« >'' -' .' 77 printer. Sample solutions of 0.005 g/ml in methylene chloride containing 1% by volume trifluoroacetic acid were filtered through 0.45 nm filters and analyzed using TSK 5000 A and 3000 A columns. For analysis of poly (oxyethylene) polymers, the instrument was calibrated with narrow molecular weight distribution poly (oxyethylene) glycols. For analysis of Poly(oxyethylene-block-pivalolactone) polymers, the instrument was calibrated with narrow molecular weight distribution poly(styrene) standards by universal calibration. From the viscometry determination of [n] for the poly(styrene) standards (Table 7), the Mark-Houwink parameters for poly(styrene) in methylene chloride containing 1% trifluoroacetic acid were determined, K = 0.010 ml/g and a = 0.71, by a plot of Equation 2 (Figure 29). Table 7. Intrinsic Viscosities ([n]), Number-Average Molecular Weights (M^) , and Polydispersities (M^/M^) of Poly(Styrene) Standards Used for Universal SEC Calibration. 9000 17500 37000 48900 Mw/Mn TH^ 1.06 ^^H 1.06 y^?'i.06 1.06 • [n] dl/g 0.062 0.105 0.172 0.209 ''m^:-^.:'-i'^^. f -.' J-:

PAGE 85

7S 10 InM 11 Figure 29. Plot of Mark-Houwink Equation (Equation 2) for Poly(styrene) Standards Used for Universal SEC Calibration. v f rir'7 i f 'f\ --'^'..'&''

PAGE 86

^'^ SEC Programs > \~ General Description ' ~ The software for SEC data collection and analysis, entitled SEC Programs, was written by this author and compiled using Microsoft QuickBASIC compiler version 4.5, incorporating MetraByte's DASCONl.OBJ and some assembly language routines found in Cresent Software QuickPak Professional. The complete listing of SEC Programs is presented in the APPENDIX. SEC Programs is a menu-driven and user-friendly program that is capable of acquiring data, storing data, recalling previously stored data, analyzing data, calibrating the instrument, and printing data plots. SEC Programs has many advanced features including the simultaneous monitoring of the two detectors, automatic universal calibration, data exporting to an ASCII file, graphic display of up to 10 samples, automatic and manual rescaling, real-time graphic display of data acquisition, and run-time error checking. Additional time-saving conveniences include single-key menu selection, high-speed data plotting, and file directory display with file selection by arrow keys. Calibration ' * SEC Programs utilizes the peak position calibration method, or the Hamielec method, ^^ for narrow molecular weight distribution standards with known SEC peak molecular weights (Mp) and polydispersities according to the following equation: ^ ^-^ ..:,.:

PAGE 87

InMp = InD' D"'Vp :-../;':':;-.--: (i4) where Vp represents the measured SEC peak retention volume and D' and D" represent calibration constants. A plot of InMp versus Vp produces a line with slope = -D" and intercept = InD'. This linear calibration method is effective, provided that correlations greater than 0.99. obtained. Column spreading is then measured by reexamining the raw data for each calibration standard, and experimental values for the polydispersities (Mn®^/My,®^) are determined according to the following equations^^. M„®XP = S[F(V) -MCV) ] %i (15) Mn®^ = 1/2[F(V)/M(V)] (16) where F(V) represents the height of the normalized SEC curve at retention volume V and M(V) represents the molecular weight at retention volume V. The discrepancy between the true and the experimental molecular weight averages can be directly related to each other by a single Gaussian function correction factor, ^° and SEC Programs utilizes the Gaussian function correction factor to approximate instrumental peak broadening by a standard deviation (a) , which in the small range of the calibration standard elution is assumed to be independent of retention volume. The value of a is determined for each of the calibration standards, using the known Mwtrue/Mntrue and the calculated values of D" and Mwexp/Mnexp: a= [ln(Mw®^/Mn®^) ln(Mwtrue/Mj^true) ]1/2/d.. (^yj

PAGE 88

;. iT^i-^ Sample Analysis , -: Sample analysis by SEC Programs includes the Gaussian function correction factor, ^° which employs a, and the calibration constants D' and D": 5 Mv, = EXP[-(l/2) (D"-a)2] .S[F(V) •D''EXP(-D"«V)] (18) Mn = EXP[(l/2) (D"-a)2]/S[F(V)/D' •EXP(-D"V) ] (19) The column spreading can vary with retention volume^ ^; therefore, the user is prompted to input the value of a, based upon the calculated values of a the standards. Yau, Kirkland, and Bly*^ have shown that the error in the calculations of M^^ and M^ according to equations 18 and 19 are dependent upon the column parameters a and D": Error(M^,) = EXP[ (1/2) (a-D")2 i] (20) Error(Mn) = -EXP[-(l/2) • (a-D") 2 i] (21) And, in all SEC experiments, the error in molecular weight determination was less than 0.4%. -Chemicals All solvents used were reagent or HPLC grade. Tetrahydrofuran was refluxed over potassium-sodium alloy (2:1) overnight, distilled onto fresh potassium-sodium alloy (2:1), degassed and stored under reduced pressure for vacuum distillation into the reaction flask. N,N,N' ,N'-tetramethylethylenediamine was degassed, vacuum distilled onto calcium hydride and stirred overnight, vacuum distilled onto a potassium mirror, then vacuum distilled into the reaction vessel. Anhydrous diethyl ether was taken from freshly opened containers only. All solvents used in SEC and

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' 82 viscometry analysis were filter through 0.5 /xra filters prior to use. Purified water was obtained from a Milipore water purification apparatus. The narrow molecular weight distribution poly(oxyethylene) glycols were donated in pure form by Union Carbide. When needed dry, the poly(oxyethylene) glycols were dried under vacuum at 100 **C in a modified drying pistol for several days. Pivalolactone, donated in pure form by Dr. H. K. Hall, was dried over calcium hydride at reduced pressure overnight then distilled at reduced pressure just before use. Ethylene oxide (Aldrich) was cooled to -30<»C, opened in the hood and poured onto calcium hydride, degassed, vacuum distilled onto fresh calcium hydride, and stored under reduced pressure at -SO'C. Potassium metal (Aldrich) was cut in hexane, placed into a sidearm of the reaction flask, evacuated to high vacuum, and distilled directly into the reaction flask. Hydroxypivalic Acid (American Tokyo Kasie) was dried in a vacuum desiccator containing calcium sulfate for several days, transferred to an ampule containing a breakseal, dried by dynamic high vacuum for several days, and flame sealed in the ampule. Gold label 18-crown-6 (Aldrich) was used as received from unopened 1 g containers, and all transfers were done in a glovebag under argon. Reagent grade 18-crown-6 (Aldrich) was purified by precipitating its complex with nitromethane -:i 'X-

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and when removing the nitromethane with high vacuum. To a dried solution of 18-crown-6 in diethyl ether, nitromethane was added, forming a white precipitate that was filtered, placed into a vacuum desiccator under dynamic vacuum for several days, placed into a round-bottom flask, kept under dynamic high vacuum (10~^ mmHg) for several days, and stored under argon. Subsequent transfers were conducted in a glovebag under argon. Succinic anhydride (Aldrich) was dried under dynamic vacuum, sublimed under vacuum into an ampule containing a breakseal, flame sealed in the ampule, and sublimed directly into the reaction flask. D,l-Alanine (Aldrich) was reprecipitated from water, vacuum sublimed, and stored in a desiccator containing calcium sulfate. ... Titanium tetrabutoxide (Aldrich) was vacuum distilled and stored under argon. Standardized potassium hydroxide solutions in methanol were made from fresh containers of potassium hydroxide and standardized with dried potassium biphthalate with phenolphthalein indicator. Svntheses "^ 'i:. Synthesis of 7 ., . In a 250-ml round-bottom flask fitted with condenser, magnetic stirbar, and calcium sulfate drying tube, 10.0 g (10 mmoles) of poly(oxyethylene) glycol, 1000 g/mole, and 10.0 g (100 mmoles) of succinic anhydride were refluxed for

PAGE 91

'-'""''': ^* 24 hours in 100 ml of toluene with stirring. The toluene was removed by rotovap. The resulting white residue was dissolved in 100 ml of deionized water, stirred for 30 minutes, filtered, then extracted with four 25-ml portions of methylene chloride. The combined methylene chloride extracts were washed with two 25-ml portions of deionized water and dried over anhydrous sodium sulfate for at least two days before being filtered. The methylene chloride was rotovapped down to a concentrated solution and transferred to a drying pistol. The product was dried to a constant weight under vacuum while heating with refluxing water, resulting in a 92% yield. Molecular weight: 1260 (NMR) and 1260 g/mole (titration) . Elemental analysis: theoretical 52.7%C and 8.3%H, found 52.1%C and 8.4%H. Synthesis of 8 ..: After drying under high vacuum at lOO^C for several days, 1.15 g (0.91 mmoles) of 7 was dissolved in 75 ml of dry tetrahydrofuran by vacuum transfer. The flask containing 7 in tetrahydrofuran was sealed and attached to a 250-ml reaction flask containing a side arm for potassium metal and a magnetic stirbar. Approximately 1 g of potassium was placed into the side arm and the flask was flame sealed and taken to high vacuum. The potassium was distilled into the reaction flask under dynamic vacuum, forming a mirror, and the side arm was removed by flame sealing. The stopcock to the dynamic vacuum was closed and the tetrahydrofuran solution of 7 was allowed to pour onto the mirror, with

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immediate bubbling. The reaction was periodically degassed to remove hydrogen. After 24 hours, the tetrahydrofuran solution was decanted into a second round-bottom flask and rotovapped, resulting in 1.2 g of a white powder which was dried by high vacuum and stored under argon. Synthesis of (I>Vh) jj^ -(OE) j^ -(I>VL) j^ .. .. >^ Macromolecular initiator 8 was quickly weighed, 1.0 g, and placed into a round-bottom flask with stirbar and attached to the vacuum line. The flask was taken to high vacuum and 40 ml of dry tetrahydrofuran was vacuum transferred into the flask. This initiator solution, 0.020 mmoles/ml, was stored under argon. >> To a 250-ml round-bottom flask with magnetic stirbar under argon, was added 10 ml of the initiator solution by syringe. With stirring, pivalolactone, 9.9 mmoles/ml, was added by syringe to obtain initiator to monomer ratios of 1:5, 7, 9, 12, 16, and 24. The reaction stirred under argon overnight, and the product was isolated by evaporation of the tetrahydrofuran under reduced pressure. Elemental Analysis: (PVL)5-(0E) 24-(PVL) 5 theoretical 54.3%C, 7.9%H, and 3.3%K, found 54.6%C, 8.2%H, and 1.4%K; (PVL)7-(0E) 24(PVL)7 theoretical 54.8%C, 7.9%H, and 2.7%K, found 55.0%C, 8.1%H, and 1.3%K; (PVL)9-(0E) 24-(PVL)9 theoretical 55.5%C, 7.9%H, and 2.5%K, found 55.5%C, 8.3%H, and 1.1%K; (PVL) l2(0E) 24-(PVL) 12 theoretical 56.5%C, 8.0%H, and 2.0%K, found 55.7%C, 8.0%H, and 1.1%K; (PVL) ig" (OE) 24-(PVL) ^g theoretical 57.0%C, 8.0%H, and 1.7%K, found 55.3%C, 8.0%H, and 1.0%K;

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(PVL)24-(OE)24-(PVL)24 theoretical 57.7%C, 8.0%H, and 1.3%K, found 57.1%C, 8.0%H, and 1.0%K. Synthesis of 10 »^ ^,fl.^» U., .. : • In a dry box, 7.59 g (50 minoles) of t-butyldimethylsilyl chloride and 4.82 g (70 mmoles) of imidazole were place into a 250-ml round-bottom flask with magnetic stirbar. The flask was attached to the vacuum/argon line, and, under argon, 7.60 g (50 mmoles) of 2-benzoxyethanol and 25 ml of N,N-dimethylformamide was added by syringe. The reaction was stirred in an oil bath at SO'C for 30 hours. Then, 50 ml of hexane was added, the solution was transferred to a separatory funnel, and the solution was washed with four 25-ml portions of purified water. The organic layer was dried over anhydrous magnesium sulfate and filtered. The hexane was evaporated and the product was vacuum distilled at 1 mmHg and 140oc. 10.8 g, 80% yield, of a colorless oil was obtained in 97.3% purity by gas chromatography. . /-v^-' V . Synthesis of 11 -vJi*;^ In a high pressure flask, 10.0 g (37.5 mmoles) of 10 ,. 1.0 g of 10% palladium on charcoal, and 100 ml of dry tetrahydrofuran were mixed. The flask was placed into a Parr Shaker and hydrogenated for 24 hours at 30 psig until hydrogen uptake was complete. The resulting mixture was filtered and rotovapped. The product was isolated by distillation at 68 °C and 1 mmHg in 97.6% purity by gas chromatography.

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• ^ _ -;. ./%•' Synthesis of 12 Using vacuum-line and breakseal techniques, 2.0 g (10 minoles) of 11 was freeze-pump-thawed several times and sealed in a ampule. 11 was stirred by magnetic stirring in 50 ml of dry tetrahydrofuran over a potassium mirror for 3 days with periodic degassing. The precipitated product and the tetrahydrofuran were decanted into the receiving flask and flame sealed. * Synthesis of 13 A flask containing 2.0 g (10 mmoles) of 12 in 50 ml of dry tetrahydrofuran under vacuum was attached to the vacuum line, and 10 ml (200 mmoles) of ethylene oxide was vacuum transferred directly into the flask. The flask was given a static argon atmosphere, open to a mineral oil bubble to release any sudden pressure, and stirred at S^C for 3 days. The tetrahydrofuran was evaporated at reduced pressure and the residue was dissolved in 30 ml of purified water. Dilute hydrochloric acid was added until the solution tested positive to litmus paper. The water solution was extracted with four 20-ml portions of methylene chloride. The combined methylene chloride extracts were dried over calcium sulfate and then filtered. The methylene chloride was then poured into 500 g of cold diethyl ether forming a white precipitant which was immediately filtered and dried in a vacuum desiccator over calcium sulfate. The isolated yield was 1.6 q, 70% yield. <

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Synthesis of 14 /-'': To a reaction flask attached to the vacuum line, an ampule containing 1.0 g (5 mmoles) of 12 and 50 ml of tetrahydrofuran and an ampule containing 2.5 g (25 mmoles) of succinic anhydride were attached. 5 ml (100 mmoles) of ethylene oxide was vacuum transferred directly into the flask. The flask was given a static argon atmosphere, open to a mineral oil bubbler, and the initiator solution was allowed to polymerize ethylene oxide with magnetic stirring at 5°C for 3 days. Then, the succinic anhydride was sublimed directly into the flask, and the flask was allowed to warm to room temperature and stir overnight. The tetrahydrofuran was evaporated at reduced pressure and the residue was dissolved in 20 ml of methylene chloride. The methylene chloride was added to 250 g of diethyl ether forming a light brown precipitant in 80% yield. Synthesis of 16 Using vacuum-line and breakseal techniques, 1.2 g (10 mmoles) of dry hydroxypivalic acid was taken to high vacuum in an ampule. 25 ml of dry tetrahydrofuran was vacuum transferred directly into the ampule, and the ampule was flame sealed. ; . The ampule containing the hydroxypivalic acid in tetrahydrofuran was attached to a reaction vessel. In cases where 18-crown-6 was used, a second ampule containing 5 mmoles of 18-crown-6 in 10 ml of tetrahydrofuran was also attached. Approximately 1 g of potassium was placed into a C -. ^. w Wk .

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.^ ;•' ' ^ "^ !»T^?rTyT'/^' side arm, and the flask was flame sealed and taken to high vacuum. The potassium was distilled into the reaction flask under dynamic vacuum, forming a mirror, and the side arm was removed by flame sealing. The stopcock to the dynamic vacuum was closed and the contents of the ampule (s) were allowed to mix. The reaction was stirred by magnetic stirring for 3 days with periodic degassing. The precipitated product and the tetrahydrofuran were decanted into a receiving flask and flame sealed. General Procedure for Dual-Anionic Polymerization In a typical experiment using vacuum line and breakseal techniques, 5 ml (100 mmoles) of ethylene oxide is vacuum transferred into a 250-ml reaction vessel, at dry ice/isopropanol temperature, containing a magnetic stirbar and having attached ampules containing 1) 0.04 moles (2.5 ml) of pivalolactone and 2) 0.005 moles 16 in 25 ml of tetrahydrofuran. The contents of the ampules are allowed to mix in the reaction vessel, magnetic stirring is begun, and the reaction temperature is maintained at 5°C by a constant temperature bath. The reaction is given a static argon atmosphere with a valve to release any sudden pressure. After two days, the reaction vessel is evacuated to remove tetrahydrofuran and any unreacted pivalolactone and ethylene oxide. The product is isolated by hydrolysis, extraction with methylene chloride, and precipitation in diethyl ether.

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-;.-.. 90 ".... --^•;' General Procedure for Sequential Addition Polymerization In a typical experiment using vacuum line and breakseal techniques, 10 ml (200 mmoles) of ethylene oxide is vacuum transferred into a 250-ml reaction vessel containing a magnetic stirbar and having an attached ampule containing 10 mmoles of 16 in 25 ml of tetrahydrofuran. The contents of the ampule is mixed in the reaction vessel, magnetic stirring is begun, and the reaction temperature is maintained at 5°C by a constant temperature bath. The reaction is given a static argon atmosphere open to a mineral oil bubbler to release any sudden pressure. After two to three days, the reaction vessel is evacuated to remove tetrahydrofuran and any unreacted ethylene oxide. The reaction vessel is removed from the vacuum line, and the solid residue is dissolved in water, acidified with dilute hydrochloric acid, and extracted with four 25-ml portions of methylene chloride. The methylene chloride extracts are combined, dried over magnesium sulfate, and added to 500 g of cold diethyl ether, precipitating polyether 17 . 1 g of 17 is dissolved in methanol and titrated with 0.01 N potassium hydroxide in methanol with phenolphthalein as an indicator. The solution is then rotovapped and the residue, 18 dried in a drying pistol. Under argon, the salt 18 is reacted with pivalolactone in a molar ratio based upon the amount of base needed in the titration, in 25 ml of dry tetrahydrofuran. After 1 day, the reaction is evacuated to remove tetrahydrofuran and unreacted pivalolactone.

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91 ,..'' Methylene chloride is added to dissolve as much of the residue as possible. The resulting solution is shaken with 3 N hydrochloric acid and separated. The (OE)n-(PVL)j„ telechelomer is isolated by precipitation in diethyl ether or by evaporation of the methylene chloride solvent. General Procedure for Alanine-Mediated Step Polymerization The telechelomer and an equal molar amount of d,lalanine are placed in a three-necked polymerization reactor fitted with mechanical stirrer, argon/ vacuum inlet, and syringe inlet with stopcock. The flask is evacuated and maintained at a slightly elevated temperature to dry the contents. Then the flask is given an argon atmosphere and heated to 20000 by a salt bath. After the telechelomer melts, mechanical stirring is begun, and the reaction mixture is stirred for 1 hour. The flask is evacuated for 1/2 hour at 200"C to remove any unreacted d,l-alanine. One mole percent titanium tetrabutoxide is added by syringe to the reaction, and the reaction temperature is slowly increased to 250"C over a period of 1 hour. Then, vacuum is applied at 250»C for 1/2 hour. The reaction is allowed to cool, and the resulting product is dissolved in methylene chloride — or dissolved in boiling N,N-dimethylformamide and cooled — and added to a large volume of diethyl ether. The product is isolated by filtration and dried in a vacuum desiccator. -

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'"''. '.v' :, REFERENCES :. .• "^L. 1. McGrath, J. E. In Block Copolymers. Science and Technology ; Meier, D. J., Ed.; Hardwood Academic Publishers: New York, 1983; p 1. 2. Schollenger, C. S.; Scott, H.; Moore, G. R. Rubber World . 1958, 137, 549. -. 3. Miller, J. A.; McKenna, J. M. ; Pruckmayr, G. ; Epperson, J. E.; Cooper, S. L. Macromolecules . 1985, 18, 1727. 4. Leung, L. M. ; Koberstein, J. T. Macromolecules , 1986, 19, 706. -: 5. Brunette, C. M. ; Hsu, S. L. ; Rossman, M. ; MacKnight, W. J.; Schneider, N. S. Polym. Ena. Sci. . 1981, 21,, 668. 6. Camberlin, Y.; Pascault, J. P. J. Polym. Sci.. Polym. Chem. Ed. . 1983, 21, 415. 7. Pascault, J. P.; Camberlin, Y. Polym. Comm. ^ 1986, 27, 230. V r 8. Senich, G. A.; MacKnight, W. J. Adv. Chem. Ser. . 1979, 176 . 97. , /: " 9. Wolfe, J., Jr. Rubber Chem. Technol. . 1977, 50(1)/ 230. 10. Wolfe, J., Jr. Adv. Chem. Ser. . 1979, 176 . 129. 11. Wolfe, J., Jr. In Block Copolymers Science and Technology ; Meier, D. J., Ed.; Hardwood Academic Publishers: New York, 1983; p 145. 12. Droescher, M. ; Bandara, U. ; Schmidt, F. Macromol. Chem. Phvs . SuDPl . . 1984, 7, 107. 13. Droescher, M. ; Schimdt, F. G. Makromol. Chem. . 1983, 184 . 2669. 14. Miller, J. A.; Lin, S. B.; Hwang, K. K. S.; Wu, K. S.; Gibson, P. E.; Cooper, S. L. Macromolecules . 1985, 18, 32. 15. Jelinski, L. W. ; Schilling, F. C. ; Bovey, F. A. Macromolecules ^ 1981, 14, 581. 92

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16. Morese-Seguela, B.; St-Jacques, M. ; Renaud, J. M. ; Prud ' homme , J. Macromolecules . 1980, 13, 100. 17. "Reactions on Polymers Symposium." Polymer Preprints . 1989, 30(2) . 18. Hashimoto, T. ; Mitsuhiro, S.; Fujimura, M. ; Kawai, H. In Block Copolymers. Science and Technology ; Meier, D. J. , Ed.; Hardwood Academic Publishers: New York, 1983; p 63. 19. Leibler, L. Macromolecules . 1990, 13., 1602. 20. Wagener, K. B. ; Thompson, C; Wanigatunga, S. Macromolecules . 1988, 11, 2668. 21. Wagener, K. B.; Wanigatunga, S.; Matayabas, J. C. , Jr. Macromolecules . 1989, 22., 3211. 22. Yamashita, Y.; Tsuda, T. ; Ishida, H.; Uchikawa, A.; Kuriyama, Y. Makromol. Chem. . 1968, 113 . 139. 23. Yamashita, Y.; Toshioki, H. J. Polym. Sci.. Polym. Chem. Ed. . 1973, 11, 425. 24. Jedlinski, Z.; Kurcok, P.; Kowalczuk, M. Macromolecules . 1985, 18, 2679. .^ 25. Lenz, R. ; Bigdelli, E. Macromolecules . 1978, 11, 493. 26. Hall, H. K. Jr. Macromolecules . 1969, 2, 488. 27. Wilson, D. R. ; Beaman, R. G. J. Polvm. Sci.. A-l , 1970, 8, 2161. 28. Osterhof, H. A. Polymer, 1974, 15, 49. 29. Borri, C. ; Bruckner, S.; Crescenzi, V.; Delia Fortuna, G.; Mariano, A; Scarazzato, P. Eur. Polvm. J. . 1971, 7, 1515. 30. Prud'homme, R. E. ; Marchessault, R. H. Makromol. Chem. . 1974, 175, 2705. . . 31. Meille, S. v.; Konishi, T. ; Geil, P. H. Polymer, 1984, 25, 773. ,, _^. , , , 32. Caywood, S. W. Rubber Chemistry and Technology . 1977, 50, 127. 33. Foss, R. P.; Jacobson, H. W. ; Cripps, H. N. ; Sharkey, W. H. Macromolecules . 1979, 12, 1210. 34. Harris, J. F., Jr.; Sharkey, W. H. Macromolecules . 1977, 10, 503. _

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d4 35. Yusada, T. ; Aida, T.; Inoue, S. Macromolecules . 1984, ZQ., 1717. 36. Wagener, K. B.; Wanigatunga, S. Macromolecules . 1987, 20., 1717. 37. Wagener, K. B. ; Wanigatunga, S. In Chemical Reactions on Polymers ; Benham, J. L. , Kinstle, J. F., Eds.; American Chemical Society: Washington, DC, 1988; p 153. 38. Wagener, K. B. ; Wanigatunga, S. Macromolecules , 1989, 22, 2090. 39. Price, G. J.; Moore, J. W. ; Guillet, J.E. J. Polym. Sci. ; Part A . 1989, 27, 2925. 40. Kilp, T. ; Guillet, J. E. Macromolecules . 1977, 10, 90. 41. Solomon, 0. F. ; Ciuta, I. Z. Bull. Inst. Pol it. Gh. Gh. Dei. Buc. . 1968, 20, 3. 42. Yau, W. W. ; Kirkland, J. J.; Bly, D. D. Modern SizeExclusion Liquid Chromatography . John Wiley & Sons, New York, 1979. 43. Dondos, A.; Rempp, P.; Benoit, H. Macromol . Chem . ^ 1974, 175, 1659. 44. Turi, E. A. Thermal Characterization of Polymeric Materials . Academic Press, New York, 1981. 45. Wood, L. A. J. Polvm. Sci. . 1958, 28, 319. 46. Gordon, M. ; Taylor, J. S. J. Appl. Chem. . 1952, 2, 493. 47. Dimarzio, E. A.; Gibbs, J. H. J. Polym. Sci. . 1959, 60, 121. i_.-, ; •"V ' ';^ 48. Couchman, P. R. ; Karasz, F. E. Macromolecules . 1978, 11, 117. ^?.r fs.. r'f ^; ri^J y'[i 49. Kelly, F. M. ; Bueche, F. J. Polvm. Sci. . 1961, 50, 599. », . } 50. Wagener, K. B.; Matayabas, Jl C. Jr. Polymer Preprints , 1989, 30(2) , 243. 51. Wagener, K. B. ; Matayabas, J. C. Jr. J. Chem. Ed. ^ 1988, 65, 557. 52. Mandelkern, L. , Ed. Crystallization of Polymers . McGraw-Hill, New York, 1964; p. 79. 53. O'Malley, J. J. J. Polym. Sci.. Poly. Phys. Ed. . 1975,

