Chain Polymerization of Ester Functionalized Monomers. Tao, Xie University of Massachusetts Amherst

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Chain Polymerization of Ester Functionalized Monomers. Tao, Xie University of Massachusetts Amherst University of Massachusetts Amherst ScholarWorks@UMass Amherst Doctoral Dissertations 1896 - February 2014 1-1-2001 Chain polymerization of ester functionalized monomers. Tao, Xie University of Massachusetts Amherst Follow this and additional works at: https://scholarworks.umass.edu/dissertations_1 Recommended Citation Xie, Tao,, "Chain polymerization of ester functionalized monomers." (2001). Doctoral Dissertations 1896 - February 2014. 1019. https://scholarworks.umass.edu/dissertations_1/1019 This Open Access Dissertation is brought to you for free and open access by ScholarWorks@UMass Amherst. It has been accepted for inclusion in Doctoral Dissertations 1896 - February 2014 by an authorized administrator of ScholarWorks@UMass Amherst. For more information, please contact [email protected]. 31E0bb D27S 6514 CHAIN POLYMERIZATION OF ESTER FUNCTIONALIZED MONOMERS A Dissertation Presented by TAO XIE Submitted to the Graduate School of the University of Massachusetts Amherst in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY September 2001 Polymer Science and Engineering © Copyright by Tao Xie 2001 All Rights Reserved CHAIN POLYMERIZATION OF ESTER FUNCTIONALIZED MONOMERS A Dissertation Presented by TAO XIE Approved as to style and content by: Jacques Penelle, Chair "^V^ Thomas J. McCarthy Department Head Polymer Science and Engineering ACKNOWLEDGMENTS I would like to thank my advisor, Prof. Jacques Penelle, for his thoughtful guidance and support throughout my Ph.D. research work. His knowledge and scientific attitude have benefited me the most. My committee members, Prof. Shaw L. Hsu and Prof. Paul M. Lahti, earned my gratitude for their helpful suggestions and criticisms, which I consider invaluable to the learning process in graduate school. During the course of this research, I have received generous help from people around me, in particular the members of CJJVIA lab at the University of Louvain in Belgium and members of the Penelle group at the University of Massachusetts. Mere words cannot adequately describe the benefit I have received from working in their intellectual environment. I owe particular gratitude to Herion Hugues whose initial work on the ring-opening polymerization of diethyl cyclopropane- 1,1-dicarboxylate was incorporated into Chapter 2 of this dissertation. I am especially indebted to Prof. Shaw L. Hsu and Dr. Andre Stolov for their collaboration in the second part of this thesis. My deepest appreciation is extended to all my friends for the memorable years inside and outside the lab in both Amherst and Louvain-la-Neuve in Belgium. Finally, I appreciate my parents for their love and support throughout the years. iv ABSTRACT CHAIN POLYMERIZATION OF ESTER FUNCTIONALIZED MONOMERS SEPTEMBER 2001 TAO XIE, B.S., ZHEJIANG UNIVERRSITY, P.R. CHINA M.S., ZHEJIANG UNIVERSITY, P.R. CHINA D.E.A., UNIVERSITY OF LOUVAIN, BELGIUM Ph.D., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Jacques Penelle The overall purpose of this dissertation is to develop new polymer materials containing ester functionalities. This document will be separated into two sections covering two synthetic research projects that I have worked on for my Ph.D. dissertation. Both