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Synthetic and Mechanistic Studies of Poly(Vinyl Chloride) and Some Other Chlorinated Polymers W&M ScholarWorks Dissertations, Theses, and Masters Projects Theses, Dissertations, & Master Projects 2003 Synthetic and mechanistic studies of poly(vinyl chloride) and some other chlorinated polymers Xianlong Ge College of William & Mary - Arts & Sciences Follow this and additional works at: https://scholarworks.wm.edu/etd Part of the Organic Chemistry Commons, and the Polymer Chemistry Commons Recommended Citation Ge, Xianlong, "Synthetic and mechanistic studies of poly(vinyl chloride) and some other chlorinated polymers" (2003). Dissertations, Theses, and Masters Projects. Paper 1539623417. https://dx.doi.org/doi:10.21220/s2-drc1-7f95 This Dissertation is brought to you for free and open access by the Theses, Dissertations, & Master Projects at W&M ScholarWorks. It has been accepted for inclusion in Dissertations, Theses, and Masters Projects by an authorized administrator of W&M ScholarWorks. For more information, please contact [email protected]. SYNTHETIC AND MECHANISTIC STUDIES OF POLY(VINYL CHLORIDE) AND SOME OTHER CHLORINATED POLYMERS A Dissertation Presented to The Faculty of the Department of Applied Science The College of William and Mary in Virginia In Partial Fulfillment Of the Requirements for the Degree of Doctor of Philosophy by Xianlong Ge 2003 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. APPROVAL SHEET This dissertation is submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy Xianlong Ge Approved, May 2003 llliam H. Starnes, Jr. Robert A. Orwoll Robert L. Void Robert D. Pike Department of Chemistry Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ACKNOWLEDGMENTS..............................................................................................................viii LIST OF TABLES................................................................................................................... ix LIST OF FIGURES.................................................................................................................. x LIST OF SCHEMES..............................................................................................................xvi ABSTRACT............................................................................................................................xix CHAPTER 1. INTRODUCTION........................................................................................... 2 1.1 General .............................................................................................................................2 1.2 Poly(vinyl chloride) (PVC) ............................................................................................ 3 1.3 Synthesis of Polymers .....................................................................................................7 1.4 Degradation and Microstructure of Polymers ...............................................................8 CHAPTER 2. BACKGROUND........................................................................................... 10 2.1 General ........................................................................................................................... 10 2.2 Free-Radical Polymerization of 1,2-Dichloroethylene .............................................. 10 2.3 Selective Chlorination ...................................................................................................12 2.3.1 Poly(vinyl chloride) ...............................................................................................12 2.3.2 Chlorination of PV C ..............................................................................................12 2.3.3 Free-Radical Chlorination ..................................................................................... 14 2.3.4 Selective Chlorination with Chlorine in Complexing Solvents .........................15 2.3.5 PDCE from the Selective Chlorination of PVC? ................................................ 18 2.4 Chlorinated Polyacetylenes .......................................................................................... 19 2.4.1 Polyacetylene (PA ) ..............................................................................................19 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 2.4.2 Chlorinated Polyacetylene ....................................................................................23 2.4.3 Possible Chlorination Mechanisms ......................................................................25 2.4.4 Study on Chlorinated P A ......................................................................................26 2.5 Ring-Opening Metathesis Polymerization (ROMP) .................................................. 27 2.5.1 General Information .............................................................................................. 27 2.5.2 Mechanism of Olefin Metathesis and ROMP ..................................................... 27 2.5.3 Catalysts for ROMP .............................................................................................. 30 2.5.4 ROMP and Its Applications ..................................................................................34 2.6 Thermal Degradation of PVC Involving a Free-Radical Process .............................39 2.6.1 General ................................................................................................................... 39 2.6.2 Thermal Degradation of PVC: Initiation ............................................................ 40 2.6.3 PVC Degradation Mechanisms ............................................................................ 49 2.6.4 Thermal Stabilization of PVC ...............................................................................51 CHAPTER 3. EXPERIMENTAL......................................................................................... 52 3.1 Free-Radical Polymerization of 1,2-Dichloroethylene ..............................................52 3.1.1 Materials................................................................................................................ 52 3.1.2 NMR and GC/MS Measurements ........................................................................ 53 3.1.3 Attempts to Polymerize 1,2-Dichloroethylene .................................................... 53 3.1.4 Separation and Identification of cis and trans Dimers........................................54 3.2 Selective Chlorination .................................................................................................. 62 3.2.1 Materials................................................................................................................ 62 3.2.2 Synthesis of 2,4-Dichloropentane ........................................................................ 63 3.2.3 Synthesis of 4-Chloroheptane .............................................................................. 69 iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. 3.2.4 Synthesis of 4,4-Dichloroheptane ........................................................................ 74 3.2.5 Synthesis of 3,3-Dichloropentane............................................................................... 7g 3.2.6 Synthesis of 3,4-Dichloroheptane ........................................................................ 82 3.2.7 Synthesis of 2,3-Dichloropentane ........................................................................ 86 3.2.8 Chlorination of 2,4-Dichloropentane ...................................................................90 3.2.9 Chlorinations of 3-Chloropentane and 4-Chloroheptane ................................... 96 3.3 Chlorinated Polyacetylene ........................................................................................... 97 3.3.1 Materials................................................................................................................ 97 3.3.2 Synthesis and Chlorination of Shirakawa PA ..................................................... 99 3.3.3 Synthesis and Chlorination of Luttinger PA ......................................................101 3.3.4 Thermal Analysis of Chlorinated Polyacetylene .............................................. 104 3.3.5 Reductive Dechlorination of Chlorinated Luttinger PA ...................................107 3.4 Ring-Opening Metathesis Polymerization ................................................................109 3.4.1 Materials.............................................................................................................. 109 3.4.2 Synthesis of Monomers and Model Compounds .............................................. 112 3.4.3 Thermal Degradation of Mono-, Di-, Tri-, and Tetrachlorides ........................143 3.4.4 Chlorination of cA-l,4-Dichloro-2-butene ........................................................144 3.4.5 Synthesis of New Chlorinated Polymers ...........................................................147 3.4.6 Thermal Analysis of New Chlorinated Polymers ............................................. 163 3.5 Thermal Degradation of PVC ....................................................................................164 3.5.1 Materials...............................................................................................................164 3.5.2 Dehydrochlorination Kinetics .............................................................................165
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