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'fK^s^» v^^ "^wr 9B ne:13, 1353. 54. O'Malley, J. J.; Staffer, W. J. Polvm. Ena. Sci. . 1977, 17, 510. 55. Borri, C; Bruckner, S.; Cresenzi, V.; Fortuna, G. D.; Mariano, A.; Scarazzato, P. Eur. Polvm. J. . 1971, 7, 1515. 56. Hirao, A.; Kato, H. ; Yamaguchi, K. ; Nakahama, S. Macromolecules ^ 1986, 19, 1294. 57. Mandelkern, L. ; et al. J. AppI. Phvs. . 1955, 26, 443. 58. Wagener, K. B.; Wanigatunga, S.; Zuluaga, F. Polymer Preprints . 1989, 31(1), 5. 59. Tanford, A. Physical Chemistry of Macromolecules , Wiley, New York, 1961, p. 407. 60. Dawkins, J. V. J. Macromol. Sci. . 1968, B2, 623. 61. Tung, L. H. ; Runyon, J. R. J. AppI. Polym. ScL ^ 1969, 13, 2397. ; ^r >, f-'K' f'T' "• •• •*. n i 7 « / : i5 • • • • *•' " ' •• i" ^j ^ . v« y .. s '^\j \ i ^l if:r . '^ • J I • / " * f. , , >w V

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'» ' , APPENDIX ' ' * ' * DECLARE SUB CalPlot (M! , B! , y!(), X! () , Stand$(), Ans%) DECLARE FUNCTION SelectFile% (Ext$) ••^DECLARE FUNCTION FCount% (Ext$) DECLARE FUNCTION DOSError% () ********************************************************** SEC Programs BASIC program listing. It should be * compiled with Microsoft QuickBASIC compiler version 4.5 * and linked with SEC. LIB, which is a library containing * MetraByte DASCONl.OBJ and some assembly language * routines from Cresent Software QuickPak Professional. * * SEC Programs is the data collection and analysis * program for the Polymer Floor SEC instrument at the * University of Florida. * Written by J. C. Matayabas, Jr. * ********************************************************** ********************************************************** Part I. Program Initialization. * ********************************************************** DIM TData AS INTEGER, RunLength AS INTEGER DIM MaxSignal AS INTEGER, Counter AS INTEGER DIM Chnl AS INTEGER, Dat(2404) AS INTEGER DIM FlowRate AS SINGLE, Dl AS SINGLE, D2 AS SINGLE DIM StandF(lO) AS STRING, DIM RunEnd AS INTEGER DIM Area AS SINGLE, Suml AS SINGLE, Sum2 AS SINGLE DIM Mp AS SINGLE, Mn AS SINGLE, Mw AS SINGLE DIM CalFile AS STRING, XXI AS INTEGER, XX2 AS INTEGER DIM XI AS INTEGER, X2 AS INTEGER, YYl AS INTEGER DIM YY2 AS INTEGER, Yl AS INTEGER, Y2 AS INTEGER DIM FileName AS STRING, FileSpec AS STRING, AnyKey AS STRING DIM MwMn AS SINGLE, Peak AS INTEGER, Valley AS INTEGER DIM Number 1 AS INTEGER, Number 2 AS INTEGER, Number AS SINGLE DIM Dio(8) AS INTEGER, Md AS INTEGER, Ch AS INTEGER DIM BasAdr AS INTEGER, Sigma AS SINGLE, LogMp(lO) AS SINGLE DIM VMp(lO) AS SINGLE, Slope AS SINGLE, Intercept AS SINGLE DIM Correlation AS SINGLE DIM SHARED Stand$(10), Flag AS INTEGER DIM Dat2Max AS INTEGER, Dat2Min AS INTEGER, Chnl2 AS INTEGER DIM Dat2(2404) AS INTEGER, Mass AS SINGLE DIM SData(607) AS INTEGER DEFINT N: SCREEN 0: CLS FlowRate =1/60: RunLength = 2400: Chnl = 0: Chnl2 = 4 MaxSignal = 2000: CalFile = "**" 96

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• Part II. Setup and Run Routine. Main Menu. * Setup : ERASE Dat, Dat2 : CLS 0: SCREEN 2: VIEW PRINT 1 TO 25 LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition" PRINT USING "Flow: #.# ml/min Run: ##.# inl";_ FlowRate * 60; RunLength * FlowRate; PRINT USING " Y-Max: #### mV Chnl: #"; MaxSignal; Chnl; IF Chnl2 <> 4 THEN PRINT USING "_, #"; Chnl2 ; PRINT USING " Cal: &"; CalFile; VIEW (20, 20) -(620, 172), , 7 ^ Numberl = -.15 * MaxSignal: WINDOW (0, Numberl) -(RunLength, MaxSignal) SELECT CASE RunLength * FlowRate CASE IS > 160 V Number = 40 / FlowRate , CASE IS > 80 Number = 20 / FlowRate CASE IS > 40 Number = 10 / FlowRate CASE IS > 20 Number = 5 / FlowRate ^ CASE IS > 10 .: Number = 2 / FlowRate CASE ELSE Number = 1 / FlowRate END SELECT FOR Counter = TO RunLength STEP Number LINE (Counter, Numberl) -(Counter, Numberl * 5 / 6) Number 2 = ((Counter / (RunLength * 8)) * 600) + 2 LOCATE 23, Number2 : PRINT USING "##"; Counter * FlowRate NEXT Counter LOCATE 23, 5: PRINT "ml": VIEW PRINT 24 TO 25 PRINT " = Recall Cal Curve = Create Cal Curve _ = Recall File" PRINT " = MultiPlot

= Change Parameters _ = Run Sample = Exit"; ^,, MainMenu: i' SELECT CASE UCASE$ (INPUT$ (1) ) *i • Exit Chosen. ""^^ ' ' CASE CHR$(27) END -ri f'n-.y^li q-^. ' Recall Cal Curve chosen. • w,* ' -vJ** -i CASE "B" Ans% = SelectFile%(".CAL") : IF Ans% <> 1 THEN GOTO SetUp CalFile = Stand$(l) OPEN "B:" + CalFile + ".CAL" FOR INPUT AS #1 INPUT #1, Dl, D2: CLOSE #1: GOTO SetUp ' Create Cal Curve chosen. CASE "C" Ans% = SelectFile%(".STD") : IF Ans% = THEN GOTO SetUp IF Ans% < 2 THEN ...... CLS : PLAY "L32ECEC" v ' ' ;'^ '

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m PRINT "You Must Select 2 or More Files." ^ \ PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1): GOTO Setup END IF PRINT "Calculating, Please Wait. . ."; FOR N = 1 TO Ans% ERASE SData: StandF(N) = "B:\" + Stand$(N) + ".STD" CALL QBLoad(StandF(N) , SEG SData(O)) FlowRate = SData(601) / 6000 Mp = SData(602): Mp = Mp * 30000 + SData(603) MwMn = SData (604) / 100: Peak = SData (605) .;* LogMp(N) = LOG(Mp): VMp(N) = Peak * FlowRate '^NEXT N , ! ' Ex = 0: Exx = 0: Ey = 0: Eyy = 0: Exy = FOR N = 1 TO Ans% Ex = Ex + VMp(N) : Exx = Exx + VMp(N) " 2 Ey = Ey + LogMp(N): Eyy = Eyy + LogMp(N) " 2 Exy = Exy + VMp(N) * LogMp(N) NEXT N SSx = Exx (Ex ~ 2 / Ans%) : SSy = Eyy (Ey " 2 / Ans%) SSxy = Exy (Ex * Ey / Ans%) : Slope = SSxy / SSx Intercept = (Ey / Ans%) (Slope * (Ex / Ans%) ) Correlation = SSxy / SQR(SSx * SSy) IF Correlation < THEN Correlation = -Correlation Dl = EXP ( Intercept ) : D2 = -Slope CLS : PRINT "Calibration Results:": PRINT PRINT "Standard Mp Mw/Mn Sigma LnMp Vmax" FOR N = 1 TO Ans% ERASE SData: CALL QBLoad (StandF(N) , SEG SData(O)) FlowRate = SData (601) / 6000 Mp = SData(602): Mp = Mp * 30000 + SData(603) MwMn = SData(604) / 100: Peak = SData (605) : XI = SData(606) X2 = SData (607): Area = 0: Suml = 0: Sum2 = FOR Counter = XI TO X2 Numberl = Counter XI: TData = SData (Numberl) Area = Area + TData: Mass = Dl * EXP(-D2 * Counter * FlowRate) ~ Suml = Suml + (TData / Mass) ' , , Sum2 = Sum2 + (TData * Mass) ^ ;. NEXT Counter CLOSE #1: Mn = Area / Suml: Mw Sigma = Mw / Mn: Sigma = Sigma IF Sigma <= 1 THEN Sigma = Sigma / D2 PRINT USING "\ \ MwMn ; PRINT USING " #.### ###.## ###.##"; Sigma; LogMp(N);_ / Sum2 / Area MwMn Sigma = ELSE Sigma = SQR(LOG(Sigma) ) ##.##"; Stand$(N); Mp;_ Vi-a*^ *i..r^r 'I--' VMp(N) k;^«.v'''-? '» ^-v«w NEXT N ' PRINT : PRINT USING "Slope -^-^^ = ##.###"; -D? PRINT USING "Intercept = ###.##"; Intercept PRINT USING "Correlation = #.####"; Correlation ' -i,y .-?«.

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IF D2 <= OR Correlation < .9 THEN PLAY "L32ECEC": PRINT PRINT "One or More of Your Standard Files Do Not Correlate." PRINT "This is Not a Valid Calibration. Please Recheck Your Data." PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1): GOTO SetUp END IF ' . -. IF Correlation < .99 THEN . -, PLAY "L32ECEC": PRINT : ' PRINT "The Correlation is Poor, and This May Not Be a Valid_ Calibration. " PRINT "The Calibration Range May be Too Large. Please_ Recheck Your Data . " PRINT "Press Any Key to Continue "; AnyKey = INPUT$(1): PRINT END IF PRINT : PRINT "Press Any Key to View Graph..."; AnyKey = INPUT$(1) CALL CalPlot(-D2, Intercept, LogMp(), VMp() , Stand$(), Ans%) VIEW PRINT 24 TO 25: CLS 2 PRINT "Do you want to save this calibration curve (Y/N)? "; AnyKey = UCASE$(INPUT$(l) ) : PRINT AnyKey IF AnyKey = "N" THEN GOTO SetUp PRINT "Saving Calibration Curve " Ext$ = ".CAL": GOSUB GetName: OPEN FileSpec FOR OUTPUT AS #1 WRITE #1, Dl, D2: CLOSE #1: CalFile = FileName VIEW PRINT 2 TO 2: CLS 2 LOCATE 2, 28: PRINT USING "Calibration Curve &"; FileName; VIEW PRINT 24 TO 25: CLS 2 PRINT "Press

to Plot or Any Other Key to Continue..."; AnyKey = UCASE$(INPUT$(1) ) IF AnyKey = "P" THEN CLS 2: PRINT USING " Slope = ##.###"; -D2 ; PRINT USING " Intercept = ###.##"; Intercept; PRINT USING " Correlation = ##.####"; Correlation; CALL ScrnDump("", 1, 0) END IF 1 " Y •;• ' ' GOTO Setup ' ll U'iifOt x^ -1 -1 t, • 1 ,_ M i *^-.--.»!-^«^ ^Tilts' V •• ' Recall File chosen. CASE "F" Ans% = SelectFile%(".SEC") : IF Ans% = THEN GOTO SetUp FileName = Stand$(l): FileSpec = "B:" + FileName + ".SEC" CLS 2: PRINT "Recalling File. Please Wait..."; CALL QBLoad (FileSpec, SEG Dat(O)) FlowRate = Dat(2401) / 6000: RunEnd = Dat(2402) DatMax = Dat(2403): DatMin = Dat(2404) Numberl = .1 * Dat (DatMax) : YY2 = Dat (DatMax) + Numberl YYl = Dat (DatMin) Numberl: IF YYl >= THEN YYl = -Numberl XXI = 0: XX2 = RunEnd: GOSUB ReDraw " CASE "M" Ans% = SelectFile%(".MPT") : IF Ans% = THEN GOTO SetUp PRINT "Select Volume Range (ml):" INPUT "Enter Volume Minimum: ", XXI

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^^T^^J^t^ "^^'?^~ -^ -" '"j.'W^'^^j^-. .^.-'^ "fijf:'?;*^^^" 100 INPUT "Enter Volume Maximum: ", XX2 IF XXI >= XX2 THEN PLAY "L32ECEC": GOTO SetUp . CLS 0: SCREEN 2: VIEW PRINT 1 TO 25 LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition" VIEW (20, 20)-(620, 172), , 7 , .. , *, WINDOW (XXI, -100)-(XX2, 1100) .'-i^ SELECT CASE (XX2 XXI) '. CASE IS >= 20 o i ' : =" Numberl =5 ' . CASE IS >= 10 Numberl =2 .^ CASE ELSE , V V ;. ; ,, F Numberl = 1 ... ;•; ' END SELECT ' " ; FOR Counter = XXI TO XX2 STEP Numberl LINE (Counter, -100) -(Counter, -50) N = ((Counter XXI) / ( (XX2 XXI) * 8) * 600) + 2 LOCATE 23, N: PRINT USING "##"; Counter; NEXT Counter LOCATE 23, 5: PRINT "ml"; ^"H>; : FOR Counter = 1 TO Ans% > FileSpec = "B:" + Stand$ (Counter) + ".MPT" ; OPEN FileSpec FOR INPUT AS #1 Peak = 0: INPUT #1, Volume, VData: PSET (Volume, VData) DO UNTIL EOF(l) INPUT #1, Volume, VData: LINE -(Volume, VData) IF VData > Peak THEN Peak = VData: Number = Volume LOOP CLOSE #1 N = ((Number XXI) / ((XX2 XXI) * 8) * 600) + 2 IF N < 4 THEN N = 4 ELSE IF N > 76 THEN N = 76 LOCATE 4, N: PRINT USING "#"; Counter la^' NEXT Counter LOCATE 2, 1 ^ ,X ^. ^ FOR Counter = 1 TO Ans% .. tj^.^^ f 1^. IF Counter = 6 THEN LOCATE 24, 1 PRINT USING "##: & "; Counter; Stand$ (Counter) ; NEXT Counter '. i "j,^-^ f ? :., v»» ' ^ VIEW PRINT 24 TO 25 LOCATE 25, 1: PRINT "Press

to Print or Any Other Key to Continue..."; yv .; ^ AnyKey = UCASE$(INPUT$(1) ) IF AnyKey = "P" THEN CLS 2: CALL ScrnDump("", 1, 0) GOTO Setup ,'' Change Parameters chosen. ,^ , CASE "P" ' '-'--'' ^-' -' CLS 2: INPUT "Enter flow rate (ml/min) : ", Number IF Number <> THEN FlowRate = Number / 60 INPUT "Enter length of run (ml): ", Number ' Number = Number / FlowRate IF Number >= 100 AND Number <= 2400 THEN RunLength = Number INPUT "Enter maximum signal (100-2000 mV) : ", Numberl IF Numberl >= 100 AND Numberl <= 2000 THEN MaxSignal =_ Numberl

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'.*^ "4*^ i*^"'* -^^p^fsaim>p^' 101 SELECT CASE Chnl2 CASE 4 INPUT "Enter channel to moniter (0-3, 4=moniter 2 _ channels): ", Number 1 ': -,.ZIF Numberl <= 3 AND Numberl >= THEN Chnl = Numberl IF Numberl = 4 THEN INPUT "Enter first channel to moniter (0-3): ", Numberl IF Numberl <= 3 AND Numberl >= THEN Chnl = Numberl INPUT "Enter second channel to moniter (0-3, 4=disable) : ", Numberl IF Numberl <= 3 AND Numberl >= THEN Chnl2 = Numberl ELSE Chnl2 =4 IF Chnl = Chnl2 THEN Chnl2 = 4 T. END IF CASE ELSE INPUT "Enter first channel to moniter (0-3): ", Numberl IF Numberl <= 3 AND Numberl >= THEN Chnl = Numberl INPUT "Enter second channel to moniter (0-3, 4=disable) :_ " , Numberl ~ IF Numberl <= 3 AND Numberl >= THEN Chnl2 = Numberl ELSE Chnl2 =4 ~ IF Chnl = Chnl2 THEN Chnl2 = 4 ,< END SELECT ,-.. \'"^. .vf" ' GOTO Setup -^ ; ' Run Sample chosen. i X' CASE "R" CLS 2: PRINT "Press Any Key to Start Run..."; AnyKey = INPUT$(1): CLS 2 ' PRINT "Press to Stop Run..." Flag = 0: Ch = 5: Md = 3: BasAdr = 800 DatMax = 0: DatMin = ". CALL DASCONl(Md, Ch, Dio(O), Dio(l), BasAdr) '• , FOR Counter = TO RunLength AnyKey = INKEY$: IF AnyKey = CHR$(27) THEN EXIT FOR Md = 6 DO: CALL DASCONl(Md, Ch, Dio(O), Dio(l), BasAdr) LOOP WHILE Dio(8) = Dat (Counter) = INT (Dio (Chnl) * .5) IF Dat (Counter) > 2000 THEN PLAY "L32EC": Dat (Counter) = 2000: Flag =1 ~ IF Dat (Counter) < -2000 THEN PLAY "L32EC": Dat (Counter) = -2000: Flag =1 ~ IF Dat (Counter) > Dat (DatMax) THEN DatMax = Counter IF Dat (Counter) < Dat (DatMin) THEN DatMin = Counter IF Counter > THEN LINE ((Counter -1), Dat (Counter -_ 1 ) ) ( Counter , Dat ( Counter ) ) LOCATE 25, 1 PRINT USING "Chnl # ##.## ml"; Chnl; Counter * FlowRate; PRINT USING ", #### mV"; Dat (Counter) ; IF Chnl2 <> 4 THEN Dat 2 (Counter) = INT(Dio(Chnl2) * .5) IF Dat2 (Counter) > 2000 THEN PLAY "L32EC": Dat2 (Counter) = 2000: Flag = l ^, ~

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"T*"'^ IF Dat2 (Counter) < -2000 THEN PLAY "L32EC": Dat2 (Counter) = -2000: Flag = 1 IF Dat2 (Counter) > Dat2 (Dat2Max) THEN Dat2Max = Counter IF Dat 2 (Counter) < Dat2 (Dat2Min) THEN Dat2Min = Counter IF Counter > THEN LINE ((Counter -1), Dat 2 (Counter Dat2 (Counter) ) , 15 ~ Chnl # ##.## ml"; Chnl2; Counter * #### mV"; Dat2 (Counter) 1) ) -(Counter, PRINT USING " FlowRate; PRINT USING ", END IF NEXT Counter RunEnd = Counter 1: Md = 4 CALL DASCONl(Md, Ch, Dio(O), Dio(l) , BasAdr) CLS 2: PRINT "Data Run Has Ended"; IF Flag = 1 THEN PLAY "L32ECEC": CLS 2 PRINT "A Portion of This Run Was Off -Scale." PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1): CLS 2 ; T END IF IF Chnl2 <> 4 THEN CLS 2: PRINT USING "Saving Data From Channel # ..."; Chnl2 Ext$ = ".SEC": GOSUB GetName Dat2(2401) = FlowRate * 6000: Dat2(2402) = RunEnd Dat2(2403) = DatMax: Dat (2404) = Dat2Min CALL QBSave(FileSpec, SEG Dat2(0), 4810) CLS 2: PRINT USING "Data File Saved as &.SEC"; FileName PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1) END IF ' " • CLS 2: Ext$ = Chnl PRINT USING "Saving Data From Channel # ".SEC": GOSUB GetName Dat(2401) = FlowRate * 6000: Dat(2402) = RunEnd Dat (2403) = DatMax: Dat (24 04) = DatMin CALL QBSave(FileSpec, SEG Dat(O), 4810) CLS 2: PRINT USING "Data File Saved as &.SEC"; PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1): Number 1 = .1 * Dat (DatMax) YYl = Dat (DatMin) Numberl: YY2 = Dat (DatMax) + Numberl IF YYl >= THEN YYl = -Numberl XXI = 0: XX2 = RunEnd: GOSUB ReDraw .^.^ v.' Required Dummy Selection. FileName CASE GOTO ELSE MainMenu i >*•? \ i-•D'-*.r>;V *********************************************************** • Part III. Data Analysis Routine. Analysis Menu. * *********************************************************** Analysis: PRINT PRINT " = Calculate = Standard

= Plot" PRINT " = Rescale = Exit"; = Export = Setup & Run = Restore

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103 SELECT CASE UCASE$ (INPUT$ (1) ) • Exit chosen. ... .. .^ J CASE CHR$(27) ^ . ' END .... --3;///-. ' Calculate chosen. . CASE "C" IF CalFile = '•**" THEN ' v PLAY "L32ECEC": PRINT PRINT "You Must First Recall/Create a Calibration File." PRINT "Press Any Key to Continue "; AnyKey = INPUT$(1): GOTO Analysis END IF GOSUB Cursors : CLS 2 n, . INPUT "Enter the Value of Sigma: ", Sigma PRINT : PRINT "Use Universal Calibration (Y/N)? "; AnyKey = UCASE$(INPUT$(1) ) : PRINT AnyKey IF AnyKey = "Y" THEN INPUT "Enter Kl (Standard): "; Kl INPUT "Enter Al (Standard): "; Al INPUT "Enter K2 (Sample): "; K2 INPUT "Enter A2 (Sample): "; A2 CI = (Kl / K2) ^ (1 / (A2 + 1)): C2 = (Al + 1) / (A2 + 1) ELSE CI = 0: C2 = ' ^ . ' END IF ^ ... : CLS 2: PRINT "Calculating, Please Wait..."; .-:.-.. Area = 0: Suml = 0: Sum2 = Slope = (Dat(Xl) Dat(X2)) / (XI X2) FOR Counter = XI TO X2 TData = Dat( Counter) (Dat(Xl) + Slope * (Counter -XI)) IF TData < THEN TData = Area = Area + TData Mass = Dl * EXP(-D2 * FlowRate * Counter) IF CI THEN Mass = CI * Mass " C2 Suml = Suml + (TData / Mass) Sum2 = Sum2 + (TData * Mass) NEXT Counter Mp = Dl * EXP(-D2 * FlowRate * Peak) IF CI THEN Mp = CI * Mp " C2 Number = (D2 * Sigma) " 2 Mn = EXP (Number / 2) * Area / Suml Mw = EXP (Number / -2) * Sum2 / Area: MwMn = Mw / Mn VIEW PRINT 5 TO 10 LOCATE 5, 5: PRINT USING " Mp = ########"; Mp; LOCATE 6, 5: PRINT USING " Mw = ########"; Mw; LOCATE 7, 5: PRINT USING " Mn = ########"; Mn; LOCATE 8, 5: PRINT USING "Mw/Mn = #.##"; MwMn; LOCATE 9, 5: PRINT USING " Area = ########"; Area; VIEW PRINT 24 TO 25 ' Save as Standard chosen. f CASE "D" '' GOSUB Cursors IF X2 XI > 600 THEN CLS 2: PLAY "L32ECEC": PRINT "Error Region too Large." i r -If ' ./ i"

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w 7'imTT^JVr'*rf^ri0^^^' PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1): GOSUB ReDraw: GOTO Analysis END IF CLS 2: DO: INPUT "Enter Mp: "; Mp: LOOP WHILE Mp <= DO: INPUT "Enter Mw/Mn: "; MwMn , . . ^ ., LOOP WHILE MwMn <= OR MwMn > 5 PRINT "Saving Standard File...": Ext$ = ".STD" GOSUB GetName Slope = (Dat(Xl) Dat(X2)) / (XI X2) FOR Counter = XI TO X2 TData = Dat (Counter) (Dat(Xl) + Slope * (Counter -XI)) IF TData < THEN TData = Numberl = Counter XI: SData (Number 1) = TData NEXT Counter SData (601) = FlowRate * 6000: SData (604) = MwMn * 100 SData (602) = (Mp / 30000) .5: SData (603) = Mp MOD 30000 SData (605) = Peak: SData (606) = XI: SData (607) = X2 CALL QBSave(FileSpec, SEG SData(O), 1216) CLS 2 PRINT USING "Standard File Saved as &&."; FileName; Ext$ PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1) .. CASE "E" GOSUB Cursors: CLS 2: PRINT "Saving as ASCII File..." Slope = (Dat(Xl) Dat(X2)) / (XI X2) : N = FOR Counter = XI TO X2 TData = Dat (Counter) (Dat (XI) + Slope * (Counter -XI)) IF TData > N THEN N = TData NEXT Counter ^^ .^^ Ext$ = ".MPT": GOSUB GetName ON ERROR GOTO FlagError: OPEN FileSpec FOR OUTPUT AS #1 FOR Counter = XI TO X2 TData = Dat(Counter) (Dat(Xl) + Slope * (Counter XI)) IF TData < THEN TData = TData = (TData / N) * 1000 WRITE #1, Counter * FlowRate, TData NEXT Counter ON ERROR GOTO 0: CLOSE #1 ^ .u^ CLS 2: PRINT USING "File Saved as &&."; FileName; Ext$ PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1) " -.-^ . ' Plot chosen. = , CASE "P" * ' .'-^ : -•%*', • ^"-1 .-' , , { -i f' ^: CLS 2: PRINT "Plotting, Please Wait..."; CALL ScrnDump ("",1,0) . • Restore chosen. '^ ' / " t ^ f ^> CASE "T" Numberl = .1 * Dat(DatMax) : YY2 = Dat(DatMax) + Numberl YYl = Dat(DatMin) Numberl: IF YYl >= THEN YYl = -Numberl XXI = 0: XX2 = RunEnd: GOSUB ReDraw V ' Setup & Run chosen. CASE "S" "': -. GOTO Setup ,^ -• Rescale chosen.

