POLYMER CHEMISTRY AN INTRODUCTION. Malcolm P. Stevens. University of Hartford. New York Oxford OXFORD UNIVERSITY PRESS

T H I R D E D I T I O N POLYMER CHEMISTRY AN INTRODUCTION Malcolm P. Stevens University of Hartford New York Oxford OXFORD UNIVERSITY PRESS 1999

CONTENTS Preface, PART I xvii POLYMER STRUCTURE AND PROPERTIES I. Basic principles, 3 1.1 Introduction and historical development, 3 1.2 Definitions, 6 1.3 Polymerization processes, 10 1.4 Step-reaction polymerization, 12 1.5 Chain-reaction polymerization, 13 1.6 Step-reaction addition and chain-reaction condensation, 15 1.7 Nomenclature, 16 1.7.1 Vinyl polymers, 17 1.7.2 Vinyl copolymers, 20 1.7.3 Nonvinyl polymers, 21 1.7.4 Nonvinyl copolymers, 24 1.7.5 End groups, 24 1.7.6 Abbreviations, 25 1.8 Industrial polymers, 25 1.8.1 Plastics, 25 1.8.2 fifaers, 27 1.8.3 Rubber (elastomers), 28 1.8.4 Coatings and adhesives, 29 1.9 Polymer recycling, 30 References, 31 Review exercises, 32 vii

Vlll Contents 2. Molecular weight and polymer Solutions, 35 2.1 Number average and weight average molecular weight, 35 2.2 Polymer Solutions, 37 2.3 Measurement of number average molecular weight, 42 2.3.1 End-group analysis, 42 2.3.2 Membrane osmometry, 43 2.3.3 Cryoscopy and ebulliometry, 46 2.3.4 Vapor pressure osmometry, 46 2.3.5 Mass spectrometry, 46 2.3.6 Refractive index measurements, 48 2.4 Measurement of weight average molecular weight, 48 2.4.1 Light scattering, 48 2.4.2 Ulcentrifugation, 50 2.5 Viscometry, 50 2.6 Molecular weight distribution, 53 2.6.1 Gel permeation chromatography (GPC), 53 2.6.2 Fractional Solution, 57 2.6.3 Fractional preäpitation, 58 2.6.4 Thin-layer chromatography (TLC), 58 References, 58 Review exercises, 59 3. Chemical structure and polymer morphology, 61 3.1 Introduction, 61 3.2 Molecular weight and intermolecular forces, 62 3.3 The amorphous State rheology, 63 3.4 Glass transition temperature, 70 3.5 Stereochemistry, 74 3.6 Crystallinity, 79 3.7 Liquid crystallinity, 83 3.8 Chemical crosslinking, 85 3.9 Physical crosslinking, 86 3.10 Polymer blends, 87 References, 91 Review exercises, 93

Contents ix 4. Chemical structure and polymer properties, 96 4.1 Introduction, 96 4.2 Fabrication methods, 96 4.3 Mechanical properties, 100 4.4 Thermal stability, 106 4.5 Flammability and flame resistance, I 10 4.6 Chemical resistance, I 12 4.7 Degradability, I 14 4.8 Electrical conductivity, I 17 4.9 Nonlinear optical properties, 120 4.10 Additives, 121 References, 124 Review exercises, 127 5. Evaluation, characterization, and analysis of polymers, 129 5.1 Introduction, 129 5.2 Chemical methods of analysis, 130 5.3 Spectroscopic methods of analysis, 130 5.3.1 Infrared, 131 5.3.2 Raman, 133 5.3.3 Nuclear magnetic resonance, 134 5.3.4 Electron spin resonance, 138 5.3.5 Ultraviolet (UV)-visible, 139 5.3.6 Fluorescence, 139 5.4 X-ray, electron, and neutron scattering, 140 5.5 Characterization and analysis of polymer surfaces, 141 5.5.1 Scanning electron microscopy (SEM), 143 5.5.2 Attenuated total reflectance spectroscopy (ATR), 143 5.5.3 Photoacoustic spectroscopy (PAS), 144 5.5.4 Electron spectroscopy for chemical analysis (or applications) (ESCA) and Auger electron spectroscopy (AES), 145 5.5.5 Secondary-ion mass spectrometry (SIMS) and ion-scattering spectroscopy (ISS), 147 5.5.6 Atomic force microscopy (AFM), 148 5.6 Thermal analysis, 149 5.6.1 Differential scanning calorimetry (DSC) and differential thermal analysis (DTA), 149