projects involved chain polymerizations of ester- functionalized monomers. A key feature of this thesis was to gain an in-depth understanding of the individual chain polymerizations employed, namely, anionic ring-opening polymerization of dialkyl cyclopropane- 1,1-dicarboxylates and radical polymerization of multifunctional captodative monomers. Part I focuses on developing a new synthetic methodology based on anionic ring- opening polymerizations of cyclopropanes geminally substituted on the cycle. The goal was to obtain carbon-chain polymers with ester substituents located on every third-carbon atom of the backbone, a substitution pattern that cannot be achieved by any other synthetic method. Ester groups are chosen not only because of their electron- withdrawing nature that ensures enough activation but also because the structural properties in a very easy way. versatility offered by ester groups allows to tailor polymer v Conditions allowing this ring-opening polymerization to proceed in a living way arc identified. By taking advantage of the living character of the anionic polymerization, a control over the polymer end-groups, molecular weight and molecular weight distributiion of the polymers can be achieved. Tailoring the polymer properties is also possible by varying the ester groups. Chemical modification of the polymer offers another way to obtain new polymers such as polyelectrolyte having the same substitution pattern. In part II, a possible answer is proposed to the environmental issues the coating industry is currently facing which include the toxicity of acrylic monomers used and generation of volatile organic compounds during the process. New functionalized bis(a- substituted acrylate)s were developed that can be assumed non/less toxic based on previous literature. The new functionalities introduced in the monomers are crucial in affecting not only their reactivity toward the photopolymerization involved in the coating production but also some properties of the final coatings. Both of these aspects are covered in the research. vi TABLE OF CONTENTS Page ACKNOWLEDGEMENTS iv ABSTRACT ; v LIST OF TABLES xiii LIST OF FIGURES x i v LIST OF SCHEMES xv ii PART ONE: RING-OPENING POLYMERIZATION OF CYCLOPROPANE- 1 , 1 -DICARBOXYLATES CHAPTER 1 . INTRODUCTION 2 1.1 Background 2 1.2 General Goal and Specific Objectives of this Project 3 1.3 Design of a Synthetic Route to Polymers with Substitution Pattern d 7 1.3.1 Theoretical Considerations on the Ring-Opening Polymerization of Cyclopropanes 7 1.3.2 Polymerization of Cyclopropanes Reported in the Literature 10 1.3.2.1 Radical Polymerizations 10 1.3.2.2 Cationic Polymerizations 15 1.3.2.3 Coordination Polymerizations 17 1.3.2.4 Anionic Polymerizations 18 1 .4 Dissertation Plan 21 1.5 References 22 2. ANIONIC RING-OPENING POLYMERIZATION OF DIETHYL 25 CYCLOPROPANE- 1 , 1 -DICARBOXYLATE 2.1 Introduction 25 2.2 Experimental Part 26 2.2.1 Materials 26 2.2.2 Synthesis of Diethyl Cyclopropane- 1,1-Dicarboxylate 1 26 vii 2.2.3 Synthesis of Sodium Thiophenolate (PhSNa) ..27 2.2.4 Synthesis of Sodium Diethyl Methylmalonate (SDEM) 28 2.2.5 Polymerization Procedure 28 2.2.6 Measurements 29 2.3 Results and Discussion 29 2.3.1 Previous Study on the Ring-Opening Polymerization of 1 29 2.3.1.1 Synthesis of the Pure Monomer 1 29 2.3.1.2 Synthesis of the Initiator PhSNa 30 2.3.1.3 Polymerization Kinetics of 1 Initiated by Sodium Thiophenolate 31 2.3.1.4 Characterization