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.l|H!IJ||il,*'"' CASE "R" CLS 2 PRINT " = Type in Values = Use Arrow Keys = Exit"; SELECT CASE UCASE$ ( INPUT$ ( 1 ) ) CASE "T" CLS 2 PRINT USING "Current X-min = ##.## ml "; XXI * FlowRate INPUT "Enter New Value: ", Number XI = Number / FlowRate PRINT USING "Current X-max = ##.## ml"; XX2 * FlowRate INPUT "Enter New Value: ", Number X2 = Number / FlowRate PRINT USING "Current Y-min = #### mV"; YYl INPUT "Enter New Value: ", Yl PRINT USING "Current Y-max = #### mV"; YY2 INPUT "Enter New Value: ", Y2 CASE "R" /' ' ' -':"'Vv^'i'' ' GOSUB Cursors . : -' . ' ' / / CASE ELSE V -^i ' '"^Sv:. GOTO Analysis END SELECT IF XI = X2 OR Yl = Y2 THEN PLAY "L32ECEC": CLS 2: PRINT "Error in Rescaling" PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1): GOTO Analysis END IF IF Yl > 2200 THEN Yl = 2200: IF Y2 < -2200 THEN Y2 = -2200 XXI = XI: XX2 = X2: YYl = Yl: YY2 = Y2 : GOSUB ReDraw • Required Dummy selection. CASE ELSE iii" «•**> r-' f*"1.>r GOTO Analysis ; . -^ * ' ' I ' •'' 1 \ ?^ i ? END SELECT ^. . ^ l^^,' ,; IL/ ^.^^ Ui i]:;. GOTO Analysis " *********************************************************** ' Part IV. Subroutines. * *********************************************************** GetName: '" DO INPUT "Enter File Name Using 8 Characters or Less: ",_ FileName LOOP WHILE INSTR (FileName, ".") OR INSTR( FileName, ":") IF FileName = "" THEN FileName = "TEMP" FileName = UCASE$ (FileName) FileSpec = "B:" + FileName + Ext$ :>y^:. Numberl = FCount% (FileSpec) IF DOS Error THEN CLS 2: PLAY "L32ECEC": PRINT "Error in Reading Data Disk." PRINT "Check Disk Drive B: and Press Any Key to_ Continue..."; AnyKey = INPUT$(1): GOTO GetName END IF , §: •::»•

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106 _ , :;,; VJ-/•:; IF Numberl > THEN IF FileName = "TEMP" THEN KILL FileSpec: RETURN PLAY "L32ECEC": PRINT PRINT USING "File && Already Exhists."; FileName; Ext$ PRINT "Overwrite it (Y/N)? "; AnyKey = UCASE$(INPUT$(1) ) : PRINT AnyKey; IF AnyKey = "Y" THEN KILL FileSpec ELSE CLS 2: GOTO GetName END IF RETURN **w' ^. r* i f'l ^i^^ Vtf ^-^* ReDraw: ; = '.%^ =. CLS 0: SCREEN 2: VIEW PRINT 1 TO 2 LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition" LOCATE 2, 34: PRINT USING "File: &"; FileName; VIEW (20, 20)-(620, 172), , 7 WINDOW (XXI, YY1)-(XX2, YY2) VIEW PRINT 23 TO 23 SELECT CASE (XX2 XXI) * FlowRate CASE IS > 160 . // ; Number = 40 / FlowRate ^v CASE IS > 80 • .' Number = 20 / FlowRate '^ CASE IS > 40 Number = 10 / FlowRate CASE IS > 20 Number = 5 / FlowRate CASE IS > 10 !;• ; . ; Number = 2 / FlowRate ^ -. -. «... CASE ELSE Number = 1 / FlowRate END SELECT N = YYl * 5 / 6: IF N >= THEN N = -.05 * YY2 FOR Counter = TO XX2 STEP Number . IF Counter >= XXI THEN LINE (Counter, YYl) -(Counter, N) Numberl = ((Counter XXI) / ( (XX2 XXI) * 8) * 600) + 2 LOCATE 23, Numberl: PRINT USING "##"; Counter * FlowRate; END IF NEXT Counter LOCATE 23, 5: PRINT "ml"; psET (XXI, Dat(xxi)) : ^, ; r FOR Counter = (XXI + 1) TO XX2 a. > LINE -(Counter, Dat(Counter) ) NEXT Counter ,• . ; VIEW PRINT 24 TO 25 RETURN : . r^ V: Cursors: ^ ^ ' ,• CLS 2 PRINT "Use Arrow Keys to Position Cursors and Press ." XI = XXI: X2 = XX2: Yl = YYl: Y2 = YY2 Numberl = 128: Number2 = 1: YYY = .05 * (YY2 YYl) DO: LINE (XI, Dat(Xl) YYY) -(XI, Dat(Xl) + YYY) LINE (X2, Dat(X2) YYY)-(X2, Dat(X2) + YYY) LOCATE 25, 1 -

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3L07 ., ,;-^, : -,.,;v PRINT USING "Left: ##.## ml, #### mV" ; XI * FlowRate; Dat(Xl) ; PRINT USING •• Right: ##.## ml, #### mV"; X2 * FlowRate; Dat(X2); ~ DO: AnyKey = INKEY$: LOOP UNTIL LEN(AnyKey) = 2 SELECT CASE ASC (MID$ (AnyKey , 2)) CASE 80 IF Numberl > 1 THEN Numberl = Numberl / 2 CASE 72 IF Numberl < 512 THEN Numberl = Numberl * 2 CASE 75 IF Number 2 = 1 AND XI >= Numberl THEN LINE (XI, Dat(Xl) YYY)-(X1, Dat(Xl) + YYY) , FOR N = XI 3 TO XI + 2 IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N + D) .T----' : -NEXT N XI = XI Numberl ' : END IF IF Number2 = 2 AND X2 > Numberl AND X2 Numberl > XI THEN LINE (X2, Dat(X2) YYY)-(X2, Dat(X2) + YYY), FOR N = X2 3 TO X2 + 2 IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N + 1)) NEXT N , • X2 = X2 Numberl END IF -^ "' CASE 77 IF Number2 = 1 AND XI < XX2 Numberl AND XI + Numberl < X2 THEN LINE (XI, Dat(Xl) YYY)-(X1, Dat(Xl) + YYY), FOR N = XI 3 TO XI + 2 IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N + 1)) NEXT N XI = XI + Numberl ^v'; < v; END IF IF Number2 = 2 AND X2 <= XX2 Numberl THEN LINE (X2, Dat(X2) YYY)-(X2, Dat(X2) + YYY), FOR N = X2 3 TO X2 + 2 IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N + 1)) NEXT N . — ^ X2 = X2 + Numberl ^ , . « , " END IF ' " * '^ ! 1i ? . CASE 71 ' ' " ' '' * ^ IF Number2 = 1 THEN Number 2 = 2 ELSE Number2 = 1 CASE 79 EXIT DO -, . ^ . CASE ELSE ' END SELECT LOOP LINE (XI, Dat(Xl) YYY)-(X1, Dat(Xl) + YYY), FOR N = XI 3 TO XI + 2 ^'t • . .' % !;^" ,

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108 IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N NEXT N -''.^^ LINE (X2, Dat(X2) YYY)-(X2, Dat(X2) + YYY) , FOR N = X2 3 TO X2 + 2 IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N + D) NEXT N Peak = XI: Valley = XI FOR Counter = XI + 1 TO X2 IF Dat (Counter) > Dat(Peak) THEN Peak = Counter IF Dat (Counter) < Dat (Valley) THEN Valley = Counter NEXT Counter Numberl = .1 * Dat (Peak): Y2 = Dat(Peak) + Numberl Yl = Dat (Valley) Numberl: IF Yl >= THEN Yl = -Numberl RETURN : : ,i„;-i FlagError: CLS 2 :-..••'^-'^ PLAY "L32ECEC": PRINT "Error in Saving File, Disk May be Full." PRINT "Press Any Key to Continue "; AnyKey = INPUT$(1) v:; ^-f RESUME Setup \SUB CalPlot (M, B, y(), X(), Stand$(), Ans%) *********************************************************** ' CalPlot is a compiled subroutine that plots the graph * ' graph of a linear function with automatic selection of * • X and y ranges. * *********************************************************** CLS 0: SCREEN 2 WINDOW SCREEN (0, .5) -(80, 25) LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition" LOCATE 2, 25: PRINT " Calibration" YMIN = y(i) FOR N = 1 TO Ans% IF y(N) < YMIN THEN YMIN = y(N) NEXT N YMIN = INT(YMIN .5): XMIN = X(l) FOR N = 1 TO Ans% IF X(N) < XMIN THEN XMIN = X(N) NEXT N i XMIN = INT (XMIN . 5) ,f \-^ ^ : ; ^, Repeat: Yint = M * XMIN + B IF Yint < YMIN THEN YMIN = INT(Yint .5) YMAX = INT(Yint + 1) ,. FOR N = 1 TO Ans% IF YMAX < y(N) THEN YMAX = INT(y(N) + 1) NEXT N Xint = (YMIN B) / M IF Xint < XMIN THEN XMIN = INT (Xint .5): GOTO Repeat XMAX = INT(Xint + 1) FOR N = 1 TO Ans% ->-• ,« ^'' r 5 * V,;^' ' : \ . •:.:• JV ,<• ..

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IF XMAX < X(N) THEN XMAX = INT(X(N) + 1) " / ^ ^ NEXT N LINE (9, 3) -(77, 20) , , B Ydelta = YMAX YMIN: Yscale = 17 / Ydelta IF Ydelta >= 10 THEN Ystep = 2 ELSE Ystep = 1 IF Ydelta >= 20 THEN Ystep = 4 FOR N = TO Ydelta STEP Ystep . . YY = 20 N * Yscale: LINE (8, YY)-(9, YY) LOCATE INT(YY + .5), 6: PRINT USING "##"; YMIN + N NEXT N Xdelta = XMAX XMIN: Xscale = 68 / Xdelta IF Xdelta >= 10 THEN Xstep = 2 ELSE Xstep =1 IF Xdelta >= 20 THEN Xstep = 4 FOR N = TO Xdelta STEP Xstep XX = 9 + N * Xscale: LINE (XX, 20) -(XX, 21) LOCATE 22, INT(XX): PRINT USING "##"; XMIN + N; NEXT N YYscale = 20 (Yint YMIN) * Yscale XXscale = 9 + (Xint XMIN) * Xscale LINE (9, YYscale) -(XXscale, 20) 4, -; LOCATE 23, 35: PRINT "Volume (ml)" ;! ' ' ' . V LOCATE 12, 2: PRINT "InM" ! : . ;^ ' ; FOR N = 1 TO Ans% IX = 9 + (X(N) XMIN) * Xscale lY = 20 (y(N) YMIN) * Yscale CIRCLE (IX, lY) , .5 LOCATE INT(IY 1), INT(IX + 4): PRINT UCASE$ (Stand$ (N) ) NEXT N END SUB ,. . -FUNCTION SelectFile% (Ext$) It********************************************************* SelectFile is a compiled funtion that returns the * number of files selected from a directory menu of * B:\*.Ext, where Ext is passed to SelectFile by the * variable Ext$. * The names of the files are passed to the main module * by the shared array Stand$ ( ) . * *****************************************it*******i,-k*i,i,-ki,i,-it DIM Item AS INTEGER, AnyKey AS STRING, Count AS INTEGER DEFINT M-N ^ ' ERASE Stand$ : CLS : SCREEN LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition" VIEW PRINT 3 TO 25 Spec$ = "B:\*" + Ext$: Count = FCount%(Spec$) IF Count = THEN PLAY "L32ECEC" PRINT USING "There Are no & Files on Data Disk."; Ext$ PRINT "Press Any Key to Continue..."; AnyKey = INPUT$(1): SelectFile% = 0: GOTO Done END IF DIM Text$(0 TO Count) -^ vi / FOR N = 1 TO Count Text$(N) = SPACE$(12)

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NEXT N Text$(0) = Spec$ CALL ReadFile(BYVAL VARPTR(Text$ (0) ) ) "^ FOR N = 1 TO Count M = INSTR(Text$(N) , ".") Text$(N) = MID$(Text$(N), 1, M 1) + SPACE$(1) NEXT N • ^ IF Ext$ = ".STD" THEN / y.,-^ LOCATE 3, 19 '^ PRINT "Select Standard Files Using the Arrow Keys." ELSE LOCATE 3, 16 PRINT "Select File to be Recalled Using the Arrow Keys." END IF LOCATE 4, 22: PRINT " = Select, = Done. " VIEW PRINT 6 TO 25 . ,;; : Item = 1: Text$ = "": N = Count '.' . ^-,. . Goes: LOCATE 6, 1 '' ,. '''^ FOR M = 1 TO N SELECT CASE INSTR(Text$, MKI$(M)) CASE IF M = Item THEN COLOR 0,7 PRINT SPACE$(1); Text$ (M) ; id ^ ' COLOR 7, 0: PRINT SPACE$(1), v:% . CASE ELSE : . IF M = Item THEN COLOR 0, 7 : . • : PRINT CHR$(26); Text$ (M) ; ^ '^^^^ / v : , COLOR 7, 0: PRINT SPACE$(1), r.. ' ' END SELECT • ,v^-^^ . >_. NEXT M -^ ,: -, ::: LOCATE CSRLIN, POS(O), -' :' PICKS: , ..^ DO: AnyKey = INKEY$: LOOP WHILE AnyKey = "" ^'''^'' ' SELECT CASE ASC (AnyKey) Hr CASE 13 ' >*-*^ a = lNSTR(Text$, MKI$(Item)) ' ; ^ IF a = THEN -"l i I C: Text$ = Text$ + MKI$(Item) ' -" ELSE ^ ' B$ = LEFT$(Text$, (a 1)) .;. {r\Q^:'p C$ = RIGHT$(Text$, (LEN{Text$) a)) " * ^ . Text$ = B$ + C$ END IF " ^ ;. .. IF Ext$ <> ".STD" AND Ext$ <> ".MPT" THEN GOTO Winners GOTO Goes CASE % . " V , r SELECT CASE ASC (MID$( AnyKey, 2)) CASE 79 ; GOTO Winners r ^v ^ .^ CASE 75 IF Item = 1 THEN Item = N ELSE Item = Item 1 GOTO Goes CASE 77 IF Item = N THEN Item = 1 ELSE Item = Item + 1 r 6 v/» r

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Ill GOTO Goes CASE 72 C^* IF N < 5 THEN GOTO PICKS ^^? Item = Item 5: IF Item <= THEN Item = N + Item GOTO Goes CASE 80 s * , IF N < 5 THEN GOTO PICKS Item = Item + 5: IF Item > N THEN Item = Item N GOTO Goes CASE ELSE -^^ ' .' ' GOTO PICKS END SELECT f^ M i >•! CASE ELSE ' '.. "^ '"^ ;. '-;"-!,>„ GOTO PICKS END SELECT Winners: M = 1 • ; ; FOR a = 1 TO N IF INSTR(Text$, MKI$(a)) THEN Stand$(M) = RTRIM$ (Text$ (a) ) M = M + 1 . . r ^ IF M = 11 THEN EXIT FOR NEXT a SelectFile% = M 1: VIEW PRINT 3 TO 25: CLS 2 Done: END FUNCTION ' J.'c>v

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..'.' f . .5".' V" BIOGRAPHICAL SKETCH When James Christopher Matayabas, Jr. — Chris to his family and friends — was born on June 23, 1961, his family lived in Frankfurt, West Germany, where his father was stationed while serving in the United States Air Force. After his father retired in 1974, his family settled in Swannanoa, North Carolina. From 1975 to 1979, Chris attended Charles D. Owen High School, where he was active in athletics and student organizations. In June, 1979, he graduated with honors. In August, 1979, Chris entered the University of North Carolina at Asheville (UNC-A) . He began playing volleyball for the USVBA-sponsored Asheville Volleyball Club and working as a student assistant for the Mossbauer Effect Data Center. Chris participated in organoantimony research under the guidance of Dr. Leo A. Bares. In the summer of 1982, Chris travelled to the Netherlands, where he worked with organoantimony complexes under the supervision of Dr. Harry K. Meinema of the Organisch Chemisch Universitaat, TNO. Having been self-supporting since 1979, Chris began fulltime employment and attended school part-time in 1983. He graduated from UNC-A with a Bachelor of Science degree with a major in chemistry in May, 1985, while teaching at Griffin School. . 112 --'-^[

PAGE 120

113 /,:,'--.• 5t--,-> On July 27, 1985, Chris was happily married to Deborah W. Weeks, mother of Joseph Johnson, age 6. In August, 1985, Chris and his new family moved to Gainesville, Florida, where Chris began graduate school at the University of Florida. He was awarded the "First Year Graduate Student In Organic Chemistry With the Highest Grade Point Average" and invited into the Phi Kappa Phi Honor Society in August, 1986. Chris chose Dr. Kenneth B. Wagener to be his research director and began research in polymer chemistry. ... v j In December, 1987, Chris was awarded the degree of Master of Science, and he presented his thesis as a finalist in the Sherwin-Williams Student Award in Applied Polymer Science competition at the Fall, 1988, National American Chemical Society Meeting. Chris continued his graduate work, pursuing the degree of Doctor of Philosophy. In October, 1990, while finishing his dissertation, he accepted employment with Eastman Chemical Company located in Kingsport, Tennessee. iv:-" y*vi% ' f. r-*"

PAGE 121

I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. Vjj^i^ tl n Kenneth B. Wagener, Chairman Associate Professor of Chemistry I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. William M. Jones' Distinguished Service Pi"ofessor of ; , ' Chemistry I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree jzi^ Doctor of Philo§£^hy. Russell S. Drago Graduate Research Professor of Chemistry I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of Philosophy. 1 ? ;;> Jol;^ A. Zoltewicz ^ Professor of Chemistry I certify that I have read this study and that in my opinion it conforms to acceptable standards of scholarly presentation and is fully adequate, in scope and quality, as a dissertation for the degree of Doctor of PhjJrOsophy. Eugene P. kSoldberg Professor of Materials Science Engineering and

PAGE 122

This dissertation was submitted to the Graduate Faculty of the Department of Chemistry in the College of Liberal Arts and Sciences and to the Graduate School and was accepted as partial fulfillment of the requirements for the degree of Doctor of Philosophy. . ,^ May 1991 Dean, Graduate School ./if^v ,; :.».;: , ' ' \ 1 i .*< j -rr ij Jr .y. M \t j t'< •.;!<': "i^',

PAGE 123

'M i/] ^\^'-UNIVERSITY OF FLORIDA 3 1262 08556 9985 -•;?fif-. ,,...(-


SYNTHESIS AND CHARACTERIZATION OF REGULAR
SEGMENTED COPOLYMERS OF POLY(PIVALOLACTONE)
AND POLY(OXYETHYLENE)
BY
JAMES CHRISTOPHER MATAYABAS, JR.
A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY
UNIVERSITY OF FLORIDA
1991

To my wife, Deborah, and son, Joseph Johnson, for their
patience, understanding, support, and, most importantly,
their love.

ACKNOWLEDGMENTS
Support for this study was provided by the Army
Research Office. The preparation procedures and samples of
2-benzoxyethanol and 2-(dimethylthexylsiloxy)ethanol were
donated by Dr. Mattson of the University of South Florida.
Pivalolactone was donated by Dr. H. K. Hall of the Univer¬
sity of Arizona. Narrow molecular weight distribution
poly(oxyethylene) glycol, PEG(1000), was donated by Dr. S.
K. Verma of Union Carbide.
I thank my supervisory committee for their contribution
to my education, with special thanks to Dr. William M.
Jones.
I thank R. W. Moshier and R. Stroschein of the Univer¬
sity of Florida Glass Shop for their excellent craftsman¬
ship. I thank Jason Portmess for his assistance in the
laboratory.
I am proud to have been a member of the University of
Florida Center for Macromolecular Science and Engineering,
more commonly known as the Polymer Floor. Special thanks go
to the Polymer Floor secretaries, Loraine Williams and Pat
Hargraves.
Special thanks go to Dr. Kenneth B. Wagener for the en¬
couragement and guidance he has given me in his warm and
friendly manner.
iii

TABLE OF CONTENTS
ACKNOWLEDGMENTS iii
ABSTRACT vi
INTRODUCTION 1
Segmented Copolymers 1
Microphase Separation 3
Poly(pivalolactone) 5
Thermoplastic Elastomers with a
Poly(pivalolactone) Hard Segment 8
Objectives of This Dissertation 13
EFFECT OF HARD-SEGMENT LENGTH
ON MICROPHASE SEPARATION 15
Introduction 15
Materials 16
Synthesis 16
Determination of Molecular Weight 17
Determination of Intrinsic Viscosity 20
Determination of Mark-Houwink Parameters ... 20
Viscosity Measurements in Other Solvents ... 23
Analysis of Microphase Separation 23
Analysis of the Soft Phase 25
Soft-Segment Segregation 28
Determination of the Hard-Phase Composition . 30
Chapter Summary 34
SYNTHESIS OF DEFECT-FREE TELECHELOMERS 35
Introduction 35
Siloxy-Protected Initiator 35
Synthesis 36
Polymerization 36
Hydroxy Acid Initiators 42
Introduction 42
Initial Attempts 43
Synthesis of Defect-Free Telechelomers 45
Formation of Dianionic Initiator 45
Dual Anionic Polymerization 49
Sequential Addition Polymerization 52
Control of the Soft-Segment Length 52
Control of the Hard-Segment Length 57
Analysis of Microphase Separation 59
Chapter Summary 62
iv

STEP POLYMERIZATION OF TELECHELOMERS
63
Introduction 63
Model Study 65
Melt Esterification of Telechelomers 69
Chapter Summary 72
EXPERIMENTAL 75
Instrumentation 75
SEC Programs 79
General Description 79
Calibration 79
Sample Analysis 81
Chemicals 81
Syntheses 83
Synthesis of 7 83
Synthesis of 8 84
Synthesis of (PVL)m-(OE)n-(PVL)m 85
Synthesis of 10 86
Synthesis of 11 86
Synthesis of 12 87
Synthesis of 13 87
Synthesis of 14 88
Synthesis of 16 88
General Procedure for
Dual-Anionic Polymerization 89
General Procedure for
Sequential Addition Polymerization ... 90
General Procedure for
Alanine-Mediated Step Polymerization . . 91
REFERENCES 92
APPENDIX 96
BIOGRAPHICAL SKETCH 112
v

Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Doctor of Philosophy
SYNTHESIS AND CHARACTERIZATION OF REGULAR
SEGMENTED COPOLYMERS OF POLY(PIVALOLACTONE)
AND POLY(OXYETHYLENE)
BY
JAMES CHRISTOPHER MATAYABAS, JR.
May 1991
Chairman: Kenneth B. Wagener
Major Department: Chemistry
Microphase separation in a series of triblock poly-
(pivalol act one -block-oxvethv lene-block-pi va lo lactone)
oligomers, represented by (PVL^-iOE) 24“(PVL)m, where m = 5,
7, 9, 12, 16, and 24, was investigated by differential
scanning calorimetry. With the poly(pivalolactone) hard-
segment length maintained at 24 repeat units, a very
distinct transition from phase mixed to essentially complete
microphase separation occurs when m is increased from 9 to
12. Complete microphase separation occurs for m = 16.
Defect-free poly(oxyethylene-block-pivalolactone)
telechelomers, represented by (OE)34“(PVL)m, where m = 5,
12, and 16, were synthesized by sequential anionic ring¬
opening polymerization of ethylene oxide and pivalolactone
with hydroxypivalic acid. These telechelomers exhibited
excellent microphase separation, allowing both the hard and
vi

soft segments to crystallize. Essentially complete micro¬
phase separation occurs for m = 12 and 16, and the sample
with m = 5 showed some microphase mixing in the hard phase.
Step polymerization of the (OE)34-(PVL)m telechelomers
was achieved by alanine-mediated melt esterification with a
titanium tetrabutoxide added in catalytic amounts, producing
low molecular weight segmented copolymers, represented by
[(OE)34-(PVL)m]p• Melt esterification of the sample with m
= 16 produced the pentamer, [(OE)34-(PVL)16]5, with Mn =
16,000 g/mole. Alanine-mediated step polymerization was
investigated in a model study involving a-hydroxypoly-
(pivalolactone) telechelomers; however, only dimers were
produced.

INTRODUCTION
Segmented Copolymers
Block copolymers can be envisioned as polymers composed
of two or more homopolymers joined at the ends. If homo¬
polymer A and homopolymer B are linked together by a
chemical bond, the resulting structure is a diblock copoly¬
mer, A-B:
aaaaa-bbbbb
where "a" represents the repeat unit of homopolymer A, and
"b" represents the repeat unit of homopolymer B. The
addition of a third block produces a triblock copolymer,
either A-B-A or B-A-B:
aaaaa-bbbbb-aaaaa or bbbbb-aaaaa-bbbbb
The coupling of four or more blocks together forms a
segmented copolymer [A-B]x:
[aaaaa-bbbbb]x
Block and segmented copolymers are of great interest
due to the unusual properties that may result, and McGrath1
has edited an excellent overview of block and segmented
copolymers. While properties that are dependent upon the
chemical nature of the segments—for example, chemical
resistance, stability, and electrical properties—are
generally unaffected, the block architecture has a strong
influence on the mechanical properties of the copolymer—for
1

2
example, elasticity and toughness. McGrath points out that
the interesting characteristic of segmented copolymers is
the strong repulsion between unlike segments that causes
like segments to segregate into two-phase physical networks.
There are a number of segmented copolymer systems which are
one phase at temperatures well above the melt but exhibit
phase separation upon cooling, resulting in a wide variety
of useful materials ranging from impact-resistant polymers
to elastomers.
Thermoplastic elastomers, which combine thermoplas¬
ticity with rubber behavior, have received the greatest
attention. Schollenberger and Scott2 first discovered
poly(urethane ether) thermoplastic elastomers in 1958, and
poly(urethane ethers) remain active subjects of investiga¬
tion.3"8 Poly(urethane ethers) typically are synthesized by
step copolymerization of an aryldiisocyanate with an
alkyldiol in the presence of a poly(ether) glycol. Poly¬
fester ether) thermoplastic elastomers, which appeared more
recently, are synthesized by analogous polyesterification
reactions of an aryldiester—or acid derivative—with an
akyldiol and poly(ether) glycol.9"15 Since the development
of living anionic chain polymerization, block copolymers can
be synthesized by the sequential addition of two or more
monomers; however, this technique is only practical for the
synthesis of diblock and triblock copolymers. Prud'homme16
used this technique to synthesize poly (styrene-block-
isoprene) copolymers for a study of microphase separation.