X Contents 5.6.2 Thermomechanical analysis (TMA), 152 5.6.3 Thermogravimetric analysis (TGA), 152 5.6.4 Pyrolysis-gas chromatography (PGC), 153 5.6.5 Flammability testing, 154 5.7 Measurement of mechanical properties, 156 5.8 Evaluation of chemical resistance, 159 5.9 Evaluation of electrical properties, 159 References, 160 Review exercises, 163 PART II VINYL POLYMERS 6. Free radical polymerization, 167 6.1 Introduction, 167 6.2 Free radical initiators, 169 6.2.1 Peroxides and hydroperoxides, 169 6.2.2 Azo Compounds, 171 6.2.3 Redox initiators, 171 6.2.4 Photoinitiators, 172 6.2.5 Thermal polymerization, 172 6.2.6 Electrochemical polymerization, 173 6.3 Techniques of free radical polymerization, 173 6.3.1 Bulk, 174 6.3.2 Suspension, 174 6.3.3 Solution, 174 6.3.4 Emulsion, 175 6.4 Kinetics and mechanism of polymerization, 176 6.5 Stereochemistry of polymerization, 186 6.6 Polymerization of dienes, 188 6.6. / Isolated dienes, 188 6.6.2 Conjugated dienes, 189 6.7 Monomer reactivity, 191 6.8 Copolymerization, 194 References, 201 Review exercises, 202

Contents xi 7. lonic polymerization, 205 7.1 Introduction, 205 7.2 Cationic polymerization, 205 7.2.1 Cationic initiators, 205 7.2.2 Mechanism, kinetics, and reactivity in cationic polymerization, 207 7.2.3 Stereochemistry of cationic polymerization, 21 3 7.2.4 Cationic copolymerization, 215 7.2.5 Isomerization in cationic polymerization, 217 7.3 Anionic polymerization, 217 7.3.1 Anionic initiators, 217 7.3.2 Mechanism, kinetics, and reactivity in anionic polymerization, 219 7.3.3 Stereochemistry of anionic polymerization, 223 7.3.4 Anionic copolymerization, 225 7.4 Group transfer polymerization, 227 References, 230 Review exercises, 231 8. Vinyl polymerization with complex coordination catalysts, 234 8.1 Introduction, 234 8.2 Heterogeneous Ziegler-Natta polymerization, 236 8.2.1 Heterogeneous catalysts, 236 8.2.2 Mechanism and reactivity in heterogeneous polymerization, 238 8.2.3 Stereochemistry of heterogeneous polymerization, 242 8.2.4 Polymerization ofdienes, 243 8.3 Homogeneous Ziegler-Natta polymerization, 245 8.3.1 Metallocene catalysts, 245 8.3.2 Mechanism and reactivity with metallocene catalysts, 246 8.3.3 Stereochemistry of metallocene-catalyzed polymerization, 248 8.4 Ziegler-Natta copolymerization, 249 8.5 Supported metal oxide catalysts, 251 8.6 Alfin catalysts, 252 8.7 Metathesis polymerization, 252

xii Contents 8.7.1 Ring-opening metathesis polymerization, 253 8.7.2 Acyclic diene metathesis polymerization, 255 References, 255 Review exercises, 257 9. Reactions of vinyl polymers, 259 9.1 Introduction, 259 9.2 Functional group reactions, 260 9.2.1 Introduction of new functional groups, 260 9.2.2 Conversion of functional groups, 261 9.3 Ring-forming reactions, 263 9.4 Crosslinking, 265 9.4.1 Vulcanization, 265 9.4.2 Radiation crosslinking, 267 9.4.3 Photochemical crosslinking, 267 9.4.4 Crosslinking through labile functional groups, 271 9.4.5 lonic crosslinking, 272 9.5 Block and graft copolymer formation, 272 9.5.1 Block copolymers, 272 9.5.2 Graft copolymers, 273 9.6 Polymer degradation, 276 9.6.1 Chemical degradation, 276 9.6.2 Thermal degradation, 277 9.6.3 Degradation by radiation, 278 References, 279 Review exercises, 281 PART III NONVINYL POLYMERS 10. Step-reaction and ring-opening polymerization, 285 10.1 Introduction, 285 10.2 Step-reaction polymerization kinetics, 285 10.3 Stoichiometric imbalance, 290 10.4 Molecular weight distribution, 292 10.5 Network step polymerization, 295 10.6 Step-reaction copolymerization, 297 10.7 Step polymerization techniques, 298

Contents 10.8 Dendritic polymers, 301 10.9 Ring-opening polymerization, 304 References, 306 Review exercises, 307 11. Polyethers, polysulfides, and related polymers, 309 ll.l Introduction, 309 I 1.2 Preparation of polyethers by chain-reaction and ring-opening polymerization, 309 11.2.1 Polymerization of carbonyl Compounds, 309 /1.2.2 Stereochemistry ofaldehyde polymerization, 313 /1.2.3 Polymerization ofcyclic ethers, 3 14 /1.2.4 Stereochemistry of epoxide polymerization, 320 11.3 Preparation of polyethers by step-reaction polymerization, 321 /1.3.1 Synthesis of polyethers from glycols and bisphenols, 321 11.3.2 Polyacetals and polyketals, 322 11.3.3 Poly(phenylene oxide)s, 324 /1.3.4 Epoxy resins, 326 11.4 Polysulfides, poly(alkylene polysulfide)s, and polysulfones, 329 11.4.1 Polysulfides, 329 11.4.2 Poly(alkylene polysulfide)s, 331 /1.4.3 Polysulfones, 332 References, 333 Review exercises, 334 12. Polyesters, 338 12.1 Introduction, 338 12.2 Linear polyesters, 341 12.2.1 Preparation of polyesters by polycondensation reactions, 341 12.2.2 Polycarbonates, 346 / 2.2.3 Preparation of polyesters by ring-opening polymerizavon, 348 12.2.4 Microbial polyesters, 352 12.3 Hyperbranched polyesters, 353 12.4 Crosslinked polyesters, 354 12.4.1 Saturated polyester resins, 354 12.4.2 Unsaturated polyesters, 356 References, 359 Review exercises, 360