of Poly(l) 34 2.3.2 Complementary Study on the Ring-Opening Polymerization in this Work 36 2.3.2.1 Initiator PhSNa 36 2.3.2.2 Other Factors Affecting the Polymerization of 1 38 2.4 Conclusions 42 2.5 References 43 3. ANIONIC RING-OPENING POLYMERIZATION OF DIISOPROPYL CYCLOPROPANE- 1 , 1 -DICARBOXYLATE 44 3.1 Introduction 44 3.2 Experimental Section 45 3.2.1 Materials 45 3.2.2 Synthesis of Potassium Thiophenolate (PhSK) 46 3.2.3 Synthesis of the Monomer 1 46 3.2.4 Polymerization Procedure 47 3.2.5 Measurements 48 3.3 Results 48 3.3.1 Polymerization Kinetics 48 3.3.2 Polymer Characterization 52 3.3.3 Physical Properties 55 3.4 Discussion 55 3.4. 1 Polymerization Mechanism 55 3.4.2 Influence of Temperature on the Polymerization 57 viii 3.4.3 Influence of the Counterion 58 3.4.4 End-Functionalization of Polymers 59 3.5 Conclusions 3.6 References 61 4. MOLECULAR WEIGHT DETERMINATION OF POLY(DIISOPROPYL CYCLOPROPANE- 1 , 1 -DICARBOXYLATE) 63 4.1 Introduction 53 4.2 Experimental Section 66 4.3 Results and Discussion 67 4.3.1 Experimental Design 67 l 4.3.2 Molecular Weight Measurements by H-NMR 68 4.3.3 Molecular Weight Measurements by GPC-MALLS 70 4.3.4 Molecular Weight Measurements by VPO 75 4.3.5 Molecular Weight Determination by MALDI-ToF 79 4.3.5.1 Effect of Cationization Reagents 80 4.3.5.2 Assignment of the MALDI-ToF Distributions 82 4.3.5.3 Poisson Distribution 87 4.4 Discussion 90 4.5 Conclusions 92 4.6 References 93 5. INFLUENCE OF SUBSTITUENTS ON THE ANIONIC RING-OPENING POLYMERIZATION OF CYCLOPROPANE- 1,1 -DICARBOXYLATES 95 5.1 Introduction 95 5.2 Experimental Part 96 5.2.1 Materials 96 5.2.2 Measurements 97 5.2.3 Synthesis of Di-w-hexyl Malonates le 97 5.2.4 General Procedure for the Synthesis of Dialkyl Cyclopropane- 1,1- Dicarboxylate 2a, 2e and 2f 98 5.2.5 Polymerization Procedure 99 5.3 Results and Discussion 100 5.3.1 Monomer Syntheses 100 5.3.2 Polymerization of Cyclopropane- 1,1-Dicarboxylates 2a-g 101 5.3.3 Polymer Properties 1°6 ix 5.4 Conclusions HO 5.5 References 111 6. SYNTHESIS, CHARACTERIZATION AND THERMAL PROPERTIES OF POLY(CYCLOPROPANE- 1 , 1 -DICARBOXYLATE) POLYELECTROLUTES \ \ 2 6.1 Introduction j 12 6.2 Experimental Part 1 \ 3 6.2.1 Materials 113 6.2.2 Synthesis of Di-H-Propyl Malonate 113 6.2.3 Synthesis of Di-«-Propyl Cyclopropane- 1,1-Dicarboxylate (1) 114 6.2.4 Synthesis of Poly(Di-«-Propyl Cyclopropane- 1,1-Dicarboxylate) (Poly(l)) 114 6.2.5 Synthesis of the Dipotasium Salt of Poly(Cyclopropane-l,l-Dicarboxylic Acid) 2 115 6.2.6 Measurements 116 6.3 Results and Discussion 116 6.3.1 Polymer Synthesis 116 6.3.2 Structural Characterization of Polymer 2 119 6.4 Discussion 124 6.5 Conclusions and Perspectives 128 6.6 References 128 PART TWO: UV RADIATION CURING OF BIS(cc-SUBSTITUTED ACRYLATE)S 7. INTRODUCTION 132 7.1 Motivation..; 132 7.2 Structure/Reactivity of cc-Substituted Acrylates 135 7.2.1 Ceiling Temperature Effect 138 7.2.2 Steric Hindrance 139 7.2.3 Polar Effect 140 7.2.4 Other Effects 142 7.3 Radical Photo(co)polymerization of Multifunctional Monomers 143 7.3.1 Introduction 143 7.3.2 Polymerization Behavior of Multifunctional Monomers 144 x 7.3.2.1 Length and Flexibility of the Spacer between the Double Bonds ....146 7.3.2.2 Radiation Intensity, Photoinitiator Concentration, and Temperature 1 47 7.3.2.3 Copolymerization I4g 7.3.3 Experimental Approaches 149 7.3.4 Experimental Design in this Study 152 7.4 References 153 8.
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