3
Recently, these general techniques have been combined to
synthesize a variety of block, segmented, and graft copoly¬
mers, and this is the topic of recent and future symposia.17
Microphase Separation
In general, multiphase thermoplastic elastomers contain
a soft segment and an incompatible hard segment. The soft
segments segregate to form an amorphous or semicrystalline
soft phase, and the hard segments segregate to form a
crystalline hard phase, which acts as a thermally labile
physical crosslink. These segments are chemically bonded,
and even complete segregation cannot lead to macroscopic
phase separation as is found in homopolymer blends.
Instead, microphase separation occurs where there is
sufficient incompatibility between segments.
The simplified two-dimensional drawing of the micro¬
phase separation of the hard and soft phases of an oriented
segmented copolymer given in Figure 1 offers a pictorial
representation of microphase separation. In reality,
monomer concentrations vary smoothly over the entire
microphase structure,18'19 in contrast to the abrupt changes
in concentration associated with a clearly defined interface
depicted in Figure 1.
Differential scanning calorimetry (DSC) has proven
useful in the study or microphase separation, demonstrating
that phase separation usually is incomplete.3”7 The degree
of microphase mixing in multiphase copolymers is of great
concern since it reduces the effectiveness of the physical

Soft Segment Rich Hard Segment Rich
Soft Phase Hard Phase
Figure 1. Representation of the Microphase
Separation in an Oriented Segmented Copolymer.

5
crosslink and, therefore, adversely affects the properties
of the copolymer—such as immediate elastic recovery, stress
decay, and compression set (each indicating the ability of
the polymer to return to its original condition after a
stress has been applied to it).
Factors known to enhance microphase separation include
a narrow molecular weight distribution,3»12'13'20 a suffi¬
cient hard-segment length to permit crystallization,3»4»20
and a sufficient soft-segment length.21 Wolfe9"11 carried
out extensive studies of structure/property relationships
for poly(ester ether) thermoplastic elastomers, and he found
that these materials ranged from impact resistant plastics
to elastomers, depending upon the nature and length of the
poly(ester) hard segment and depending upon the poly(ether)
soft-segment length.
Polv(pivalolactone)
Pivalolactone, 2,2-dimethyl-/3-propiolactone, reacts at
either of two sites in the molecule. Yamashita and co¬
workers22'23 investigated pivalolactone polymerization and
found that strong nucleophiles attack the carbonyl group
with acyl-oxygen fission, resulting in an alkoxide propagat¬
ing species; however, attempts to polymerize pivalolactone
with an alkoxide terminated poly(oxytetramethlyene) initi¬
ator produced homopoly(pivalolactone) due to an unknown
chain transfer reaction following the acyl-oxygen cleavage.
Jedlinski24 achieved polymerization of pivalolactone in
tetrahydrofuran by exposure to 18-crown-6 and potassium

6
metal in which the initial step of polymerization involved
attack at the methylene with cleavage of the 2,3-carbon-
carbon bond.
Lenz25, and Hall26, and Beaman27 investigated pivalo-
lactone polymerization and showed that the less nucleophilic
carboxylate anion is preferable in polymerizing
pivalolactone smoothly. Carboxylate salts attack pivalo-
lactone at the methylene carbon, opening the ring with acyl-
oxygen cleavage (Sjj2) to form a carboxylate propagating
species (Figure 2) . Carboxylate salts give fairly rapid
polymerization of pivalolactone in tetrahydrofuran and
acetonitrile with a linear relationship between polymer
molecular weight and percent conversion. The rate of
initiation by tetramethylammonium acetate is equal to the
rate of polymerization in acetonitrile. When tetraethyl-
ammonium pivalate is used as the initiator, polymerization
proceeds at the same rate, but the rate of initiation is
160% faster. Therefore, narrow molecular weight distribu¬
tion polymers are obtained, and the molecular weight is
controlled by the stoichiometric ratio of initiator to
monomer. Polymerization with carboxylates result in living
polymers, and no termination or chain transfer occurs.
High molecular weight poly(pivalolactone) is a highly
crystalline polymer that exists in three crystalline
modifications described by Osterhof28, and Borri29, and
Prud'homme.30 The a-form, the main product that crystal¬
lizes from the melt, has large lamellae, 120-180 Á, a

7
o o
II II
R- C- O- CH2C(CH3)2—c- cr
o
II
o
II
R-C--0-CH2C(CH3)2-C--0
J n
Figure 2. Initiation and Polymerization of
Pivalolactone by Carboxylate Initiator.

8
melting point temperature in the range 230-240°C, and a
glass transition temperature of -10°C for the amorphous
regions. The 0-form results from very slow cooling from the
melt and has a slightly lower melting point. The gamma-
form, which results from rapid cooling from the melt, melts
in the range 210-220°C, and Geil and coworkers31 showed that
lamellar single crystals have a thickness of about 70 Á.
Thermoplastic Elastomers with a
Poly(pivalolactone) Hard Segment
Poly(pivalolactone), poly(oxypivalyl), is an excellent
choice for a thermoplastic-elastomer hard segment due to its
high tendency to crystallize, solvent resistance, and narrow
molecular weight distribution. Caywood32 modified a number
of poly(alkyl acrylates) by saponifying some of the ester
groups by reaction with tetrabutylammonium hydroxide and
using the formed carboxylate salts to initiate polymeriza¬
tion of pivalolactone. Sharkey33'34 synthesized block and
graft copolymers of pivalolactone with isoprene and with
isobutylene.
Segmented poly(ester ethers) containing poly(pivalo¬
lactone) show promise as thermoplastic elastomers.
Yamashita23 synthesized poly(pivalolactone-block-oxytetra-
methylene-block-pivalolactone) triblock copolymers by
converting the potassium alkoxide anions of poly(oxytetra-
methylene) glycol to potassium carboxylate anions with
succinic anhydride, followed by pivalolactone polymeri¬
zation. Inoue and coworkers35 used aluminum porphyrin
catalysts to synthesize low molecular weight versions of

9
poly (/3-propiolactone-block-oxyethylene) copolymers having
monodisperse segments by sequential addition of 0-propio-
lactone and ethylene oxide; however, this method is only
useful for the synthesis of low molecular weight diblock
copolymers.
Wagener and Wanigatunga36-38 focused on the synthesis
of a monodisperse telechelomer (a telechelomer is a self¬
reacting monomer capable of step polymerization only) and
its step polymerization to segmented copolymer. Their
approach (Figure 3) , termed chain-propagation/step-propaga¬
tion polymerization, utilizes living anionic chain propaga¬
tion to synthesize the narrow molecular weight distribution
segments of the telechelomer sequentially. Then, step
polymerization of the telechelomer results in a segmented
copolymer, and although the overall molecular weight
distribution will be large—Mw/Mn greater than 2—within
each segmented copolymer the segments should maintain their
narrow molecular weight distributions.
Wagener and Wanigatunga36-38 utilized chain-propaga¬
tion/ step-propagation polymerization to synthesize poly-
(pivalolactone-block-oxyethylene) telechelomers (Figure 4) .
In the first step, an acetal capped anionic initiator (1)
polymerized ethylene oxide to give 2, a potassium alkoxide
of a masked poly(ether). Excess succinic anhydride quanti¬
tatively converted the alkoxide anion of 2 to a carboxylate
anion (3.) , the preferred initiating anion for polymerizing
pivalolactone smoothly. Then 3_ was used to polymerize

10
n A
r
HA)n-
m B
I-(A)n-(B)m-
h3o+
HO-I-(A)n-(B)m-COOH
step polym.
-[0-I-(A)n (B)m-CO]p-
Figure 3. Chain-Propagation/Step-Propagation
Polymerization Strategy for Initiation by a
Monofunctional Initiator.

Figure 4. Synthesis of Poly(oxyethylene-
block-pivalolactone) Telechelomer (5) and
Segmented Copolymer (6).

12
CH3-CH-0(CH2)30K+
och2ch2
1
n
o
ZA
CH3-CH-0(CH2)3-(0CH2CH-2)ir0K+
OCH2CH2
2
CH3-CH-0(CH2)3-(0CH2CH2)—coch2ch2cook+
och2ch2
CH3-CH-0(CH2)3-(0CH2CH2)—SA-(OCH2-C-CO)m-OK+
och2ch2 ch3
h3o+
ch3
HO(CH2)3(OCH2CH2)—SA-(OCH2“C-CO)m-OH
K CH3
1. 185°, alanine, 2 hrs.
2. 0.5 mm Hg, 0.5 hrs.
3. Ti(OBu)4, 185-260°C,
At atmosphere, 1.5 hrs.
4. 0.5 mm Hg, 0.5 hrs.
ch3
(CH2)3—(OCH2CH2)—SA-(0CH2-C-C0)m-0
ch3
p

13
pivalolactone, giving a masked poly(pivalolactone-block-
oxyethylene) copolymer salt (4) which was converted to
telechelomer (5) by acid hydrolysis. Telechelomer 5 was
converted to segmented copolymer (6) by melt esterification
with alanine and titanium tetrabutoxide, where the role of
alanine is unclear.
Products 5 and 6 posses narrow molecular weight
distributions for both segments, and depending on their
ratio, the copolymers can act as thermoplastic elastomers
wherein the poly (oxyethylene) segment acts as a soft phase
and the poly(pivalolactone) segment acts as a hard phase.
Wagener and Wanigatunga20 analyzed the microphase separation
in telechelomer 5 and found that considerable microphase
mixing occurs.
Objectives of This Dissertation
In order to obtain a better understanding of the
microphase separation of poly (oxvethvlene-block-pivalo-
lactone) copolymers, the microphase separation behavior of
poly (pivalolactone-block-oxvethvlene-block-pivalolactone)
oligomers is investigated as a function of the poly(pivalo¬
lactone) hard-segment length. The goal of this study is to
determine the minimum length of hard segment necessary to
achieve a high degree of microphase separation with a
constant poly(oxyethylene) soft-segment length of 24 repeat
units.

14
Previous poly(oxyethylene-block-pivalolactone) tele¬
chelomers20 exhibited considerable microphase mixing, and
this microphase mixing can be attributed in part to the
irregularity of the copolymer chain due to the initiator
fragment and the succinate link. Therefore, a defect-free
telechelomer should produce a segmented copolymer with
superior microphase separation. The major goal of this work
is the synthesis and characterization of a defect-free
poly(oxyethylene-block-pivalolactone) telechelomer.
After the telechelomers are synthesized, their step
polymerization to segmented copolymers is addressed,
including model studies utilizing homo-poly(pivalolactone)
telechelomers.

EFFECT OF HARD-SEGMENT LENGTH
ON MICROPHASE SEPARATION
Introduction
In a previous study aimed at gaining a better under¬
standing of microphase separation, Wagener and Matayabas21
utilized DSC to guantitatively investigate the microphase
separation behavior in a series of poly(pivalolactone-block-
oxvethvlene-block-pivalolactone) oligomers with the poly¬
oxyethylene) soft-segment length varying from 4 to 24
repeat units. The B-A-B triblock structure with two
poly(pivalolactone) hard segments was chosen because it is
the simplest segmented copolymer that can form a two-phase
physical network in which the hard-phase domains are
covalently linked by the soft segment. Their study showed
that, with a poly(pivalolactone) hard-segment length of 12
repeat units, a minimum of 14 oxyethylene repeat units are
required to achieve some degree of microphase separation and
essentially complete microphase separation occurs when the
poly(oxyethylene) soft-segment length is increased to 24
repeat units.
In this present study the effect of hard-segment length
on microphase separation is examined. The goal is to deter¬
mine the minimum length of hard segment necessary to achieve
a high degree of microphase separation with a constant poly-
(oxyethylene) soft-segment length of 24 repeat units.
15

16
Materials
Synthesis
A series of polv(pivalolactone-block-oxvethvlene-block-
pivalolactone) oligomers, represented by (PVL)m-(OE)24-
(PVL)m, were synthesized according to the scheme presented
in Figure 5. The poly(pivalolactone) hard-segment length
(m) varies from 5 to 24 repeat units, and the polyoxy¬
ethylene) soft-segment length was maintained constant at 24
repeat units by beginning with narrow molecular weight
distribution poly(oxyethylene) glycol.
The hydroxyl end groups of the poly(oxyethylene) glycol
were converted to carboxylic acid end groups in refluxing
toluene with excess succinic anhydride, producing a-hydroxy-
succinyl-w-hydroxysuccinyloxypoly(oxyethylene) (7). Product
7 was converted to the dicarboxylate salt (8) by reaction
with potassium metal in dry tetrahydrofuran under vacuum.
Tetrahydrofuran solutions of 8 were used to polymerize
pivalolactone under dry argon to produce the (PVL)m-(OE)24-
(PVL)m oligomers. The length of the poly(pivalolactone)
hard-segment block (m) is easily controlled by the stoichio¬
metric ratio of initiator to monomer due to the anionic
ring-opening polymerization mechanism, and (PVL)m-(OE)24-
(PVL)m with m = 5, 7, 9, 12, 16, and 24 were synthesized.
Due to the solvent resistance of the poly(pivalo¬
lactone) segments, the (PVL)m-(OE)24-(PVL)m oligomers with m
greater than 7 are insoluble in most organic solvents
including acetone, methylene chloride, chloroform,

17
acetonitrile, dimethylsulfoxide, and cold N,N-dimethylform-
amide. They are soluble in acidic solvents such as 3-
methylphenol, 4-chlorophenol, and methylene chloride with 1%
trifluoroacetic acid. The (PVL)m-(OE)24-(PVL)m oligomers
are soluble in hot N,N-dimethylformamide and precipitate
only slowly on cooling.
Determination of Molecular Weight
The molecular weight of the poly(oxyethylene) macro-
molecular initiator, 7, was determined by titration with
0.10 N potassium hydroxide in methanol, giving a number-
average molecular weight (Mn) of 1260 g/mole. This value
agreed well with the proton NMR integration of the poly(oxy¬
ethy lene) methylene singlet and the succinate methylene
singlet. The existence of a narrow molecular weight
distribution—Mw/Mn less than 1.05—was confirmed by size-
exclusion chromatography.
The proton NMR of (PVL)12“(0E)24”(PVL)12' Silanor-C
with 1% trifluoroacetic acid, is presented as Figure 6. The
average value of m is easily determined by detecting and
integrating the proton NMR signals of the 1.23 ppm methyl
singlet (a) of the main chain poly(pivalolactone) segment
and the 1.31 ppm methyl singlet of the terminal pivalo¬
lactone unit. Additional information regarding the amount
of incorporated pivalolactone is obtained from comparison of
the poly(oxyethylene) methylene singlet (c) at 3.72 ppm, the
poly(pivalolactone) methylene singlet (d) at 4.12 ppm, and
the succinate link methylene singlet (b) at 2.69 ppm.

18
H-(OCH2CH2)24-OH
2. work up
O O O
ii ii it
hoc-ch2ch2-c—(OCH2CH2)24-OC-CH2CH2
o
II
-COH
7
K, THF
o o o o
, II II II II
K'OC—CH2CH2—C—(OCH2CH2)24—OC_CH2CH2—CO*K+
8
ch3
ch3^
2m
o ch3 h3c o
+KO-(C C CH20)n-SA-(0CH2CH2)24SA-(0CH2—C-C)n—OK+
CH H C
(PVL)m-(OE)24-(PVL)m
Figure 5. Reaction Scheme for the Synthesis of
Poly(pivalolactone-block-oxvethvlene-block-pivalolactone)
Triblock Oligomers.

19
O CHj O O .0 O CHa O
*K‘0-(C™C*CH20)i2 — C*CH2CH2 — C — (OCH2CH2)24 O~C — CH2CH2-C“(OCH2-CC)i2*
ch3
c/e
V J
CH,
J
Figure 6. Proton NMR of (PVL)12“(0E)24”(pVL)12

20
Determination of Intrinsic Viscosity
Recently, Guillet39'40 showed that excellent agreement
of the intrinsic viscosity ([n]) is obtained from a single
measurement of the viscosity of polymers in the molecular
weight range 103-106 using the Solomon-Ciuta equation41:
[n] = [2 nsp - 2 ln(nr)]1/2/c (1)
where nSp represents the specific viscosity, nr represents
the relative viscosity, and c represents the concentration
of the polymer solution.
Table 1 presents the number-average molecular weights,
Mn, determined by proton NMR and the measured intrinsic
viscosities, [n], of 0.005 g/ml solutions of the (PVL)m-
(OE)24-(PVL)m oligomers in methylene chloride containing 1%
trifluoroacetic acid at 30°C, calculated by Equation 1.
Table 1. Intrinsic Viscosities ([n]) and
Number-Average Molecular Weights (Mn) of
(PVL)m-(OE)24-(PVL)m Oligomers.
m
5
7
9
12
16
24
Mn
2400
2900
3100
3900
4500
6100
[n] dl/g
0.075
0.081
0.083
0.084
0.098
0.104
Determination of Mark-Houwink Parameters
For linear polymers, a plot of ln[n] versus lnMv
produces slope = a and intercept = InK, according to the
Mark-Houwink Equation42:
ln[n] = a*lnMv + InK
(2)

21
where K and a are termed the Mark-Houwink parameters, and Mv
represents the viscosity-average molecular weight. Dondos
et al.43, showed that this relationship also holds for
linear block and random copolymers. The error resulting
from substituting Mn for Mv is small for narrow molecular
weight distribution samples,42 and from the plot of Equation
2 for the (PVL)m-(OE) 24~(PVL)ln oligomers (Figure 7), a =
0.35 and K = 0.48 ml/g.
Size-exclusion Chromatography
The validity of the calculated Mark-Houwink parameters
for the (PVL)m-(0E)24-(PVL)m oligomers was checked by size-
exclusion chromatography (SEC) analysis versus poly(styrene)
standards—see EXPERIMENTAL for the determination of the
Mark-Houwink parameters for poly(styrene). The samples were
analyzed at concentrations of 0.005 g/ml in methylene
chloride containing 1% trifluoroacetic acid. Under these
conditions, the (PVL)m-(OE)n-(PVL)m oligomers gave only weak
signals as detected by a differential refractometer. Homo¬
polymers of pivalolactone and ethylene oxide give signals
with opposite polarities in this solvent, and the copolymer
signals are weak due to the opposing polarities of the
poly(pivalolactone) and poly(oxyethylene) signals. The weak
signals were partially masked by the solvent signal, and
this prevented obtaining reliable polydispersity data.
However, the peak molecular weights, which should correspond
well with Mn for narrow molecular weight distribution
polymers, agreed well with the known composition.

[U]U|
22
Figure 7. Plot of Mark-Houwink Equation
(Equation 2) for (PVL)m-(OE)24”(pvL)m oligomers.

23
Viscosity Measurements in Other Solvents
Attempts to determine the intrinsic viscosity of the
(PVL)m-(OE)24-(PVL)m oligomers in N,N-dimethylformamide were
met with many difficulties due to formation of aggregates
and slow precipitation of the solute. For example, the
intrinsic viscosity of (PVL)9-(OE)24“(PVL)9 was determined
to be 24.5 ml/g within two hours of dissolving in hot N,N-
dimethylformamide and increased to 28.7 ml/g 24 hours later.
Plots of Equation 2 for (PVL)m-(OE)24”(pVL)m in N,N-di-
methylformamide produced a = 3.0 and K = 0.12 ml/g.
Analysis of Microphase Separation
DSC is an excellent method of detecting glass transi¬
tions and melting points.44 For a polymer containing an
amorphous soft phase and a crystalline hard phase, DSC
evaluation of microphase separation is accomplished by 1)
comparing the observed glass transition temperature of the
soft phase (Tg°bs) of the segmented copolymer with the glass
transition of the soft-segment homopolymer (TgS) and 2)
comparing the observed melting point temperature of the hard
phase (Tmot,s) with the melting point of the hard-segment
homopolymer (TmH). The strength of this process lies in its
ability to produce a complete description of the microphase
separation behavior, providing information about the soft
and hard phases.

Endothermic
24
Figure 8. Low Temperature DSC Scans of
(PVL) m- (OE) 24” (PVL) Quenched from 50°C.

25
Analysis of the Soft Phase
The low temperature DSC scans of (PVL)m-(OE)24“(PVL)m
triblock oligomers, with soft-phase glass transitions
normalized per gram of sample, are presented in Figure 8.
Each sample was quenched from 50°C in order to freeze the
soft phase into a fully amorphous state at Tgobs and to
guarantee that the thermal history of each sample is
identical.
The recorded values for Tg°bs and change in heat
capacity per gram of soft segment (deltaCp0t,s/Wg) of (PVL)m-
(OE)24”(PVL)m, reported in Table 2, show a distinct dif¬
ference in the glass behavior of the soft phase in the
samples with m greater than 9. The samples for m = 5, 7,
and 9 exhibit Tg°bs between -46 and -42°C, and the samples
for m = 12 and 16 exhibit TgObs at -60 and -61°C, respec¬
tively, indicating a marked increase in the soft-phase
purity in these samples. An analysis of the soft-phase
microphase separation of m = 24 is presented; however, Tgot)S
for m = 24 is difficult to determine due to the small weight
percent of soft phase in this sample.
Factors known to affect Tgobs include molecular weight,
end groups, percent crystallinity, thermal history, and
diluents.44 Thus, with all other factors being equal, an
increase in Tgobs is an indication of the presence of a
diluent.

26
Wood45 demonstrated that the observed glass transition
temperature of a single-phase, two-component system is the
linear weighted addition of the two individual glass
transitions:
(k-Wi + W2)Tgobs = k*Wx*Tg1 + W2 *Tg2 (3)
where W-^ and W2 represent the weight fractions of components
1 and 2, and Tg1 and Tg2 represent the glass transition
temperatures of components 1 and 2, and k is a constant.
Several researchers46-49 have attempted to assign physical
significance to the constant, k, while Wood supports
determining k by studying samples of known composition and
plotting the results according to the following rearranged
form of Equation 3:
Tg°bs = (_i/k)(TgObs _ Tgl}(Wl/W2) + Tg2 (4)
A plot of Tgobs versus (Tg°bs - Tg1)(W1/W2) produces a line
having slope = -1/k and intercept = Tg2.
Wood's equation has been shown to apply to microphase
separated segmented copolymers having a mostly crystalline
hard phase that is rich in component 2 (called the hard
segment) and a mostly amorphous soft phase that is rich in
component 1 (called the soft segment).3-5»21 Because this
is a two-component, two-phase system in which only the
amorphous soft phase participates in the glass transition,
the individual weight fractions Wj^ and W2 in Equation 3
become the weight fractions of the soft and hard segments in
the soft phase, Mss and MHS respectively:
(k-Mss + MHS)Tgobs = k-Mss-TgS + MHS-TgH
(5)

27
where TgS and TgH represent the glass transition tempera¬
tures of the ideally microphase separated soft and hard
segments, respectively.
Solving Equation 5 for Mgs produces Equation 6:
Mgg = (k-TgH - k*Tg°bS)/(Tg°bS - TgS + k*TgH - k*Tg0bS)
(6)
From Equation 6, and noting that MHS = Mss - 1, the soft-
phase composition is determined from the observed glass
transition temperature of the amorphous phase, provided that
suitable values for k, Tgs, and Tg11 are found.
Table 2. Results of Quantitative DSC Analysis
of the Soft-Phase Microphase Separation of
(PVL)m-(OE)24-(PVL)m Oligomers.
m
5
7
9
12
16
24
ws
0.50
0.45
0.38
0.29
0.25
0.18
T^obs oQ
-46
-44
-42
-60
-62
-52
deltaCpobs/Wg
J/g
0.76
0.74
0.65
0.79
0.81
0.4
Mss
0.46
0.43
0.39
0.98
1.1
0.6
SRg
—
—
—
0.95
0.98
0.5
The values of Mss, reported in Table 2, were calculated
according to Equation 6, using k = 0.24, TgH = 7°C, and Tgs
= -60°C, as determined in the previous study.21 The values
of Mgg clearly show that substantial microphase mixing
occurs for the samples for m = 5, 7, and 9. The observance
of a cold crystallization for (PVL)5-(OE)24“(PVL)5 indicates

28
that microphase separation has occurred; however, the value
of 0.46 for Mss indicates that no microphase separation has
occurred. Perhaps a value of 0.24 for k, determined for
triblocks containing 12 poly(pivalolactone) repeat units, is
inaccurate for this sample.
Based on the calculated values of Mgg, the soft phase
in the samples for m = 12 and 16 are nearly pure in soft
segment, and the value of 0.98 for Mgg of (PVL) ^2~ (0E) 24”
(PVL)i2 indicates that the soft phase contains 98% by weight
poly(oxyethylene) soft segment. The observance of a cold
crystallization and the melting of the crystalline regions
in the soft phase of (PVL)16”(0E)24”(pVL)16 clearly indicate
high soft-segment purity, and a value of 1.1 was calculated
for Mss. A value greater than unity for Mss reveals the
limitations of estimating TgS, the glass transition tempera¬
ture of the ideally microphase separated soft segment, with
the glass transition temperature of the poly(oxyethylene)
initiator 7.
Soft-Segment Segregation
Camberlin and Pascault6'7 introduced a method of
determining the soft-segment segregation (SRS), which is
defined as the weight fraction of soft segment in the soft
phase with respect to the total weight of soft segment in
the copolymer:
SRS = (deltaCpobs/Wg)/deltaCps (7)
where deltaCp°bs/Wg represents the observed change in heat
capacity per gram of soft segment in the copolymer, and

29
deltaCpS represents the change in heat capacity at the glass
transition of the soft-segment homopolymer. Camberlin and
Pascault6'7 used Equation 7 to quantitatively determine the
soft segment segregation of segmented copolymers containing
diphenylmethane di isocyanate based poly (urethane) and
poly(urea) hard segments and varying soft segments.
Brunette et al.,5 used a similar equation to quantitatively
determine the soft phase composition of segmented copolymers
containing diphenylmethane diisocyanate based poly(urethane)
hard segments and poly(oxybutadiene) soft segments.
Equation 7 does not take into account the contribution
to deltaCp°bs by the hard segments in the soft phase, and
Wagener and Matayabas50 showed that when this contribution
is considered, a slightly different equation results:
SRS = (Mss-deltaCpobs/Ws)/(Mss-deltaCpS + MHS-deltaCpH)
(8)
where deltaCpH represents the change in heat capacity at the
glass transition of the hard-segment homopolymer. If the
multiphase copolymers are very well microphase separated or
if deltaCpH is very small, then Equation 8 reduces to
Equation 7, and since the change in heat capacity for
poly (pivalolactone) is too small to be detected by DSC,
Equation 7 is valid for microphase separated poly(pivalolac-
tone-block-oxyethylene) copolymers.
The values of SRS, also in Table 2, were calculated
according to Equation 7, where deltaCps = 0.83 as previously
determined.21 A value of 0.95 for (PVL)12“(0E)24"(PVL)12

30
indicates that 95% of the poly(oxyethylene) soft segments in
this sample is located in the soft phase, leaving 5% in the
hard phase or a mixed interface. And a value of 0.98 for
(PVL)16-(OE)24“(PVL)ig indicates that essentially all of the
soft segments are located in the soft phase.
Determination of the Hard-Phase Composition
Once both Mss and SRS are known, it is a simple matter
to determine the composition of the hard phase. Assuming
that only two phases are formed, the weight fraction of the
hard segment in the hard phase (MHH) can be estimated21:
MHH = 1 - [Mss•Ws(1 - SRS)/(MSS - SRS•Ws)] (9)
And, similar to SRS, the hard-segment segregation (SRH) is
calculated by the following equation21:
srh = (mss*mhh ~ srs*ws*mhh)/(mss*wh) (10)
where Wjj represents the weight fraction of the hard segment
in the copolymer (Wfj = 1 - Ws) .
The calculated values of Mjjjj and SRjj, listed in Table
3, indicate high hard-segment purity in all of the micro¬
phase separated samples. A 0.99 value of Mjjjj for (PVL)12“
(OE)24“(PVL)12 indicates that the hard segment of this
sample contains 99% by weight poly(pivalolactone) hard
segment, and a 1.0 value of SRH for (PVL)1g-(OE)24-(PVL)16
indicates complete microphase separation.
Figure 9 presents the high temperature DSC scans of
(PVL) jjj- (OE) 24”( PVL) m, showing the hard-phase melting
endotherms (Tmobs). The values of Tmobs, listed in Table 3,
increase with increasing hard segment length m.