XIV Contents 13. Polyamides and related polymers, 364 13.1 Introduction, 364 13.2 Polyamides, 366 13.2.1 Preparation ofpolyamides by polycondensation reactions, 366 13.2.2 Polymerization oflactams, 369 13.2.3 Miscellaneous methods of preparing polyamides, 372 13.3 Properties of polyamides, 374 13.4 Polyureas, 377 13.5 Polyurethanes, 378 13.6 Polyhydrazides, 382 13.7 Polyimides, 382 References, 388 Review exercises, 390 14. Phenol-, urea-, and melamine-formaldehyde polymers, 395 14.1 Introduction, 395 14.2 Phenol-formaldehyde polymers: resoles, 396 14.3 Phenol-formaldehyde polymers: novolacs, 399 14.4 Chemical modifications of phenolic resins, 402 14.5 Urea-formaldehyde polymers, 404 14.6 Melamine-formaldehyde polymers, 406 References, 407 Review exercises, 408 15. Heterocyclic polymers, 409 15.1 Introduction, 409 15.2 Polypyrrole, polyfuran, and polythiophene, 412 15.3 Polycyanurate and polyphthalocyanine resins, 413 15.4 Heterocyclic polymers formed from precursor polymers, 414 15.5 Heterocyclic polymers formed from polyfunctional monomers, 415 15.5.1 Polybenzimidazoles, 415 15.5.2 Polybenzoxazoles and polybenzothiazoles, 417 15.5.3 Polyhydantoins, 418 15.5.4 Poly(parabanic aäd)s, 418 15.5.5 Polyquinoxalines and polypyrazines, 419 15.5.6 Polypyrazoles and polyimidazoles, 419 15.5.7 Poly(as-triazine)s and polytriazolines, 420

Contents 15.5.8 Polyquinolines and polyanthrazolines, 421 References, 421 Review exercises, 422 16. Inorganic and partially inorganic polymers, 425 16.1 Introduction, 425 16.2 Poly(sulfur nitride), 426 16.3 Polysiloxanes, 427 16.4 Polysilanes, 430 16.5 Polyphosphazenes, 431 16.6 Carborane polymers, 434 16.7 Organometallic polymers, 436 16.8 Coordination polymers, 438 References, 442 Review exercises, 444 17. Miscellaneous organic polymers, 447 17.1 Introduction, 447 17.2 Miscellaneous unsaturated polymers, 447 / 7.2.1 Polycarbodiimides, 447 / 7.2.2 Polyimines, 449 / 7.2.3 Polymers containing carbon-carbon double bonds, 450 / 7.2.4 Azo polymers, 450 / 7.2.5 Polymers containing carbon-carbon triple bonds, 451 17.3 Poly(p-phenylene) and poly(p-xylylene), 452 / 7.3.1 Poly(p-phenylene), 452 / 7.3.2 Poly(p-xylylene), 454 17.4 Friedel-Crafts polymers, 455 17.5 Cycloaddition polymerization, 456 / 7.5.1 Diels-Alder polymerization, 456 / 7.5.2 2 + 2 Cycloaddition polymerization, 459 17.6 Polyanhydrides, 460 17.7 Polyamines, 461 17.8 Charge-transfer polymers, 464 17.9 lonic polymers, 467 References, 469 Review exercises, 471

xvi Contents 18. Natural polymers, 476 18.1 Introduction, 476 18.2 Miscellaneous natural polymers, 476 18.2.1 Rubber, 476 18.2.2 Lignin, humus, coal, and kerogen, 479 18.2.3 Asphaltenes, 481 18.2.4 Shellac, 481 18.2.5 Amber, 482 18.2.6 Tall oil-derived polymers, 482 18.3 Polysaccharides, 484 18.3.1 Cellulose, 484 18.3.2 Regenerated cellulose, 485 18.3.3 Derivatives of cellulose, 486 18.3.4 Starch, 489 18.3.5 Derivatives of starch, 490 18.3.6 Other Polysaccharides, 491 184 Proteins, 492 / 8.4.1 Amino acids, Polypeptides, and proteins, 492 18.4.2 Protein structure, 495 18.4.3 Synthesis of Polypeptides and proteins, 498 18.4.4 Wool, silk, Collagen, and regenerated protein, 500 18.5 Nucleic acids, 502 18.5.1 Nucleic acid structure, 502 18.5.2 Nucleic acid synthesis, 507 18.6 Conclusion, 510 References, 510 Review exercises, 513 Appendix A Commonly used polymer abbreviations, 515 Appendix B Polymer literature, 517 Appendix C Index, 535 Sources of laboratory experiments in polymer chemistry, 526