Endothermic
31
m = 7
m = 5
100
T T
150 200
Temperature (°C)
2S0
Figure 9. High Temperature DSC Scans of
(PVL)m-(OE)24"(pVL)m Oligomers.

32
Table 3. Results of Quantitative DSC Analysis
of the Hard-Phase Microphase Separation of
(PVL)m-(OE)24“(PVL)m Oligomers.
m
5
7
9
12
16
24
wH
0.50
0.55
0.62
0.71
0.75
0.82
mhh
—
—
—
0.98
0.99
0.9
srh
—
—
—
0.99
1.0
0.9
m ObS op
Am
142
152
172
200
201
207
m H op
Am
174
182
190
201
205
215
PH
0.73
0.76
0.76
0.99
0.94
0.94
Block copolymerization decreases the observed melting
point (Tmobs) of a crystalline segment, and Tmobs in a block
copolymer can be calculated by Equation ll52:
1/Tm°bs = 1/TmH " (R/deltaH)*lnpH (11)
where TmH represents the melting point of the hard-segment
crystalline homopolymer, deltaH represents the heat of
fusion per mole of repeat unit of the crystalline hard-
segment, and pH represents the hard-segment crystalline
sequence propagation probability. This equation has been
used to calculate Tm°bs of the poly(hexamethylene sebacate)
segment due to block copolymerization with a poly(dimethyl-
siloxane) segment.53'54 Wagener and Wanigatunga20 used
Equation 11 to calculate the upper and lower limits of the
poly(pivalolactone) hard segment in their poly(oxyethylene-
block-pivalolactone) telechelomers. The upper limit, with
pH = 1, equals TmH, and the lower limit was calculated using

33
pH = Wh> The lower limit is the Tmobs expected if no
microphase separation occurs, and the upper limit is the
Tm°kS expected for complete microphase separation. From
this range, they were able to qualitatively determine the
hard phase composition.
An interesting application of Equation 11 is obtained
by solving for pH:
pH = EXP[(1/TmH - l/Tmobs)*deltaH/R] (12)
From Equation 12, pH can be calculated, and pH should be a
very good approximation for SRH. The values of pH for the
(PVL)m-(OE)24-(PVL)in oligomers in Table 3, were calculated
from Equation 12 using a value of 3550 cal/mole of repeat
unit55 for deltaH and the TmH of homopoly(pivalolactone)
with the corresponding molecular weight, also listed in
Table 3.
The calculated values of pH show that the crystalline
hard-phase purity increases with increasing hard-segment
length for m = 5 through 12. The values between 0.73 and
0.86 for m = 5, 7, and 9, in contrast to the soft segment
data, indicate that the hard segment has partially micro¬
phase separated. For example, the 0.73 value of pH suggests
that the crystalline hard phase of (PVL)5-(OE)24-(PVL)5 is
richer in poly(pivalolactone) hard segment than the 0.50
value, from WH, that is expected if no microphase separation
occurs. The 0.99 value of pH for m = 12 is identical to the
SR|j calculated from the soft-segment data and indicates that
the crystalline hard phase of (PVL)^2"(0E)24"(pvL)12 is

34
completely microphase separated. The 0.94 value of pH for m
= 16 also indicates a high degree of crystalline hard-phase
purity; however, this value is slightly lower than the 1.0
value of SRjj. The 0.94 value of pH for m = 24 agrees well
with the 0.9 value of SRjj.
Chapter Summary
Quantitative determination of the microphase separation
in a series of (PVL)m-(OE)24“(PVL)m oligomers was achieved
by DSC analysis. The poly(oxyethylene) soft-segment length
was maintained at 24 repeat units, and the poly(pivalo-
lactone) hard-segment length (m) was varied from 5 to 24
repeat units. For shorter hard-segment lengths, the soft
phase is microphase mixed; however, the crystalline hard
phase appears to exhibit a small degree of microphase
separation. A very distinct transition from microphase
mixed to essentially complete microphase separation occurs
when m is increased from 9 to 12. Complete microphase
separation occurs for (PVL) (0E) 24” (pvij) 16 • In ea°h case,
the hard-segment is the major component, and microphase
separation occurs to a larger extent in the hard phase than
in the soft phase.

SYNTHESIS OF DEFECT-FREE TELECHELOMERS
Introduction
Poly(oxyethylene-block-pivalolactone) segmented
copolymers have promise as thermoplastic elastomers;
however, the low melting points of the existing telechelo-
mers20 indicate that substantial microphase mixing occurs.
The initiator fragment and the succinate link comprise over
6% of the total weight of the telechelomer and are probably
responsible for much of the microphase mixing. If this is
the case, a telechelomer that is free from these defects
should exhibit excellent microphase separation.
Siloxv-Protected Initiator
It is possible to eliminate, or mask, the initiator
fragment in the synthesis of poly(oxyethylene-block-pivalo-
lactone) telechelomers by duplicating the chain-propaga¬
tion/ step-propagation strategy utilizing initiators that
leave a fragment that has the same structure as the polymer
repeat unit. Polymerization of ethylene oxide with a mono-
protected ethylene glycol initiator would result in a
poly(oxyethylene) in which the initiator fragment has a
structure identical to the poly(oxyethylene) repeat unit.
The trimethylsiloxy protecting group has been shown to be
fairly stable in the anionic polymerization of 2-(trimethyl-
silyloxy)ethyl methacrylate at -78°C with some anionic
35

36
initiators56, and 2-(dimethylthexylsiloxy)ethanol was
selected to attempt polymerization of ethylene oxide.
Synthesis
2-(dimethylthexylsiloxy)ethanol (11) was synthesized by
the reaction scheme presented in Figure 10. The reaction of
dimethylthexylsilyl chloride with 2-benzoxyethanol, in N, N-
dimethylformamide in the presence of imidazole, produced 1-
benzoxy-2-(dimethylthexylsiloxy)ethane (10), isolated by
vacuum distillation. Hydrogenation of 10 with H2 and
palladium-charcoal in dry tetrahydrofuran produced 11. in 98%
purity, by gas chromatography, after vacuum distillation.
The proton NMR of 1JL (Figure 11) , in deuterated
chloroform without tetramethylsilane, has three characteris¬
tic methyl signals: the dimethyl singlet at 0.0 ppm (a, 6
hydrogens) and the thexyl group methyl singlet (b, 6
hydrogens) at 0.75 ppm and methyl doublet (c, 6 hydrogens)
at 0.8 ppm. The other signals are the tertiary-hydrogen
multiplet (d) centered at 1.51 ppm, the alcohol proton
singlet (e) at 2.04 ppm, and the glycol methylenes pair of
multiplets (f, 4 hydrogens) centered at 3.55 ppm.
Polymerization
Figure 12 presents the reactions obtained by the
polymerization of ethylene oxide with 11. The potassium
salt of JL1 (12) was formed by reaction with potassium
mirror in tetrahydrofuran, with precipitation of the
product. Ethylene oxide was vacuum transferred into the
reaction flask in a 20:1 ratio, and the reaction was stirred

37
at 5°C for 3 days. The polymer product (13.) was isolated by
evaporating the tetrahydrofuran, dissolving the residue in
water, acidifying with dilute hydrochloric acid, and
extracting with methylene chloride. Product 13 was deter¬
mined to be poly(oxyethylene) glycol by proton NMR, with Mn
= 2100 and Mw/Mn = 1.1 by SEC, calibrated with polyoxy¬
ethylene) glycol standards.
To determine whether or not the siloxane was hydro¬
lyzed, later polymerizations were guenched after 2 days with
succinic anhydride, without hydrolysis of the final product
(14) . The SEC trace of 14 produced one slightly broad
signal, with Mn = 1800 g/mole. The composition of 14 was
determined by proton NMR (Figure 13) integration of the 12-
hydrogen methyl singlet and doublet of the siloxy group at
0.8 ppm (a), the 4-hydrogen methylene singlet of the
succinate group at 2.55 ppm (b) , and the methylene singlet
of poly (oxyethy lene) at 3.55 ppm (c) . The other signals
result from the methylene at the end of the poly (oxyethy 1-
ene) chain that is linked with the succinate group (d, 4.2
ppm triplet) and the methyls attached to silicon (e, 0 ppm
singlet). Product 14 is a 4:1 mixture of the di- and mono¬
succinate poly(ether), o-hydroxysuccinyl-w-hydroxysuc-
cinyloxypoly(oxyethylene) and a-hydroxysuccinyl-w-(dimethyl-
thexylsilyloxy)poly(oxyethylene), respectively. Precipita¬
tion of concentrated methylene chloride solutions of mixture
14 with diethyl ether resulted in the isolation of a white
solid containing very little siloxane.

38
imidazole, DMF
IQ
H2, Pd/C
Si- OCH2CH2—OH
II
Figure 10. Reaction Scheme for the Synthesis
of 2-(Dimethylthexylsiloxy)ethanol, 11.

39
Figure 11. Proton NMR of
2-(Dimethylthexylsiloxy)ethanol, 11.

40
>
>
I
■ S i- OCHoCHo—OH
I
11
K. THF
I
S i-OCH2CHo—0‘K+
I
12
n / \ ,THF
HoO,
H—(OCH2CH2)n—OH 4 H02CCH2CH2C0—(0CH2CH2)n-02CCH2CH2C02H
I
1 H02CCH2CH2C0-(0CH2CH2)n-0-Si¬
ll
Figure 12. Reactions Obtained From the Polymerization of
Ethylene Oxide by 2-(Dimethylthexylsiloxy)ethanol, 11.

41
d
i » 1 i ■ jt i—r
4
;
ho2cch2ch2co—(OCH2CH2)_- o2cch2ch2co2h
V V/
b c,d b
I
H02CCH2CH2C0—(OCH2CH2)n— O- S i-
V
e a
a
4 ^
*4 ^ . .Jl— ,
' | ■ 1 ■ ' I 1 1 I 1 ■' 1~"r~T~' l-'T-,-, r r-i—i -t-i T r r .-r-, I ■■■
3 2 10 ppm
Figure 13. Proton NMR of 14.

42
The siloxy protecting group is not stable under the
harsh conditions of the anionic polymerizations at 5°C, and
this is not a viable route to poly(oxvethvlene-block-pivalo-
lactone) telechelomers. It may prove to be a route to high
molecular weight poly(oxyethylene) glycols with fairly
narrow molecular weight distributions; however, this avenue
was not pursued.
Hvdroxv Acid Initiators
Introduction
The formation of a diblock species from ethylene oxide
and pivalolactone without the use of succinic anhydride to
convert the alkoxide to a carboxylate requires that the
carboxylic acid and hydroxyl functionalities be already
present in the initiator. Initiation by a hydroxy acid, a
difunctional initiator, to form a diblock telechelomer
requires polymerization from both ends of the initiator in
an inside out fashion much like that used to form the
triblock structures. This chain-propagation/step-propaga-
tion polymerization strategy for initiation by a difunction¬
al initiator, presented in Figure 14, is a novel utilization
of a difunctional initiator.
Since hydroxy acids are difunctional initiators, it may
be possible to achieve the simultaneous polymerization of
pivalolactone and ethylene oxide, referred to as dual¬
anionic polymerization, provided that selectivity is
achieved on the bases of nucleophilicity. Alternatively,
sequential addition of ethylene oxide and pivalolactone

43
should yield the desired telechelomer. First polymerizing
pivalolactone is unlikely to succeed because poly(pivalo-
lactone) is insoluble in tetrahydrofuran and decomposes when
reacted with a potassium mirror.
Initial Attempts
Two hydroxy acids were used in the initial attempts to
synthesize poly(oxyethylene-block-pivalolactone) telechelo-
mers: 4-hydroxybenzoic acid and glycolic acid.
Unfortunately, the carboxylate salt of 4-hydroxybenzoic
acid was found to be a poor initiator for pivalolactone,
resulting in long reaction times and broad molecular weight
distributions. Hall26 investigated the rate of initiation
and polymerization of pivalolactone with tetramethylammonium
benzoate, and he found that the rate of initiation is 270%
slower than the rate of propagation. In addition, initia¬
tion with tetramethylammonium benzoate occurred 750% slower
and polymerization occurred 170% slower than initiation and
polymerization with tetraethylammonium pivalate under
similar conditions.
After conversion of 4-hydroxybenzoic acid to the
dipotassium salt by reaction with potassium mirror in
tetrahydrofuran, with precipitation of the product, attempts
to polymerize ethylene oxide were unsuccessful due to a
combination of the low nucleophilicity of the phenoxide
anion and the inhomogeneous conditions.

44
n A
â– i*
(A)n-I*
m B
(A)n-I-(B)m*
h3o+
HO-(A)n-I-(B)m-COOH
step polym.
-[0-(A)n-I-(B)m-C0]p-
If I = B
-[0-(A)n-(B)m+1-CO]p-
Figure 14. Chain-Propagation/Step-Propagation
Polymerization Strategy for Initiation by a
Difunctional Initiator.

45
Glycolic acid is a very hygroscopic, viscous liquid
that is difficult to dry completely, and formation of the
dianion, which precipitates from solution, requires several
days of reaction with a potassium mirror. Attempted dual
anionic polymerization with glycolic acid produced materials
with very little oxyethylene content in about 10% yield.
Attempts to isolate the poly(oxyethylene) segment by selec¬
tively hydrolyzing the unhindered ester with dilute hydro¬
chloric acid were unsuccessful. The resulting material
showed only a decrease in poly(oxyethylene) content.
Synthesis of Defect-Free Telechelomers
One can draw the structure of the defect-free tele-
chelomer (Figure 15), represented by (0E)n-(PVL)m. Initia¬
tion by hydroxypivalic acid could result in defect-free
telechelomer, (OE)n-(PVL)m, since 1) the initiator fragment
is identical to the poly(pivalolactone) segment repeat unit
and 2) both the hydroxyl and carboxylic acid functionalities
are already present.
Formation of Dianionic Initiator
Hydroxypivalic acid is a sublimable white solid that is
easily dried with a modified Abderhalden drying pistol51 and
handled using high vacuum line techniques.
To initiate polymerization of ethylene oxide, hydroxy¬
pivalic acid must first be converted to the dipotassium salt
by reaction with potassium mirror in tetrahydrofuran (Figure
16) . The acidic proton reacts very quickly to form the
hydroxycarboxylate salt (15), which precipitates. The

46
formation of the dipotassium salt (ljj) requires several days
and periodic degassing.
To verify that the dipotassium salt is formed, three
reactions of hydroxypivalic acid in tetrahydrofuran with an
excess of potassium mirror under vacuum were terminated
after 24, 48, and 72 hours, with degassing every 24 hours.
Back-titrating the products with hydrochloric acid, using
phenolphthalein indicator, provided an estimation of the
extent of reaction. The difficulty of completely removing
the precipitated product from the potassium mirror made this
process qualitative at best; however, the information
obtained by titration was verified by proton NMR detection
and integration of the hydroxyl proton signal at 4.5 ppm of
dilute solutions of the products in Silanor-C. After 24
hours only about 20% of the hydroxyl protons reacted, after
48 hours about 80% had reacted, and after 72 hours essen¬
tially complete formation of dianion 16 occurred.
To improve the solubility of the product and the
reactivity of hydroxypivalic acid, 18-crown-6 was added in a
1:1 molar ratio. The addition of 18-crown-6 in tetrahydro¬
furan to a potassium mirror under vacuum formed a dark blue
solution. Subsequent addition of hydroxypivalic acid in
tetrahydrofuran resulted in a violent initial reaction with
the immediate loss of the blue color. The formation of the
dianion was shortened to two days, after which the blue
coloration began to reform; however, substantial precipi¬
tation still occurred.

47
CH,
I J
H—(OCH2CH2)n—(OCH2—C—CO)m—OH
CH3
(OE)n-(PVL)m
Figure 15. Structure of Defect-Free
Poly(pivalolactone-block-oxvethvlene) Telechelomer.

48
ch3
I 0
HOCH2—c—COOH
ch3
K, THF
CH3
HOCH2—C“ COO'K+
ch3
15
K, THF
CH3
+K'OCH2—c— COO‘K+
ch3
16
Figure 16. Formation of the Dipotassium Salt
of Hydroxypivalic Acid.

49
Increasing the ratio of 18-crown-6 to hydroxypivalic
acid to a 2:1 molar ratio resulted in the formation of a
viscous gel that could not be stirred with magnetic stir¬
ring. Under high shear, such as shaking or mechanical
stirring, the gel became less fluid and precipitation
occurred. The precipitant was isolated by filtration,
neutralization with water and then dilute hydrochloric acid,
extraction with methylene chloride, and evaporation of the
methylene chloride, resulting in recovery of the hydroxy¬
pivalic acid starting material. Thus, the gel formation is
probably due to the formation of aggregates.
Attempts to prevent precipitation of the dianion by
using of larger amounts of tetrahydrofuran and by using
N,N,N',N'-tetramethylethylenediamine as a solvent were not
successful.
Dual Anionic Polymerization
Although the dual-anionic polymerization approach
(Figure 17) is interesting, there are many undesired
reactions that can occur. In practice, only a limited
amount of ethylene oxide is incorporated into the product,
indicating that the alkoxide anion is reacting with pivalo-
lactone in such a way as to prevent reaction with ethylene
oxide. One likely possibility is attack at the methylene
carbon of the lactone by the alkoxide anion (Figure 18) ,
thereby converting the alkoxide anion into a carboxylate
anion and making further reaction with ethylene oxide
impossible.

50
ch3
+KOCH2—c-COOK+
CHg
13
ch3
I a
H—(OCH2CH2)m—(OCH2—C—CO)n-OH
CHo
Figure 17. Reaction Scheme for the Dual-Anionic
Polymerization of Ethylene Oxide and Pivalolactone.

51
'O— CA/WWWWV' CH2*0— CH2C(CH3)2— c— O"
Figure 18. Possible Undesired Reaction of the
Alkoxide Ion with Pivalolactone During
Dual-Anionic Polymerization.

52
Sequential Addition Polymerization
Figure 19 presents the sequential addition polymeriza¬
tion reaction scheme used to produce defect-free tele-
chelomers (OE) n-(PVL) jj. Ethylene oxide is vacuum trans¬
ferred into a solution of 16 in tetrahydrofuran, and the
reaction mixture is stirred at 5°C for several days. The
product, a-hydro-w-(hydroxypivalyloxy)poly(oxyethylene)
(17), is isolated by evaporation of the tetrahydrofuran,
dissolving the residue in water, acidifying with dilute
hydrochloric acid, extracting with methylene chloride, and
precipitating the product in diethyl ether. Deprotonation
of the acid proton produces the potassium carboxylate (18),
which is used to polymerize pivalolactone in tetrahydro¬
furan, under argon. The tetrahydrofuran is evaporated under
reduced pressure and methylene chloride is added to dissolve
as much of the residue as possible. The resulting solution
is shaken with dilute hydrochloric acid and separated. The
defect-free telechelomer, (OE)n-(PVL)m, is isolated by
precipitation in diethyl ether or by evaporation of the
methylene chloride.
Control of the Soft-Segment Length
The proton NMR of (OE)34-PVL (17) (Figure 20) is very
simple, having three large singlets at 3.7, 4.6, and 1.2
ppm, resulting from the poly(oxyethylene) methylene protons
(a) , the pivalic acid end-group methylene protons (b) , and
the pivalic acid methyl protons (c) , respectively. The
poly(oxyethylene) segment length (n) is easily determined by

53
proton NMR integration and verified by titration of the acid
end group and SEC.
The polymerization of ethylene oxide to form 17 was
conducted at various conditions, and the percent yield,
number-average molecular weight determined by titration, and
the SEC molecular weight distribution of each product, 17.
is listed in Table 4. Due to the inhomogeneous initiator,
the products in Table 4 all have molecular weights higher
than that predicted by the stoichiometric ratio (Mn Obs);
however, some control of n is obtained by varying the
conditions.
In a typical experiment, the ratio of monomer to
initiator was 1 to 20, the ethylene oxide polymerization was
given a static argon atmosphere that was open to a mineral
oil bubbler to allow the release of sudden pressure, and the
reaction temperature was maintained at 5°C for a specific
number of days in order to keep the volatile ethylene oxide
in the reaction solution. In the first polymerization, the
reaction was stirred at 5°C for one day, allowed to warm to
room temperature and stirred for two additional days. The
yield was slightly diminished and the polydispersity was
very much improved by the precipitation of the product from
diethyl ether, removing any low molecular weight polymer.
The resulting product had Mn = 3780, 280% larger than that
predicted by the initiator to monomer ratio. This dif¬
ference is most likely due to the inhomogeneous nature of
the dianionic initiator.

54
CH3
+K'OCH2—C—COO'K+
ch3
IS
o
1. m/ \ ,THF
2. H30+
ch3
i J
H-(OCH2CH2)m-OCH2—C-COOH
17 CH3
KOH, MeOH
CH3
l J
H-(OCH2CH2)m-OCH2—C-COO'K+
IS
I
CH,
THF
H—(OCH2CH2)m—(OCH2—C-*CO)n-OH
CHo
(OE)n-(PVL)
m
Figure 19. Reaction scheme for the Synthesis
of Defect-Free Telechelomers by Sequential
Chain-Propagation Polymerization.

55
Figure 20. Proton NMR of (OE)34~PVL, 12*

56
Table 4. Results of Polymerization of
Ethylene Oxide (EO) with Initiator 11
Under Various Conditions to Form
Poly(oxyethylene) 17
Init.
moles
OE
moles
Mn
Calc
Mn
Obs
Mw/Mn
%
Yield
Conditions
0.010
0.20
1000
3780
1.03
82
25 ml THF, Ar, 5°C 1 day,
RT 2 days
0.010
0.20
1000
1660
1.13
88
25 ml THF, Ar, 5°C 3 days
0.010
0.20
1000
1610
1.10
85
100 ml THF, Ar, 5°C 3 days
0.010
0.20
1000
1570
1.10
60
25 ml THF, Ar, 5°C 2 days
0.005
0.10
1000
1590
1.05
84
50 ml THF, Ar, 0.005 moles
18-crown-6, 5°C 3 days
0.005
0.10
1000
6430
-
65
50 ml TMEDA, Ar, 5°C 4
days
0.012
0.22
890
1050
1.30
83
100 ml THF, vacuum, 5°C 3
days
Maintaining the reaction at 5°C for 3 days produced 17
with a lower molecular weight, Mn = 1660, and a higher
molecular weight distribution, Mw/Mn = 1.13. About the same
results were obtained with the use of 4 times the amount of
tetrahydrofuran solvent. Decreasing the reaction time to
two days at 5°C resulted in a lower molecular weight 17, Mn
= 1570, in lower yield. The addition of 18-crown-6 gave the
best results, producing 17 with Mn = 1590 and Mw/Mn = 1.05
in good yield, 84%. This polymer, .17, has an average of 34
ethylene oxide repeat units, n.
The use of N,N,N',N1-tetramethylethylenediamine
produced a high molecular weight 17, Mn = 6430, in low

57
yield. Polymerizing ethylene oxide in a sealed reaction
flask under vacuum at 5°C produced a good yield of 17 with
Mn = 1050; however, the polydispersity of this material was
very large, Mw/Mn = 1.30, and the molecular weight was too
low to precipitate from diethyl ether.
Control of the Hard-Seoment Length
Once 17. is formed, the polymerization of pivalolactone
to build the hard segment of the telechelomer is straight¬
forward. The acidic proton is easily removed with potassium
hydroxide in methanol to form the carboxylate salt, which is
used to polymerize pivalolactone in tetrahydrofuran, under
argon. The poly(pivalolactone) hard-segment length is
controlled by the ratio of carboxylate to pivalolactone, and
(0E)n-(PVL)m telechelomers were synthesized with a constant
poly(oxyethylene) soft-segment length, n = 34, and varying
poly(pivalolactone) hard-segment length, m = 5, 12, and 16.
The proton NMR of (OE)34-(PVL)^6 (Figure 21) is
identical to the proton NMR of (OE)34-PVL (17) (Figure 19),
except for the heights and integrations of the poly(pivalo¬
lactone) singlets at 4.6 (b) and 1.2 ppm (c) . The poly-
(pivalolactone) segment length (m) is easily determined by
proton NMR integration and verified by SEC analysis, using
the Mark-Houwink parameters from the (PVL)m-(0E)24”(pvL)m
oligomers.

58
Figure 21. Proton NMR of (OE)34-(PVL)1$.

59
Analysis of Microphase Separation
Figure 22 presents the DSC curves of the (OE) 34”(PVL)in
defect-free telechelomers. Each sample shows a weak glass
transition around -50°C and two melting endotherms, a high
temperature endotherm for the hard phase and a lower
temperature endotherm for the soft phase. Although the
samples were quenched from 50°C, the soft phase of these
telechelomers exhibit crystallization, indicating that a
high degree of microphase separation exists.
Because the soft phase of these samples are semi¬
crystalline, they do not lend themselves to the type of soft
phase analysis used for the triblock oligomers. The Tg°bs is
not a reflection of the soft segment purity since only the
non-crystalline soft segments participate in Tg°bs and, when
crystallization occurs, the amorphous regions are due to
chain folding and microphase mixing at the interface. Also,
calculation of the soft segment segregation assumes that the
entire soft phase participates in the change in heat
capacity at Tgobs.
The hard-segment crystalline sequence propagation
probability, pH (Equation 12), was a good approximation of
SRjj for the (PVL)m-(OE) 24-(PVL)m oligomers, and the calcu¬
lated values of pH for the (OE) 34“(PVL)in defect free tele¬
chelomers (Table 5) show that the sample for m = 12 and 16
have very high hard-segment purity. The 0.73 value of pH
for (OE)34-(PVL)5 indicates that hard segment microphase
mixing occurs in this sample.

Endothermic ->
60
Figure 22. DSC Scans of (OE) 34-(PVL)ln.

61
Because the soft phase of the (OE)34”(PVL)m telechelo¬
mers also exhibit crystallization, Equation 12 can also be
applied to the soft phase of these materials:
ps = EXP[(1/Tms - l/Tmobs)*deltaH/R] (13)
where Tms represents the melting point of the soft-segment
crystalline homopolymer, deltaH represents the heat of
fusion per mole of repeat unit of the crystalline soft-
segment, and ps represents the soft-segment crystalline
sequence propagation probability. In this case, ps should
be a good approximation for Mss. The values of ps for the
(OE) 34-(PVL)m telechelomers, listed in Table 5, were
calculated from Equation 13 using a value of 1980 cal/mole
of repeat unit for deltaH57 and a value of 37.4°C for Tros.57
The values of ps for the (OE)34-(PVL)m telechelomers are all
greater than unity, indicating essentially complete soft-
phase microphase separation occurs for the soft segments
capable of crystallizing.
Table 5. Results of DSC Analysis of Microphase
Separation of (OE)34-(PVL)m Defect-Free Telechelomers.
Hard
Phase
Soft Phase
m
wH
m obs
im
m H
pH
m obs
rn ObS
1m
PS
5
0.25
142 °C
174°C
0.73
-50°C
38 °C
1.00
12
0.45
199 °C
201°C
0.91
-53 °C
u
0
CM
1.04
16
0.52
207 °C
205°C
1.09
-52 °C
50°C
1.13

62
Chapter Summary
Defect-free telechelomers, (OE)n-(PVL)m, are produced
by initiation with the dipotassium salt of hydroxypivalic
acid in sequential anionic chain-propagation polymerization
of ethylene oxide and pivalolactone. The DSC analysis of
microphase separation of (OE)34-(PVL)m defect-free tele¬
chelomers indicate that these materials exhibit excellent
microphase separation, allowing both the hard and soft
segments to crystallize. Essentially complete microphase
separation occurs for m = 12 and 16. In the case for m = 5,
the hard segment is the minor component, and microphase
separation is not complete.

STEP POLYMERIZATION OF TELECHELOMERS
Introduction
The (OE)n-(PVL)m telechelomers exhibit excellent
microphase separation; however, they do not have thermo¬
plastic characteristics due to their low molecular weights
and lack of more than one hard segment per polymer molecule.
The step polymerization of the telechelomers to [(0E)n-
(PVL)m]p segmented copolymers (Figure 23) represents an
important aspect in the synthesis of poly(oxyethylene-block-
pivalolactone) thermoplastic elastomers.
The gem-dimethyls that give the poly(pivalolactone)
hard segment excellent solvent resistance also make the
sterically hindered carboxylic acid very difficult to step
polymerize. Wagener and Wanigatunga38 were unable to
polymerize pivalolactone based telechelomers using a number
of standard solution polyesterification reagents, including
l-methyl-2-bromopyridinium chloride/tri-n-butylamine, N,N'-
bis (2-oxo-3-oxo-azolidinyl)phosphorodiamidic chloride/tri-
ethylamine, triphenyl phosphite, hexachlorocyclotriphospha-
triazene, trif luoroacetic acid/methylene chloride, and
methylsulfonic acid/phosphorus pentoxide. Several attempts
at melt esterifications also were unsuccessful, including
heating without catalyst and heating with antimony trioxide
or titanium tetrabutoxide.
63

64
h3c o
•* I II
H-(OCH2CH2)n (OCH2—C—C)m—OH
H3C
H--(OCH2CH2)n-
H3C
O
ii
â– (OCH2-C-C)m
HqC
f“OH
P
((OE)n-(PVL)m)p
Figure 23. Step Polymerization of (OE)n-(PVL)m
to Segmented Copolymer [(OE)n-(PVL)m]p.

65
Wagener and Wanigatunga38 decided to attempt conversion
of the hindered carboxylic acid end group to an unhindered
carboxylic acid by reaction with d,1-alanine. However,
after reaction with titanium tetrabutoxide at temperatures
over 200°C, the d,1-alanine sublimed from the reaction melt
upon application of vacuum, resulting in a segmented
copolymer with a SEC Mn = 30,000 versus poly(styrene). This
reaction, termed alanine-mediated polymerization, is the
first example of amino acid or zwitterionic catalyzed
polyesterification.
Wagener, Wanigatunga, and Zuluaga58 conducted a model
study of the esterification of 2-(2-methoxyethoxy)ethanol
with pivalic acid, and they observed a ten fold increase in
the ester acid ratio with catalytic amounts of alanine at
110°C. Zuluaga conducted a detailed comparison of esterifi¬
cation by alanine alone, titanium tetrabutoxide alone, and
alanine with titanium tetrabutoxide, and he observed that
all three systems gave about the same ester acid product
ratio. This study included esterification at 110°C under
argon and at room temperature under vacuum, using 1 mole %
of the catalysts; however, Zuluaga reports having difficulty
obtaining reproducible results (Zuluage, F. personal
communication) .
Model Study
In contrast to the original polyesterification condi¬
tions, the existing model studies involved the use of small
organic molecules, 2-(2-methoxyethoxy)ethanol with pivalic

66
acid, and high temperatures and vacuum could not be applied
simultaneously. In order to model polyesterification
reactions more closely, a-hydroxypoly(pivalolactone) oligo¬
mers were examined under a number of different polyesterifi¬
cation conditions (Table 6). The yields reported in Table 6
are the yields of polymer obtained from precipitating the
crude product in diethyl ether from methylene chloride or
N,N-dimethylacetamide. Low molecular weight poly(pivalo¬
lactone) , 500 g/mole or less, does not precipitate easily
and is therefore separated from the isolated product.
Thermogravimetric (TGA) analysis of a-hydroxypoly-
(pivalolactone) with Mn = 500 and 1180 g/mole (Figure 24)
shows a marked difference in the thermal stability of the
two poly(pivalolactone) oligomers. The lower molecular
weight polymer (a) shows a long, slow decomposition that
begins at very low temperatures, with 8% weight loss
occurring at 200°C. The higher molecular weight polymer (b)
shows good thermal stability up to 200°C and decomposes
quickly after 300°C. In both cases, there is no evidence of
esterification with the loss of water upon heating.
The TGA results appear to indicate that the melt
esterification of low molecular weight a-hydroxypoly(pivalo¬
lactone) should be conducted in two stages. The reaction
should begin at the lowest possible temperatures to minimize
decomposition. Then, after the dimer has formed, the
polymer is more thermally stable, and higher temperatures
could be utilized

67
Figure 24. TGA Scans of a-Hydroxypoly(pivalolactone)
with Mn = 500 (a) and Mn = 1180 (b).

68
Table 6. Results of Melt Polyesterification of
a-Hydroxy-w-Hydropoly(pivalolactone), (PVL)n,
Under Various Conditions.
Exp
#
Initial
Mn
Product
% Yield Mn
Conditions
1
500
10
«1000
Ti(OBu)4 Ar 100°C 1 hr, Ar 100-
150°C 0.5 hr, vacuum 150°C 0.5
hr
2
500
7
«1000
Alanine Ar 100°C 1 hr, Ar 100-
150°C 0.5 hr, vacuum 150°C 0.5
hr
3
500
20
«1000
Alanine Ar 100°C 1 hr, vacuum
100°C 0.5 hr, Ti (OBu) 4 Ar 100-
150°C 0.5 hr, vacuum 150°C 0.5
hr
4
500
53
1180
Ti (OBu) 4 Ar 150-180°C 1 hr, Ar
180-230°C 0.5 hr, vacuum 230°C
0.5 hr
5
500
51
1020
Alanine Ar 150-180°C 1 hr,
vacuum 180°C 0.5 hr, Ti(0Bu)4
Ar 180-230°C 1 hr, vacuum 230°C
0.5 hr
6
1180
58
1270
Ti(OBu)4 Ar 200°C 1 hr, Ar 200-
250°C 0.5 hr, vacuum 250°C 0.5
hr
In experiments 1, 2, and 3 in Table 6, melt esterifica¬
tions of a-hydroxypoly(pivalolactone) with Mn = 500 g/mole
were conducted at temperatures between 100 and 150°C. In
each case, however, only small amounts of the dimerized
material were obtained, with titanium and d,1-alanine giving
the highest yield, 20%. Proton NMR analysis indicates that
substantial decomposition occurred in each case. No
evidence of nitrogen was detected by proton NMR or elemental
analysis of the products of reactions 2 and 3.

69
The melt esterifications of a-hydroxypoly(pivalo-
lactone) with Mn = 500 g/mole at higher temperatures,
Experiments 4 and 5 in Table 6, produced dimerized product
in yields around 50%. Titanium tetrabutoxide alone,
Experiment 4, and titanium tetrabutoxide with d,1-alanine,
Experiment 5, gave similar results; however, the number-
average molecular weight of the product from experiment 5 is
slightly lower due to the presence of low molecular weight
polymer. Figure 25 presents the SEC traces of the starting
material (a) and the products from Experiment 4 (b) and
Experiment 5 (c) . Again, no evidence of nitrogen was
observed for the product in Experiment 5.
The melt esterification of a-hydroxypoly(pivalolactone)
with Mn = 1180 g/mole, using alanine and titanium tetra¬
butoxide at 200-250°C, Experiment 6, resulted in decom¬
position and the recovery of starting material with slightly
higher molecular weight and higher polydispersity, probably
resulting from transesterification reactions.
Melt Esterification of Telechelomers
Melt esterifications of the (OE)n-(PVL)m telechelomers
were attempted using 1 mole % titanium tetrabutoxide, with
and without d,1-alanine, at temperatures between 180 to
250°C. Low molecular weight segmented copolymers, typically
of the size of the dimer and trimer, were produced. In a
single experiment, the pentamer of (OE)34-(PVL), Mn =
16,000 by SEC (Figure 26), was produced using titanium
tetrabutoxide and d,1-alanine.

70
SEC PROGRAMS Advanced Edition
Figure 25. SEC Analysis of Melt Esterification of
a-Hydroxypoly(pivalolactone): (a) Starting Material,
Mn = 500, (b) Product of Titanium Catalyst
(Experiment 4 Table 6), Mn = 1180, and (c) Product
of Titanium Catalyst with d,1-Alanine (Experiment 5),
Mn = 1020.

71
SEC PROGRAMS Advanced Edition
Figure 26. SEC Trace of (OE)34-(PVL)(a),
Mn = 3,200, and [(OE)34“(PVL)16]5 (b), Mn = 16,000.

72
The methyl region of the proton NMR of [(OE)34~
(PVL)i6]5 product (Figure 27) contains several small peaks,
evidence that this product contains a significant amount of
partially decomposed poly(pivalolactone) segments. The DSC
scan of [(OE)34-(PVL)16]5 is presented in Figure 28. The
segmented copolymer produced from alanine-mediated melt
esterification shows, relative to that of the original
telechelomer in Figure 22, a slight decrease in the hard-
phase melting point with a large decrease in the heat of
fusion, resulting in a much smaller signal. The melting
point of the soft phase also decreased slightly, relative to
that of the telechelomer.
Chapter Summary
Alanine-mediated melt esterification of the (0E)n-
(PVL)m defect-free telechelomers with titanium tetrabutoxide
was successful in producing low molecular weight polymers
containing a substantial amount of decomposed poly(pivalo¬
lactone) segment.
Model studies using low molecular weight a-hydroxypoly-
(pivalolactone) indicate that melt esterification of
poly(pivalolactone) with titanium tetrabutoxide catalyst is
not a viable route to high molecular weight step polymer.

73
H,C
O
ii
H-f (OCH2CH2)34 (OCH2—C-C) 16-oh
HaC Jn
Figure 27. Proton NMR of [(OE)34-(PVL)ig]5

Endothermic -»
74
Temperature (°C)
Figure 28. DSC Scan of [(OE)34-(PVL)16]5.

EXPERIMENTAL
Instrumentation
NMR data were obtained on a Varian XL-200, and all
chemical shifts are reported in units of ppm down field from
tetramethylsilane internal standard. Silanor-C or chloro-
form-d was used to make dilute solutions of the samples
(about 0.003 g/ml), and to samples containing poly(pivalo-
lactone) trifluoroacetic acid was added until a clear
solution formed. All NMR sample solutions were filtered
through glass wool prior to analysis.
All DSC and TGA data were obtained on a Perkin-Elmer 7
Series Thermal Analysis System equipped with a TAC7 micro¬
controller and a PE7500 computer equipped with Perkin-Elmer
TAS7 software. Both instruments were calibrated by a two
point method. The TGA was calibrated with nickel and
perkalloy curie point standards with dry nitrogen purge gas
(50 mL/min) . The DSC was calibrated with cyclohexane and
indium with dry helium purge gas (25 ml/min) for subambient
operations and with indium and tin with dry nitrogen purge
gas (25 ml/min) for operation above 50°C. Reported melting
point temperatures represent the peak of the melting
endotherm, and reported glass transitions represent the
temperature of the midpoint of the glass transition. All
reported DSC results are the average of 2-8 scans, at a rate
75

76
of 20°C/min, of each sample. In each case reported, the
variance was less than 5%.
All viscometry data were obtain on an Ace Scientific
viscometer, ubderhalden type, using a Haake E2 constant
temperature waterbath maintained at 30 ± 0.01°C.
Gas Chromatograph data were obtained on a Hewlett
Packard model 5880A Series Gas Chromatograph with accompany¬
ing 5880A Series Terminal, using Helium carrier gas and
flame vaporization.
Polymerizations of ethylene oxide were maintained at 5
± 1°C using a Precision Scientific Precision Lo-Temptrol low
temperature bath containing Sears Antifreeze pumped through
a copper coil immersed in an insulated isopropanol bath.
Vacuum line experiments were performed on a high vacuum
line (10-6 mmHg) constructed by the University of Florida
Glass Shop using two Sargent Welch model D-1400 vacuum
pumps, an Ace Glass mercury diffusion pump, two Ace Glass
cooling traps, an Ace Glass mercury manometer, Ace Glass
high vacuum stopcocks, and an argon inlet with mineral oil
bubbler. Argon was passed through a concentrated sulfuric
acid bubbler, a sodium hydroxide column, and a calcium
sulfate column.
All SEC data were obtained on a Waters 6000A Liguid
Chromatograph, equipped with concentration sensitive
differential refractometer detector. All data was collected
and analyzed on a Zenith Personal Computer model 48 equipped
with a MetraByte multi-IO card and an Epson dot matrix

77
printer. Sample solutions of 0.005 g/ml in methylene
chloride containing 1% by volume trifluoroacetic acid were
filtered through 0.45 nm filters and analyzed using TSK 5000
Á and 3000 Á columns. For analysis of poly(oxyethylene)
polymers, the instrument was calibrated with narrow molecu¬
lar weight distribution poly(oxyethylene) glycols. For
analysis of Poly(oxyethylene-block-pivalolactone) polymers,
the instrument was calibrated with narrow molecular weight
distribution poly(styrene) standards by universal calibra¬
tion. From the viscometry determination of [n] for the
poly(styrene) standards (Table 7) , the Mark-Houwink param¬
eters for poly(styrene) in methylene chloride containing 1%
trifluoroacetic acid were determined, K = 0.010 ml/g and a =
0.71, by a plot of Equation 2 (Figure 29).
Table 7. Intrinsic Viscosities ([n]),
Number-Average Molecular Weights (Mn), and
Polydispersities (Mw/Mn) of Poly(Styrene)
Standards Used for Universal SEC Calibration.
Mn
9000
17500
37000
48900
Mw/Mn
1.06
1.06
1.06
1.06
[n] dl/g
0.062
0.105
0.172
0.209

In In]
78
Figure 29. Plot of Mark-Houwink Equation
(Equation 2) for Poly(styrene) Standards
Used for Universal SEC Calibration.

79
SEC Programs
General Description
The software for SEC data collection and analysis,
entitled SEC Programs, was written by this author and
compiled using Microsoft QuickBASIC compiler version 4.5,
incorporating MetraByte's DASC0N1.0BJ and some assembly
language routines found in Cresent Software QuickPak
Professional. The complete listing of SEC Programs is
presented in the APPENDIX.
SEC Programs is a menu-driven and user-friendly program
that is capable of acquiring data, storing data, recalling
previously stored data, analyzing data, calibrating the
instrument, and printing data plots. SEC Programs has many
advanced features including the simultaneous monitoring of
the two detectors, automatic universal calibration, data
exporting to an ASCII file, graphic display of up to 10
samples, automatic and manual rescaling, real-time graphic
display of data acquisition, and run-time error checking.
Additional time-saving conveniences include single-key menu
selection, high-speed data plotting, and file directory
display with file selection by arrow keys.
Calibration
SEC Programs utilizes the peak position calibration
method, or the Hamielec method,59 for narrow molecular
weight distribution standards with known SEC peak molecular
weights (Mp) and polydispersities according to the following
equation:

80
InMp = InD1 - D" • Vp
(14)
where Vp represents the measured SEC peak retention volume
and D' and D" represent calibration constants. A plot of
InMp versus Vp produces a line with slope = -D" and inter¬
cept = InD'. This linear calibration method is effective,
provided that correlations greater than 0.99. obtained.
Column spreading is then measured by reexamining the
raw data for each calibration standard, and experimental
values for the polydispersities (MnexP/MwexP) are determined
according to the following equations42:
MwexP = 2[F(V) *M(V) ]
Mnexp = 1/2[F(V)/M(V)]
(15)
(16)
where F(V) represents the height of the normalized SEC curve
at retention volume V and M(V) represents the molecular
weight at retention volume V. The discrepancy between the
true and the experimental molecular weight averages can be
directly related to each other by a single Gaussian function
correction factor,60 and SEC Programs utilizes the Gaussian
function correction factor to approximate instrumental peak
broadening by a standard deviation (a), which in the small
range of the calibration standard elution is assumed to be
independent of retention volume. The value of a is deter¬
mined for each of the calibration standards, using the known
Mwtrue/Mntrue and the calculated values of D" and
Mwexp/Mnexp:
a = [In(MwexP/MnexP) - ln(Mwtrue/Mntrue)]1/2/D"
(17)

81
Sample Analysis
Sample analysis by SEC Programs includes the Gaussian
function correction factor,60 which employs a, and the
calibration constants D' and D":
Mw = EXP[-(l/2)(D"-a)2]*E[F(V)-D'-EXP(-D"*V)] (18)
Mn = EXP[(1/2)(D"’a)2]/E[F(V)/Dl•EXP(-D"V)] (19)
The column spreading can vary with retention volume61;
therefore, the user is prompted to input the value of a,
based upon the calculated values of a the standards.
Yau, Kirkland, and Bly42 have shown that the error in
the calculations of Mw and Mn according to eguations 18 and
19 are dependent upon the column parameters a and D":
Error (Mw) = EXP[ (1/2) (a-D") 2 - l] (20)
Error(Mn) = -EXP[-(l/2)•(a-D")2 - 1] (21)
And, in all SEC experiments, the error in molecular weight
determination was less than 0.4%.
Chemicals
All solvents used were reagent or HPLC grade. Tetra-
hydrofuran was refluxed over potassium-sodium alloy (2:1)
overnight, distilled onto fresh potassium-sodium alloy
(2:1), degassed and stored under reduced pressure for vacuum
distillation into the reaction flask. N,N,N',N'-tetra-
methylethylenediamine was degassed, vacuum distilled onto
calcium hydride and stirred overnight, vacuum distilled onto
a potassium mirror, then vacuum distilled into the reaction
vessel. Anhydrous diethyl ether was taken from freshly
opened containers only. All solvents used in SEC and

82
viscometry analysis were filter through 0.5 jum filters prior
to use. Purified water was obtained from a Milipore water
purification apparatus.
The narrow molecular weight distribution poly(oxyethyl-
ene) glycols were donated in pure form by Union Carbide.
When needed dry, the poly(oxyethylene) glycols were dried
under vacuum at 100°C in a modified drying pistol for
several days.
Pivalolactone, donated in pure form by Dr. H. K. Hall,
was dried over calcium hydride at reduced pressure overnight
then distilled at reduced pressure just before use.
Ethylene oxide (Aldrich) was cooled to -30°C, opened in
the hood and poured onto calcium hydride, degassed, vacuum
distilled onto fresh calcium hydride, and stored under
reduced pressure at -30°C.
Potassium metal (Aldrich) was cut in hexane, placed
into a sidearm of the reaction flask, evacuated to high
vacuum, and distilled directly into the reaction flask.
Hydroxypivalic Acid (American Tokyo Kasie) was dried in
a vacuum desiccator containing calcium sulfate for several
days, transferred to an ampule containing a breakseal, dried
by dynamic high vacuum for several days, and flame sealed in
the ampule.
Gold label 18-crown-6 (Aldrich) was used as received
from unopened 1 g containers, and all transfers were done in
a glovebag under argon. Reagent grade 18-crown-6 (Aldrich)
was purified by precipitating its complex with nitromethane

83
and when removing the nitromethane with high vacuum. To a
dried solution of 18-crown-6 in diethyl ether, nitromethane
was added, forming a white precipitate that was filtered,
placed into a vacuum desiccator under dynamic vacuum for
several days, placed into a round-bottom flask, kept under
dynamic high vacuum (10-6 mmHg) for several days, and stored
under argon. Subsequent transfers were conducted in a
glovebag under argon.
Succinic anhydride (Aldrich) was dried under dynamic
vacuum, sublimed under vacuum into an ampule containing a
breakseal, flame sealed in the ampule, and sublimed directly
into the reaction flask.
D,1-Alanine (Aldrich) was reprecipitated from water,
vacuum sublimed, and stored in a desiccator containing
calcium sulfate.
Titanium tetrabutoxide (Aldrich) was vacuum distilled
and stored under argon.
Standardized potassium hydroxide solutions in methanol
were made from fresh containers of potassium hydroxide and
standardized with dried potassium biphthalate with phenol-
phthalein indicator.
Syntheses
Synthesis of 7
In a 250-ml round-bottom flask fitted with condenser,
magnetic stirbar, and calcium sulfate drying tube, 10.0 g
(10 mmoles) of poly(oxyethylene) glycol, 1000 g/mole, and
10.0 g (100 mmoles) of succinic anhydride were refluxed for

84
24 hours in 100 ml of toluene with stirring. The toluene
was removed by rotovap. The resulting white residue was
dissolved in 100 ml of deionized water, stirred for 30
minutes, filtered, then extracted with four 25-ml portions
of methylene chloride. The combined methylene chloride
extracts were washed with two 25-ml portions of deionized
water and dried over anhydrous sodium sulfate for at least
two days before being filtered. The methylene chloride was
rotovapped down to a concentrated solution and transferred
to a drying pistol. The product was dried to a constant
weight under vacuum while heating with refluxing water,
resulting in a 92% yield. Molecular weight: 1260 (NMR) and
1260 g/mole (titration). Elemental analysis: theoretical
52.7%C and 8.3%H, found 52.1%C and 8.4%H.
Synthesis of 8
After drying under high vacuum at 100°C for several
days, 1.15 g (0.91 mmoles) of 7 was dissolved in 75 ml of
dry tetrahydrofuran by vacuum transfer. The flask contain¬
ing 7 in tetrahydrofuran was sealed and attached to a 250-ml
reaction flask containing a side arm for potassium metal and
a magnetic stirbar. Approximately 1 g of potassium was
placed into the side arm and the flask was flame sealed and
taken to high vacuum. The potassium was distilled into the
reaction flask under dynamic vacuum, forming a mirror, and
the side arm was removed by flame sealing. The stopcock to
the dynamic vacuum was closed and the tetrahydrofuran
solution of 7 was allowed to pour onto the mirror, with

85
immediate bubbling. The reaction was periodically degassed
to remove hydrogen. After 24 hours, the tetrahydrofuran
solution was decanted into a second round-bottom flask and
rotovapped, resulting in 1.2 g of a white powder which was
dried by high vacuum and stored under argon.
Synthesis of (PVL)m-(OE)n-(PVL)in
Macromolecular initiator 8 was quickly weighed, 1.0 g,
and placed into a round-bottom flask with stirbar and
attached to the vacuum line. The flask was taken to high
vacuum and 40 ml of dry tetrahydrofuran was vacuum trans¬
ferred into the flask. This initiator solution, 0.020
mmoles/ml, was stored under argon.
To a 250-ml round-bottom flask with magnetic stirbar
under argon, was added 10 ml of the initiator solution by
syringe. With stirring, pivalolactone, 9.9 mmoles/ml, was
added by syringe to obtain initiator to monomer ratios of
1:5, 7, 9, 12, 16, and 24. The reaction stirred under argon
overnight, and the product was isolated by evaporation of
the tetrahydrofuran under reduced pressure. Elemental
Analysis: (PVL)5-(OE)24-(PVL)5 theoretical 54.3%C, 7.9%H,
and 3.3%K, found 54.6%C, 8.2%H, and 1.4%K; (PVL)7-(OE)24-
(PVL)7 theoretical 54.8%C, 7.9%H, and 2.7%K, found 55.0%C,
8.1%H, and 1.3%K; (PVL)9-(OE)24-(PVL)9 theoretical 55.5%C,
7.9%H, and 2.5%K, found 55.5%C, 8.3%H, and 1.1%K; (PVL)12-
(OE)24“(PVL)12 theoretical 56.5%C, 8.0%H, and 2.0%K, found
55.7%C, 8.0%H, and 1.1%K; (PVL)16-(OE)24-(PVL)16 theoretical
57.0%C, 8.0%H, and 1.7%K, found 55.3%C, 8.0%H, and 1.0%K;

86
(PVL) 24“(OE) 24”(pvij) 24 theoretical 57.7%C, 8.0%H, and 1.3%K,
found 57.1%C, 8.0%H, and 1.0%K.
Synthesis of 10
In a dry box, 7.59 g (50 mmoles) of t-butyldimethyl-
silyl chloride and 4.82 g (70 mmoles) of imidazole were
place into a 250-ml round-bottom flask with magnetic
stirbar. The flask was attached to the vacuum/argon line,
and, under argon, 7.60 g (50 mmoles) of 2-benzoxyethanol and
25 ml of N,N-dimethylformamide was added by syringe. The
reaction was stirred in an oil bath at 50°C for 30 hours.
Then, 50 ml of hexane was added, the solution was trans¬
ferred to a separatory funnel, and the solution was washed
with four 25-ml portions of purified water. The organic
layer was dried over anhydrous magnesium sulfate and
filtered. The hexane was evaporated and the product was
vacuum distilled at 1 mmHg and 140°C. 10.8 g, 80% yield, of
a colorless oil was obtained in 97.3% purity by gas chroma¬
tography .
Synthesis of 11
In a high pressure flask, 10.0 g (37.5 mmoles) of 10.
1.0 g of 10% palladium on charcoal, and 100 ml of dry
tetrahydrofuran were mixed. The flask was placed into a
Parr Shaker and hydrogenated for 24 hours at 30 psig until
hydrogen uptake was complete. The resulting mixture was
filtered and rotovapped. The product was isolated by
distillation at 68 °C and 1 mmHg in 97.6% purity by gas
chromatography.

87
Synthesis of 12
Using vacuum-line and breakseal techniques, 2.0 g (10
mmoles) of ¿I was freeze-pump-thawed several times and
sealed in a ampule. 11 was stirred by magnetic stirring in
50 ml of dry tetrahydrofuran over a potassium mirror for 3
days with periodic degassing. The precipitated product and
the tetrahydrofuran were decanted into the receiving flask
and flame sealed.
Synthesis of 13
A flask containing 2.0 g (10 mmoles) of 12 in 50 ml of
dry tetrahydrofuran under vacuum was attached to the vacuum
line, and 10 ml (200 mmoles) of ethylene oxide was vacuum
transferred directly into the flask. The flask was given a
static argon atmosphere, open to a mineral oil bubble to
release any sudden pressure, and stirred at 5°C for 3 days.
The tetrahydrofuran was evaporated at reduced pressure and
the residue was dissolved in 30 ml of purified water.
Dilute hydrochloric acid was added until the solution tested
positive to litmus paper. The water solution was extracted
with four 20-ml portions of methylene chloride. The
combined methylene chloride extracts were dried over calcium
sulfate and then filtered. The methylene chloride was then
poured into 500 g of cold diethyl ether forming a white
precipitant which was immediately filtered and dried in a
vacuum desiccator over calcium sulfate. The isolated yield
was 7.6 g, 70% yield.

Synthesis of 14
To a reaction flask attached to the vacuum line, an
ampule containing 1.0 g (5 mmoles) of 12 and 50 ml of tetra-
hydrofuran and an ampule containing 2.5 g (25 mmoles) of
succinic anhydride were attached. 5 ml (100 mmoles) of
ethylene oxide was vacuum transferred directly into the
flask. The flask was given a static argon atmosphere, open
to a mineral oil bubbler, and the initiator solution was
allowed to polymerize ethylene oxide with magnetic stirring
at 5 °C for 3 days. Then, the succinic anhydride was
sublimed directly into the flask, and the flask was allowed
to warm to room temperature and stir overnight. The
tetrahydrofuran was evaporated at reduced pressure and the
residue was dissolved in 20 ml of methylene chloride. The
methylene chloride was added to 250 g of diethyl ether
forming a light brown precipitant in 80% yield.
Synthesis of 16
Using vacuum-line and breakseal techniques, 1.2 g (10
mmoles) of dry hydroxypivalic acid was taken to high vacuum
in an ampule. 25 ml of dry tetrahydrofuran was vacuum
transferred directly into the ampule, and the ampule was
flame sealed.
The ampule containing the hydroxypivalic acid in
tetrahydrofuran was attached to a reaction vessel. In cases
where 18-crown-6 was used, a second ampule containing 5
mmoles of 18-crown-6 in 10 ml of tetrahydrofuran was also
attached. Approximately 1 g of potassium was placed into a

89
side arm, and the flask was flame sealed and taken to high
vacuum. The potassium was distilled into the reaction flask
under dynamic vacuum, forming a mirror, and the side arm was
removed by flame sealing. The stopcock to the dynamic
vacuum was closed and the contents of the ampule(s) were
allowed to mix. The reaction was stirred by magnetic stir¬
ring for 3 days with periodic degassing. The precipitated
product and the tetrahydrofuran were decanted into a
receiving flask and flame sealed.
General Procedure for Dual-Anionic Polymerization
In a typical experiment using vacuum line and breakseal
techniques, 5 ml (100 mmoles) of ethylene oxide is vacuum
transferred into a 250-ml reaction vessel, at dry ice/iso¬
propanol temperature, containing a magnetic stirbar and
having attached ampules containing 1) 0.04 moles (2.5 ml) of
pivalolactone and 2) 0.005 moles 16 in 25 ml of tetrahydro¬
furan. The contents of the ampules are allowed to mix in
the reaction vessel, magnetic stirring is begun, and the
reaction temperature is maintained at 5°C by a constant
temperature bath. The reaction is given a static argon
atmosphere with a valve to release any sudden pressure.
After two days, the reaction vessel is evacuated to remove
tetrahydrofuran and any unreacted pivalolactone and ethylene
oxide. The product is isolated by hydrolysis, extraction
with methylene chloride, and precipitation in diethyl ether.

90
General Procedure for Sequential Addition Polymerization
In a typical experiment using vacuum line and breakseal
techniques, 10 ml (200 mmoles) of ethylene oxide is vacuum
transferred into a 250-ml reaction vessel containing a
magnetic stirbar and having an attached ampule containing 10
mmoles of 16 in 25 ml of tetrahydrofuran. The contents of
the ampule is mixed in the reaction vessel, magnetic
stirring is begun, and the reaction temperature is main¬
tained at 5°C by a constant temperature bath. The reaction
is given a static argon atmosphere open to a mineral oil
bubbler to release any sudden pressure. After two to three
days, the reaction vessel is evacuated to remove tetrahydro¬
furan and any unreacted ethylene oxide. The reaction vessel
is removed from the vacuum line, and the solid residue is
dissolved in water, acidified with dilute hydrochloric acid,
and extracted with four 25-ml portions of methylene chlor¬
ide. The methylene chloride extracts are combined, dried
over magnesium sulfate, and added to 500 g of cold diethyl
ether, precipitating polyether 17.
1 g of 17 is dissolved in methanol and titrated with
0.01 N potassium hydroxide in methanol with phenolphthalein
as an indicator. The solution is then rotovapped and the
residue, 18 dried in a drying pistol. Under argon, the salt
18 is reacted with pivalolactone in a molar ratio based upon
the amount of base needed in the titration, in 25 ml of dry
tetrahydrofuran. After 1 day, the reaction is evacuated to
remove tetrahydrofuran and unreacted pivalolactone.

91
Methylene chloride is added to dissolve as much of the
residue as possible. The resulting solution is shaken with
3 N hydrochloric acid and separated. The (OE)n-(PVL)m
telechelomer is isolated by precipitation in diethyl ether
or by evaporation of the methylene chloride solvent.
General Procedure for Alanine-Mediated Step Polymerization
The telechelomer and an equal molar amount of d,l-
alanine are placed in a three-necked polymerization reactor
fitted with mechanical stirrer, argon/vacuum inlet, and
syringe inlet with stopcock. The flask is evacuated and
maintained at a slightly elevated temperature to dry the
contents. Then the flask is given an argon atmosphere and
heated to 200°C by a salt bath. After the telechelomer
melts, mechanical stirring is begun, and the reaction
mixture is stirred for 1 hour. The flask is evacuated for
1/2 hour at 200°C to remove any unreacted d,1-alanine. One
mole percent titanium tetrabutoxide is added by syringe to
the reaction, and the reaction temperature is slowly
increased to 250°C over a period of 1 hour. Then, vacuum is
applied at 250°C for 1/2 hour. The reaction is allowed to
cool, and the resulting product is dissolved in methylene
chloride—or dissolved in boiling N,N-dimethylformamide and
cooled—and added to a large volume of diethyl ether. The
product is isolated by filtration and dried in a vacuum
desiccator

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APPENDIX
DECLARE SUB CalPlot (M!, B!, y!(), X!(), Stand$(), Ans%)
DECLARE FUNCTION SelectFile% (Ext$)
DECLARE FUNCTION FCount% (Ext$)
DECLARE FUNCTION DOSError% ()
***********************************************************
' SEC Programs BASIC program listing. It should be *
• compiled with Microsoft QuickBASIC compiler version 4.5 *
1 and linked with SEC.LIB, which is a library containing *
MetraByte DASCONl.OBJ and some assembly language *
routines from Cresent Software QuickPak Professional. *
*
SEC Programs is the data collection and analysis *
program for the Polymer Floor SEC instrument at the *
University of Florida. *
*
Written by J. C. Matayabas, Jr. *
**********************************************************
***********************************************************
' Part I. Program Initialization. *
***********************************************************
DIM TData AS INTEGER, RunLength AS INTEGER
DIM MaxSignal AS INTEGER, Counter AS INTEGER
DIM chnl AS INTEGER, Dat(2404) AS INTEGER
DIM FlowRate AS SINGLE, D1 AS SINGLE, D2 AS SINGLE DIM
StandF(lO) AS STRING, DIM RunEnd AS INTEGER
DIM Area AS SINGLE, Surnl AS SINGLE, Sum2 AS SINGLE
DIM Mp AS SINGLE, Mn AS SINGLE, Mw AS SINGLE
DIM CalFile AS STRING, XXI AS INTEGER, XX2 AS INTEGER
DIM XI AS INTEGER, X2 AS INTEGER, YY1 AS INTEGER
DIM YY2 AS INTEGER, Y1 AS INTEGER, Y2 AS INTEGER
DIM FileName AS STRING, FileSpec AS STRING, AnyKey AS STRING
DIM MwMn AS SINGLE, Peak AS INTEGER, Valley AS INTEGER
DIM Number1 AS INTEGER, Number2 AS INTEGER, Number AS SINGLE
DIM Dio(8) AS INTEGER, Md AS INTEGER, Ch AS INTEGER
DIM BasAdr AS INTEGER, Sigma AS SINGLE, LogMp(lO) AS SINGLE
DIM VMp(lO) AS SINGLE, Slope AS SINGLE, Intercept AS SINGLE
DIM Correlation AS SINGLE
DIM SHARED Stand$(10), Flag AS INTEGER
DIM Dat2Max AS INTEGER, Dat2Min AS INTEGER, Chnl2 AS INTEGER
DIM Dat2(2404) AS INTEGER, Mass AS SINGLE
DIM SData(607) AS INTEGER
DEFINT N: SCREEN 0: CLS
FlowRate =1/60: RunLength = 2400: Chnl = 0: Chnl2 = 4
MaxSignal = 2000: CalFile = "**"
96

97
***********************************************************
' Part II. Setup and Run Routine. Main Menu. *
i**********************************************************
Setup:
ERASE Dat, Dat2: CLS 0: SCREEN 2: VIEW PRINT 1 TO 25
LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition"
PRINT USING "Flow: #.# ml/min Run: ##.# ml";_
FlowRate * 60; RunLength * FlowRate;
PRINT USING " Y-Max: #### mV Chnl: #"; MaxSignal; Chnl;
IF Chnl2 <> 4 THEN PRINT USING #"; Chnl2;
PRINT USING " Cal: CalFile;
VIEW (20, 20)-(620, 172), , 7
Numberl = -.15 * MaxSignal: WINDOW (0, Numberl)-(RunLength,
MaxSignal)
SELECT CASE RunLength * FlowRate
CASE IS > 160
Number = 40 / FlowRate
CASE IS > 80
Number = 20 / FlowRate
CASE IS > 40
Number = 10 / FlowRate
CASE IS > 20
Number = 5 / FlowRate
CASE IS > 10
Number = 2 / FlowRate
CASE ELSE
Number = 1 / FlowRate
END SELECT
FOR Counter = 0 TO RunLength STEP Number
LINE (Counter, Numberl)-(Counter, Numberl *5/6)
Number2 = ((Counter / (RunLength * 8)) * 600) + 2
LOCATE 23, Number2: PRINT USING "##"; Counter * FlowRate
NEXT Counter
LOCATE 23, 5: PRINT "ml": VIEW PRINT 24 TO 25
PRINT " = Recall Cal Curve = Create Cal Curve
= Recall File"
PRINT " = MultiPlot

= Change Parameters
= Run Sample = Exit";
MainMenu:
SELECT CASE UCASE$(INPUT$(1))
' Exit Chosen.
CASE CHR$(27)
END
1 Recall Cal Curve chosen.
CASE "B"
Ans% = SelectFile%(".CAL"): IF Ans% <> 1 THEN GOTO Setup
CalFile = Stand$(l)
OPEN "B:" + CalFile + ".CAL" FOR INPUT AS #1
INPUT #1, DI, D2: CLOSE #1: GOTO SetUp
' Create Cal Curve chosen.
CASE "C"
Ans% = SelectFile%(".STD"): IF Ans% = 0 THEN GOTO SetUp
IF Ans% < 2 THEN
CLS : PLAY "L32ECEC"

98
PRINT "You Must Select 2 or More Files."
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): GOTO Setup
END IF
PRINT "Calculating, Please Wait...";
FOR N = 1 TO Ans%
ERASE SData: StandF(N) = "B:\" + Stand$(N) + ".STD"
CALL QBLoad(StandF(N), SEG SData(0))
FlowRate = SData(601) / 6000
Mp = SData(602): Mp = Mp * 30000 + SData(603)
MwMn = SData(604) / 100: Peak = SData(605)
LogMp(N) = LOG(Mp): VMp(N) = Peak * FlowRate
NEXT N
Ex = 0: Exx =0: Ey = 0: Eyy = 0: Exy = 0
FOR N = 1 TO Ans%
Ex = Ex + VMp(N): EXX = EXX + VMp(N) * 2
Ey = Ey + LogMp(N): Eyy = Eyy + LogMp(N) ~ 2
Exy = Exy + VMp(N) * LogMp(N)
NEXT N
SSx = Exx - (Ex ~ 2 / Ans%): SSy = Eyy - (Ey * 2 / Ans%)
SSxy = Exy - (Ex * Ey / Ans%): Slope = SSxy / SSx
Intercept = (Ey / Ans%) - (Slope * (Ex / Ans%))
Correlation = SSxy / SQR(SSx * SSy)
IF Correlation < 0 THEN Correlation = -Correlation
D1 = EXP(Intercept): D2 = -Slope
CLS : PRINT "Calibration Results:": PRINT
PRINT "Standard Mp Mw/Mn Sigma LnMp Vmax"
H
FOR N = 1 TO Ans%
ERASE SData: CALL QBLoad(StandF(N), SEG SData(O))
FlowRate = SData(601) / 6000
Mp = SData(602): Mp = Mp * 30000 + SData(603)
MwMn = SData(604) / 100: Peak = SData(605): XI = SData(606)
X2 = SData(607): Area = 0: Suml = 0: Sum2 = 0
FOR Counter = XI TO X2
Numberl = Counter - XI: TData = SData(Numberl)
Area = Area + TData: Mass = D1 * EXP(-D2 * Counter *_
FlowRate)
Suml = Suml + (TData / Mass)
Sum2 = Sum2 + (TData * Mass)
NEXT Counter
CLOSE #1: Mn = Area / Suml: Mw = Sum2 / Area
Sigma = Mw / Mn: Sigma = Sigma / MwMn
IF Sigma <= 1 THEN Sigma = 0 ELSE Sigma = SQR(LOG(Sigma))
Sigma = Sigma / D2
PRINT USING »\ \ ######## ##.##"; Stand$(N); Mp;_
MwMn;
PRINT USING " #.### ###.## ###.##"; Sigma; LogMp(N);_
VMp(N)
NEXT N
PRINT : PRINT USING "Slope = ##.###"; -D2
PRINT USING "Intercept = ###.##"; Intercept
PRINT USING "Correlation = #.####"; Correlation

99
IF D2 <= 0 OR Correlation < .9 THEN
PLAY "L32ECEC": PRINT
PRINT "One or More of Your Standard Files Do Not Correlate."
PRINT "This is Not a Valid Calibration. Please Recheck Your_
Data."
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): GOTO Setup
END IF
IF Correlation < .99 THEN
PLAY "L32ECEC": PRINT
PRINT "The Correlation is Poor, and This May Not Be a Valid_
Calibration."
PRINT "The Calibration Range May be Too Large. Please_
Recheck Your Data."
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): PRINT
END IF
PRINT : PRINT "Press Any Key to View Graph...";
AnyKey = INPUT$(1)
CALL CalPlot(-D2, Intercept, LogMp(), VMp(), Stand$(), Ans%)
VIEW PRINT 24 TO 25: CLS 2
PRINT "Do you want to save this calibration curve (Y/N)? ";
AnyKey = UCASE$(INPUT$(1)): PRINT AnyKey
IF AnyKey = "N" THEN GOTO SetUp
PRINT "Saving Calibration Curve..."
Ext$ = ".CAL": GOSUB GetName: OPEN FileSpec FOR OUTPUT AS #1
WRITE #1, DI, D2: CLOSE #1: CalFile = FileName
VIEW PRINT 2 TO 2: CLS 2
LOCATE 2, 28: PRINT USING "Calibration Curve FileName;
VIEW PRINT 24 TO 25: CLS 2
PRINT "Press

to Plot or Any Other Key to Continue...";
AnyKey = UCASE$(INPUT$(1))
IF AnyKey = "P" THEN
CLS 2: PRINT USING " Slope = ##.###"; -D2;
PRINT USING " Intercept = ###.##"; Intercept;
PRINT USING " Correlation = ##.####"; Correlation;
CALL ScrnDump("", 1, 0)
END IF
GOTO SetUp
' Recall File chosen.
CASE "F"
Ans% = SelectFile%(".SEC"): IF Ans% = 0 THEN GOTO Setup
FileName = Stand$(l): FileSpec = "B:" + FileName + ".SEC"
CLS 2: PRINT "Recalling File. Please Wait...";
CALL QBLoad(FileSpec, SEG Dat(0))
FlowRate = Dat(2401) / 6000: RunEnd = Dat(2402)
DatMax = Dat(2403): DatMin = Dat(2404)
Numberl = .1 * Dat(DatMax): YY2 = Dat(DatMax) + Numberl
YY1 = Dat(DatMin) - Numberl: IF YY1 >= 0 THEN YY1 = -Numberl
XXI = 0: XX2 = RunEnd: GOSUB ReDraw
CASE "M"
Ans% = SelectFile%(".MPT"): IF Ans% = 0 THEN GOTO Setup
PRINT "Select Volume Range (ml):"
INPUT "Enter Volume Minimum: ", XXI

100
INPUT "Enter Volume Maximum: ", XX2
IF XXI >= XX2 THEN PLAY "L32ECEC": GOTO SetUp
CLS 0: SCREEN 2: VIEW PRINT 1 TO 25
LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition"
VIEW (20, 20)-(620, 172), , 7
WINDOW (XXI, -100)-(XX2, 1100)
SELECT CASE (XX2 - XXI)
CASE IS >= 20
Number1 = 5
CASE IS >= 10
Number1 = 2
CASE ELSE
Number1 = 1
END SELECT
FOR Counter = XXI TO XX2 STEP Number1
LINE (Counter, -100)-(Counter, -50)
N = ((Counter - XXI) / ((XX2 - XXI) * 8) * 600) + 2
LOCATE 23, N: PRINT USING "##"; Counter;
NEXT Counter
LOCATE 23, 5: PRINT "ml";
FOR Counter = 1 TO Ans%
FileSpec = "B:" + Stand$(Counter) + ".MPT"
OPEN FileSpec FOR INPUT AS #1
Peak = 0: INPUT #1, Volume, VData: PSET (Volume, VData)
DO UNTIL EOF(1)
INPUT #1, Volume, VData: LINE -(Volume, VData)
IF VData > Peak THEN Peak = VData: Number = Volume
LOOP
CLOSE #1
N = ((Number - XXI) / ((XX2 - XXI) * 8) * 600) + 2
IF N < 4 THEN N = 4 ELSE IF N > 76 THEN N = 76
LOCATE 4, N: PRINT USING Counter
NEXT Counter
LOCATE 2, 1
FOR Counter = 1 TO Ans%
IF Counter = 6 THEN LOCATE 24, 1
PRINT USING "##: & "; Counter; Stand$(Counter);
NEXT Counter
VIEW PRINT 24 TO 25
LOCATE 25, 1: PRINT "Press

to Print or Any Other Key to
Continue...";
AnyKey = UCASE$(INPUT$(1))
IF AnyKey = "P" THEN CLS 2: CALL ScrnDump("", 1, 0)
GOTO Setup
' Change Parameters chosen.
CASE "P"
CLS 2: INPUT "Enter flow rate (ml/min): ", Number
IF Number <> 0 THEN FlowRate = Number / 60
INPUT "Enter length of run (ml): ", Number
Number = Number / FlowRate
IF Number >= 100 AND Number <= 2400 THEN RunLength = Number
INPUT "Enter maximum signal (100-2000 mV): ", Numberl
IF Numberl >= 100 AND Numberl <= 2000 THEN MaxSignal =
Numberl

101
SELECT CASE Chnl2
CASE 4
INPUT "Enter channel to moniter (0-3, 4=moniter 2 _
channels): ", Number1
IF Numberl <= 3 AND Numberl >= 0 THEN Chnl = Numberl
IF Numberl = 4 THEN
INPUT "Enter first channel to moniter (0-3): ", Numberl
IF Numberl <= 3 AND Numberl >= 0 THEN Chnl = Numberl
INPUT "Enter second channel to moniter (0-3, 4=disable): ",
Numberl
IF Numberl <= 3 AND Numberl >= 0 THEN Chnl2 = Numberl_
ELSE Chnl2 = 4
IF Chnl = Chnl2 THEN Chnl2 = 4
END IF
CASE ELSE
INPUT "Enter first channel to moniter (0-3): ", Numberl
IF Numberl <= 3 AND Numberl >= 0 THEN Chnl = Numberl
INPUT "Enter second channel to moniter (0-3, 4=disable):_
", Numberl
IF Numberl <= 3 AND Numberl >= 0 THEN Chnl2 = Numberl ELSE_
Chnl2 = 4
IF Chnl = Chnl2 THEN Chnl2 = 4
END SELECT
GOTO Setup
' Run Sample chosen.
CASE "R"
CLS 2: PRINT "Press Any Key to Start Run...";
AnyKey = INPUT$(1): CLS 2
PRINT "Press to Stop Run..."
Flag = 0: Ch = 5: Md = 3: BasAdr = 800
DatMax = 0: DatMin = 0
CALL DASCONl(Md, Ch, Dio(0), Dio(l), BasAdr)
FOR Counter = 0 TO RunLength
AnyKey = INKEY$: IF AnyKey = CHR$(27) THEN EXIT FOR
Md = 6
DO: CALL DASCON1(Md, Ch, Dio(0), Dio(l), BasAdr)
LOOP WHILE Dio(8) = 0
Dat(Counter) = INT(Dio(Chnl) * .5)
IF Dat(Counter) > 2000 THEN PLAY "L32EC": Dat(Counter) =_
2000: Flag = 1
IF Dat(Counter) < -2000 THEN PLAY "L32EC": Dat(Counter) =_
-2000: Flag = 1
IF Dat(Counter) > Dat(DatMax) THEN DatMax = Counter
IF Dat(Counter) < Dat(DatMin) THEN DatMin = Counter
IF Counter > 0 THEN LINE ((Counter - 1), Dat(Counter -_
1))-(Counter, Dat(Counter))
LOCATE 25, 1
PRINT USING "Chnl # ##.## ml"; Chnl; Counter * FlowRate;
PRINT USING ", #### mV"; Dat(Counter);
IF Chnl2 <> 4 THEN
Dat2(Counter) = INT(Dio(Chnl2) * .5)
IF Dat2(Counter) > 2000 THEN PLAY "L32EC": Dat2(Counter) =_
2000: Flag = 1

102
IF Dat2(Counter) < -2000 THEN PLAY "L32EC": Dat2(Counter) =
-2000: Flag = 1
IF Dat2(Counter) > Dat2(Dat2Max) THEN Dat2Max = Counter
IF Dat2(Counter) < Dat2(Dat2Min) THEN Dat2Min = Counter
IF Counter > 0 THEN LINE ((Counter - 1), Dat2(Counter -_
1))-(Counter, Dat2(Counter)), 15
PRINT USING " Chnl # ##.## ml"; Chnl2; Counter *_
FlowRate;
PRINT USING ", #### mV"; Dat2(Counter);
END IF
NEXT Counter
RunEnd = Counter - 1: Md = 4
CALL DASCONl(Md, Ch, Dio(0), Dio(l), BasAdr)
CLS 2: PRINT "Data Run Has Ended";
IF Flag = 1 THEN
PLAY "L32ECEC": CLS 2
PRINT "A Portion of This Run Was Off-Scale."
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): CLS 2
END IF
IF Chnl2 <> 4 THEN
CLS 2: PRINT USING "Saving Data From Channel # ..."; Chnl2
Ext$ = ".SEC": GOSUB GetName
Dat2(2401) = FlowRate * 6000: Dat2(2402) = RunEnd
Dat2(2403) = DatMax: Dat(2404) = Dat2Min
CALL QBSave(FileSpec, SEG Dat2(0), 4810)
CLS 2: PRINT USING "Data File Saved as &.SEC"; FileName
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1)
END IF
CLS 2: PRINT USING "Saving Data From Channel # ..."; Chnl
Ext$ = ".SEC": GOSUB GetName
Dat(2401) = FlowRate * 6000: Dat(2402) = RunEnd
Dat(2403) = DatMax: Dat(2404) = DatMin
CALL QBSave(FileSpec, SEG Dat(0), 4810)
CLS 2: PRINT USING "Data File Saved as &.SEC"; FileName
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): Numberl = .1 * Dat(DatMax)
YY1 = Dat(DatMin) - Numberl: YY2 = Dat(DatMax) + Numberl
IF YY1 >= 0 THEN YY1 = -Numberl
XXI = 0: XX2 = RunEnd: GOSUB ReDraw
' Required Dummy Selection.
CASE ELSE
GOTO MainMenu
• **********************************************************
1 Part III. Data Analysis Routine. Analysis Menu. *
• **********************************************************
Analysis:
PRINT
PRINT

=
" =
Plot"
Calculate
= Standard
= Export
PRINT
" =
Rescale
= Setup & Run
= Restore
= Exit";

103
SELECT CASE UCASE$(INPUT$(1))
' Exit chosen.
CASE CHR$(27)
END
' Calculate chosen.
CASE "C"
IF CalFile = "**" THEN
PLAY "L32ECEC": PRINT
PRINT "You Must First Recall/Create a Calibration File."
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): GOTO Analysis
END IF
GOSUB Cursors: CLS 2
INPUT "Enter the Value of Sigma: ", Sigma
PRINT : PRINT "Use Universal Calibration (Y/N)? ";
AnyKey = UCASE$(INPUT$(1)): PRINT AnyKey
IF AnyKey = "Y" THEN
INPUT "Enter K1 (Standard): K1
INPUT "Enter A1 (Standard): "; A1
INPUT "Enter K2 (Sample): "; K2
INPUT "Enter A2 (Sample): "; A2
Cl = (K1 / K2) * (1 / (A2 + 1)): C2 = (A1 + 1) / (A2 + 1)
ELSE
Cl = 0: C2 = 0
END IF
CLS 2: PRINT "Calculating, Please Wait...";
Area = 0: Suml = 0: Sum2 = 0
Slope = (Dat(XI) - Dat(X2)) / (XI - X2)
FOR Counter = XI TO X2
TData = Dat(Counter) - (Dat(Xl) + Slope * (Counter - XI))
IF TData < 0 THEN TData = 0
Area = Area + TData
Mass = D1 * EXP(-D2 * FlowRate * Counter)
IF Cl <> 0 THEN Mass = Cl * Mass “ C2
Suml = Suml + (TData / Mass)
Sum2 = Sum2 + (TData * Mass)
NEXT Counter
Mp = D1 * EXP(-D2 * FlowRate * Peak)
IF Cl <> 0 THEN Mp = Cl * Mp C2
Number = (D2 * Sigma) ~ 2
Mn = EXP(Number / 2) * Area / Suml
Mw = EXP(Number / -2) * Sum2 / Area: MwMn = Mw / Mn
VIEW PRINT 5 TO 10
LOCATE
5,
5:
PRINT
USING
" Mp = ########";
Mp;
LOCATE
6,
5:
PRINT
USING
" Mw = ########";
Mw;
LOCATE
7,
5:
PRINT
USING
" Mn = ########";
Mn;
LOCATE
8,
5:
PRINT
USING
"Mw/Mn = #.##";
MwMn;
LOCATE
9,
5:
PRINT
USING
" Area = ########";
Area;
VIEW PRINT 24 TO 25
' Save as Standard chosen.
CASE "D"
GOSUB Cursors
IF X2 - XI > 600 THEN
CLS 2: PLAY "L32ECEC": PRINT "Error - Region too Large."

104
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): GOSUB ReDraw: GOTO Analysis
END IF
CLS 2: DO: INPUT "Enter Mp: Mp: LOOP WHILE Mp <= 0
DO: INPUT "Enter Mw/Mn: MwMn
LOOP WHILE MwMn <= 0 OR MwMn > 5
PRINT "Saving Standard File...": Ext$ = ".STD"
GOSUB GetName
Slope = (Dat(XI) - Dat(X2)) / (XI - X2)
FOR Counter = XI TO X2
TData = Dat(Counter) - (Dat(Xl) + Slope * (Counter - XI))
IF TData < 0 THEN TData = 0
Numberl = Counter - XI: SData(Number1) = TData
NEXT Counter
SData(601) = FlowRate * 6000: SData(604) = MwMn * 100
SData(602) = (Mp / 30000) - .5: SData(603) = Mp MOD 30000
SData(605) = Peak: SData(606) = XI: SData(607) = X2
CALL QBSave(FileSpec, SEG SData(0) , 1216)
CLS 2
PRINT USING "Standard File Saved as FileName; Ext$
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1)
CASE "E"
GOSUB Cursors: CLS 2: PRINT "Saving as ASCII File..."
Slope = (Dat(XI) - Dat(X2)) / (XI - X2): N = 0
FOR Counter = XI TO X2
TData = Dat(Counter) - (Dat(Xl) + Slope * (Counter - XI))
IF TData > N THEN N = TData
NEXT Counter
Ext$ = ".MPT": GOSUB GetName
ON ERROR GOTO FlagError: OPEN FileSpec FOR OUTPUT AS #1
FOR Counter = XI TO X2
TData = Dat(Counter) - (Dat(Xl) + Slope * (Counter - XI))
IF TData < 0 THEN TData = 0
TData = (TData / N) * 1000 .
WRITE #1, Counter * FlowRate, TData
NEXT Counter
ON ERROR GOTO 0: CLOSE #1
CLS 2: PRINT USING "File Saved as FileName; Ext$
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1)
' Plot chosen.
CASE "P"
CLS 2: PRINT "Plotting, Please Wait...";
CALL ScrnDump("", 1, 0)
' Restore chosen.
CASE "T"
Numberl = .1 * Dat(DatMax): YY2 = Dat(DatMax) + Numberl
YY1 = Dat(DatMin) - Numberl: IF YY1 >= 0 THEN YY1 = -Numberl
XXI = 0: XX2 = RunEnd: GOSUB ReDraw
' Setup & Run chosen.
CASE "S"
GOTO Setup
' Rescale chosen.

105
CASE "R"
CLS 2
PRINT " = Type in Values = Use Arrow Keys =
Exit";
SELECT CASE UCASE$(INPUT$(1))
CASE "T"
CLS 2
PRINT USING "Current X-min = ##.## ml "; XXI * FlowRate
INPUT "Enter New Value: ", Number
XI = Number / FlowRate
PRINT
USING
"Current X-max
= ##.## ml"
; XX2
INPUT
"Enter
New Value: ",
Number
X2 = Number
/ FlowRate
PRINT
USING
"Current Y-min
= ####
mV";
YYl
INPUT
"Enter
New Value: ",
Yl
PRINT
USING
"Current Y-max
= ####
mV";
YY2
INPUT
"Enter
New Value: ",
Y2
CASE "R"
GOSUB Cursors
CASE ELSE
GOTO Analysis
END SELECT
IF XI = X2 OR Y1 = Y2 THEN
PLAY "L32ECEC": CLS 2: PRINT "Error in Rescaling"
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): GOTO Analysis
END IF
IF Y1 > 2200 THEN Y1 = 2200: IF Y2 < -2200 THEN Y2 = -2200
XXI = XI: XX2 = X2: YY1 = Yl: YY2 = Y2: GOSUB ReDraw
' Required Dummy selection.
CASE ELSE
GOTO Analysis
END SELECT
GOTO Analysis
END
i**********************************************************
1 Part IV. Subroutines. *
• **********************************************************
GetName:
DO
INPUT "Enter File Name Using 8 Characters or Less: ",_
FileName
LOOP WHILE INSTR(FileName, ».") OR INSTR(FileName, ":")
IF FileName = "" THEN FileName = "TEMP"
FileName = UCASE$(FileName)
FileSpec = "B:" + FileName + Ext$
Numberl = FCount%(FileSpec)
IF DOSError THEN
CLS 2: PLAY "L32ECEC": PRINT "Error in Reading Data Disk."
PRINT "Check Disk Drive B: and Press Any Key to_
Continue...";
AnyKey = INPUT$(1): GOTO GetName
END IF

106
IF Number1 > 0 THEN
IF FileName = "TEMP" THEN KILL FileSpec: RETURN
PLAY "L32ECEC": PRINT
PRINT USING "File && Already Exhists."; FileName; Ext$
PRINT "Overwrite it (Y/N)? ";
AnyKey = UCASE$(INPUT$(1)): PRINT AnyKey;
IF AnyKey = "Y" THEN KILL FileSpec ELSE CLS 2: GOTO GetName
END IF
RETURN
ReDraw:
CLS 0: SCREEN 2: VIEW PRINT 1 TO 2
LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition"
LOCATE 2, 34: PRINT USING "File: FileName;
VIEW (20, 20)-(620, 172), , 7
WINDOW (XXI, YY1)-(XX2, YY2)
VIEW PRINT 23 TO 23
SELECT CASE (XX2 - XXI) * FlowRate
CASE IS > 160
Number = 40 / FlowRate
CASE IS > 80
Number = 20 / FlowRate
CASE IS > 40
Number = 10 / FlowRate
CASE IS > 20
Number = 5 / FlowRate
CASE IS > 10
Number = 2 / FlowRate
CASE ELSE
Number = 1 / FlowRate
END SELECT
N = YY1 * 5 / 6: IF N >= 0 THEN N = -.05 * YY2
FOR Counter = 0 TO XX2 STEP Number
IF Counter >= XXI THEN
LINE (Counter, YY1)-(Counter, N)
Number1 = ((Counter - XXI) / ((XX2 - XXI) * 8) * 600) + 2
LOCATE 23, Numberl: PRINT USING "##"; Counter * FlowRate;
END IF
NEXT Counter
LOCATE 23, 5: PRINT "ml";
PSET (XXI, Dat(XXI))
FOR Counter = (XXI + 1) TO XX2
LINE -(Counter, Dat(Counter))
NEXT Counter
VIEW PRINT 24 TO 25
RETURN
Cursors:
CLS 2
PRINT "Use Arrow Keys to Position Cursors and Press ."
XI = XXI: X2 = XX2: Y1 = YY1: Y2 = YY2
Numberl = 128: Number2 = 1: YYY = .05 * (YY2 - YY1)
DO: LINE (XI, Dat(XI) - YYY)-(XI, Dat(XI) + YYY)
LINE (X2, Dat(X2) - YYY)-(X2, Dat(X2) + YYY)
LOCATE 25, 1

107
PRINT USING "Left: ##.## ml, #### mV"; XI * FlowRate;_
Dat(XI);
PRINT USING " Right: ##.## ml, #### mV"; X2 * FlowRate;_
Dat(X2);
DO: AnyKey = INKEY$: LOOP UNTIL LEN(AnyKey) = 2
SELECT CASE ASC(MID$(AnyKey, 2))
CASE 80
IF Number1 > 1 THEN Number1 = Number1 / 2
CASE 72
IF Number1 < 512 THEN Number1 = Number1 * 2
CASE 75
IF Number2 = 1 AND XI >= Numberl THEN
LINE (XI, Dat(XI) - YYY)-(X1, Dat(Xl) + YYY), 0
FOR N = XI - 3 TO XI + 2
IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N_
+ D)
NEXT N
XI = XI - Numberl
END IF
IF Number2 = 2 AND X2 > Numberl AND X2 - Numberl > XI THEN
LINE (X2, Dat(X2) - YYY)-(X2, Dat(X2) + YYY), 0
FOR N = X2 - 3 TO X2 + 2
IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N_
+ 1))
NEXT N
X2 = X2 - Numberl
END IF
CASE 77
IF Number2 = 1 AND XI < XX2 - Numberl AND XI + Numberl < X2
THEN
LINE (XI, Dat(XI) - YYY)-(XI, Dat(Xl) + YYY), 0
FOR N = XI - 3 TO XI + 2
IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N_
+ D)
NEXT N
XI = XI + Numberl
END IF
IF Number2 = 2 AND X2 <= XX2 - Numberl THEN
LINE (X2, Dat(X2) - YYY)-(X2, Dat(X2) + YYY), 0
FOR N = X2 - 3 TO X2 + 2
IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N_
+ U)
NEXT N
X2 = X2 + Numberl
END IF
CASE 71
IF Number2 = 1 THEN Number2 = 2 ELSE Number2 = 1
CASE 79
EXIT DO
CASE ELSE
END SELECT
LOOP
LINE (XI, Dat(XI) - YYY)-(XI, Dat(Xl) + YYY), 0
FOR N = XI - 3 TO XI + 2

108
IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N_
+ 1))
NEXT N
LINE (X2, Dat(X2) - YYY)-(X2, Dat(X2) + YYY), 0
FOR N = X2 - 3 TO X2 + 2
IF N > XXI AND N < XX2 THEN LINE (N, Dat(N))-(N + 1, Dat(N_
+ D)
NEXT N
Peak = XI: Valley = XI
FOR Counter = XI + 1 TO X2
IF Dat(Counter) > Dat(Peak) THEN Peak = Counter
IF Dat(Counter) < Dat(Valley) THEN Valley = Counter
NEXT Counter
Numberl = .1 * Dat(Peak): Y2 = Dat(Peak) + Numberl
Y1 = Dat(Valley) - Numberl: IF Y1 >= 0 THEN Y1 = -Numberl
RETURN
FlagError:
CLS 2
PLAY "L32ECEC": PRINT "Error in Saving File, Disk May be_
Full."
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1)
RESUME Setup
SUB CalPlot (M, B, y(), X(), Stand$(), Ans%)
***********************************************************
' CalPlot is a compiled subroutine that plots the graph *
' graph of a linear function with automatic selection of *
' x and y ranges. *
***********************************************************
CLS 0: SCREEN 2
WINDOW SCREEN (0, .5)-(80, 25)
LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition"
LOCATE 2, 25: PRINT " Calibration"
YMIN = y(1)
FOR N = 1 TO Ans%
IF y(N) < YMIN THEN YMIN = y(N)
NEXT N
YMIN = INT(YMIN - .5): XMIN = X(l)
FOR N = 1 TO Ans%
IF X(N) < XMIN THEN XMIN = X(N)
NEXT N
XMIN = INT(XMIN - .5)
Repeat:
Yint = M * XMIN + B
IF Yint < YMIN THEN YMIN = INT(Yint - .5)
YMAX = INT(Yint + 1)
FOR N = 1 TO Ans%
IF YMAX < y(N) THEN YMAX = INT(y(N) + 1)
NEXT N
Xint = (YMIN - B) / M
IF Xint < XMIN THEN XMIN = INT(Xint - .5): GOTO Repeat
XMAX = INT(Xint + 1)
FOR N = 1 TO Ans%

109
IF XMAX < X(N) THEN XMAX = INT(X(N) + 1)
NEXT N
LINE (9, 3)-(77, 20) , , B
Ydelta = YMAX - YMIN: Yscale = 17 / Ydelta
IF Ydelta >= 10 THEN Ystep = 2 ELSE Ystep = 1
IF Ydelta >=20 THEN Ystep = 4
FOR N = 0 TO Ydelta STEP Ystep
YY = 20 - N * Yscale: LINE (8, YY)-(9, YY)
LOCATE INT(YY + .5), 6: PRINT USING YMIN + N
NEXT N
Xdelta = XMAX - XMIN: Xscale = 68 / Xdelta
IF Xdelta >= 10 THEN Xstep = 2 ELSE Xstep = 1
IF Xdelta >=20 THEN Xstep = 4
FOR N = 0 TO Xdelta STEP Xstep
XX = 9 + N * Xscale: LINE (XX, 20)-(XX, 21)
LOCATE 22, INT(XX): PRINT USING XMIN + N;
NEXT N
YYscale = 20 - (Yint - YMIN) * Yscale
XXscale = 9 + (Xint - XMIN) * Xscale
LINE (9, YYscale)-(XXscale, 20)
LOCATE 23, 35: PRINT "Volume (ml)"
LOCATE 12, 2: PRINT "InM"
FOR N = 1 TO Ans%
IX = 9 + (X(N) - XMIN) * Xscale
IY = 20 - (y(N) - YMIN) * Yscale
CIRCLE (IX, IY), .5
LOCATE INT(IY - 1), INT(IX + 4): PRINT UCASE$(Stand$(N))
NEXT N
END SUB
FUNCTION SelectFile% (Ext$)
• **********************************************************
SelectFile is a compiled funtion that returns the *
number of files selected from a directory menu of *
B:\*.Ext, where Ext is passed to SelectFile by the *
variable Ext$. *
The names of the files are passed to the main module *
by the shared array Stand$(). *
1 **********************************************************
DIM Item AS INTEGER, AnyKey AS STRING, Count AS INTEGER
DEFINT M-N
ERASE Stand$: CLS 0: SCREEN 0
LOCATE 1, 25: PRINT "SEC PROGRAMS Advanced Edition"
VIEW PRINT 3 TO 25
Spec$ = "B:\*" + Ext$: Count = FCount%(Spec$)
IF Count = 0 THEN
PLAY "L32ECEC"
PRINT USING "There Are no & Files on Data Disk."; Ext$
PRINT "Press Any Key to Continue...";
AnyKey = INPUT$(1): SelectFile% = 0: GOTO Done
END IF
DIM Text$(0 TO Count)
FOR N = 1 TO Count
Text$(N) = SPACE$(12)

110
NEXT N
Text$(0) = Spec$
CALL ReadFile(BYVAL VARPTR(Text$(0)))
FOR N = 1 TO Count
M = INSTR(Text$(N),
Text$(N) = MID$(Text$(N), 1, M - 1) + SPACE$(1)
NEXT N
IF Ext$ = ".STD" THEN
LOCATE 3, 19
PRINT "Select Standard Files Using the Arrow Keys."
ELSE
LOCATE 3, 16
PRINT "Select File to be Recalled Using the Arrow Keys."
END IF
LOCATE 4, 22: PRINT " = Select, = Done. "
VIEW PRINT 6 TO 25
Item = 1: Text$ = "": N = Count
Goes: LOCATE 6, 1
FOR M = 1 TO N
SELECT CASE INSTR(Text$, MKI$(M))
CASE 0
IF M = Item THEN COLOR 0, 7
PRINT SPACE$(1); Text$(M);
COLOR 7, 0: PRINT SPACE$(1),
CASE ELSE
IF M = Item THEN COLOR 0, 7
PRINT CHR$(26); Text$(M);
COLOR 7, 0: PRINT SPACE$(1),
END SELECT
NEXT M
LOCATE CSRLIN, POS(O), 0
PICKS:
DO: AnyKey = INKEY$: LOOP WHILE AnyKey = ""
SELECT CASE ASC(AnyKey)
CASE 13
a = INSTR(Text$, MKI$(Item))
IF a = 0 THEN
Text$ = Text$ + MKI$(Item)
ELSE
B$ = LEFT$(Text$, (a - 1))
C$ = RIGHT$(Text$, (LEN(Text$) - a))
Text$ = B$ + C$
END IF
IF Ext$ <> ".STD" AND Ext$ <> ".MPT" THEN GOTO Winners
GOTO Goes
CASE 0
SELECT CASE ASC(MID$(AnyKey, 2))
CASE 79
GOTO Winners
CASE 75
IF Item = 1 THEN Item = N ELSE Item = Item - 1
GOTO Goes
CASE 77
IF Item = N THEN Item = 1 ELSE Item = Item + 1

Ill
GOTO Goes
CASE 72
IF N < 5 THEN GOTO PICKS
Item = Item - 5: IF Item <= 0 THEN Item = N + Item
GOTO Goes
CASE 80
IF N < 5 THEN GOTO PICKS
Item = Item +5: IF Item > N THEN Item = Item - N
GOTO Goes
CASE ELSE
GOTO PICKS
END SELECT
CASE ELSE
GOTO PICKS
END SELECT
Winners: M = 1
FOR a = 1 TO N
IF INSTR(Text$, MKI$(a)) THEN Stand$(M) = RTRIM$(Text$(a))
M = M + 1
IF M = 11 THEN EXIT FOR
NEXT a
SelectFile% = M - 1: VIEW PRINT 3 TO 25: CLS 2
Done:
END FUNCTION

BIOGRAPHICAL SKETCH
When James Christopher Matayabas, Jr.—Chris to his
family and friends—was born on June 23, 1961, his family
lived in Frankfurt, West Germany, where his father was
stationed while serving in the United States Air Force.
After his father retired in 1974, his family settled in
Swannanoa, North Carolina. From 1975 to 1979, Chris
attended Charles D. Owen High School, where he was active in
athletics and student organizations. In June, 1979, he
graduated with honors.
In August, 1979, Chris entered the University of North
Carolina at Asheville (UNC-A). He began playing volleyball
for the USVBA-sponsored Asheville Volleyball Club and
working as a student assistant for the Mossbauer Effect Data
Center. Chris participated in organoantimony research under
the guidance of Dr. Leo A. Bares. In the summer of 1982,
Chris travelled to the Netherlands, where he worked with
organoantimony complexes under the supervision of Dr. Harry
K. Meinema of the Organisch Chemisch Universitaat, TNO.
Having been self-supporting since 1979, Chris began fulltime
employment and attended school part-time in 1983. He
graduated from UNC-A with a Bachelor of Science degree with
a major in chemistry in May, 1985, while teaching at Griffin
School.
112

113
On July 27, 1985, Chris was happily married to Deborah
W. Weeks, mother of Joseph Johnson, age 6.
In August, 1985, Chris and his new family moved to
Gainesville, Florida, where Chris began graduate school at
the University of Florida. He was awarded the "First Year
Graduate Student In Organic Chemistry With the Highest Grade
Point Average" and invited into the Phi Kappa Phi Honor
Society in August, 1986. Chris chose Dr. Kenneth B. Wagener
to be his research director and began research in polymer
chemistry.
In December, 1987, Chris was awarded the degree of
Master of Science, and he presented his thesis as a finalist
in the Sherwin-Williams Student Award in Applied Polymer
Science competition at the Fall, 1988, National American
Chemical Society Meeting.
Chris continued his graduate work, pursuing the degree
of Doctor of Philosophy. In October, 1990, while finishing
his dissertation, he accepted employment with Eastman
Chemical Company located in Kingsport, Tennessee.

I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
JA
\
Kenneth B. Wagener, Chairman
Associate Professor of Chemistry
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
William M. Jones
Distinguished Service Professor of
Chemistry
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree eff Doctor of Philosophy.
Russell S. Drago
Graduate Research Professor of
Chemistry
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of Philosophy.
Jobh A. Zoltewicz
Professor of Chemistry
I certify that I have read this study and that in my
opinion it conforms to acceptable standards of scholarly
presentation and is fully adequate, in scope and quality, as
a dissertation for the degree of Doctor of PhjJrO^ophy.
Eugene P. Goldberg
Professor of Materials Sciencfe^ and
Engineering

This dissertation was submitted to the Graduate Faculty
of the Department of Chemistry in the College of Liberal
Arts and Sciences and to the Graduate School and was
accepted as partial fulfillment of the requirements for the
degree of Doctor of Philosophy.
May 1991
Dean, Graduate School

UNIVERSITY OF FLORIDA
3 1262 08556 9985



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