AN INTRODUCTION TO POLYMER PHYSICS
CONTENTS 1 INTRODUCTION 1 1 POLYMERS AND THE SCOPE OF THE BOOK 1 2 A BRIEF HISTORY OF THE DEVELOPMENT OF SYNTHETIC POLYMERS 1 3 THE CHEMICAL NATURE OF POLYMERS 1 3 1 INTRODUCTION 1 3 2 THE CLASSI?CATION OF POLYMERS 1 3 3 ‘CLASSICAL’ POLYMERISATION PROCESSES 1 3 4 NEWER POLYMERS AND POLYMERISATION PROCESSES 1 4 PROPERTIES AND APPLICATIONS 1 5 POLYMER PROCESSING 1 5 1 INTRODUCTION 1 5 2 ADDITIVES AND COMPOSITES 1 5 3 PROCESSING METHODS 1 6 FURTHER READING 1 6 1 SOME GENERAL POLYMER TEXTS 1 6 2 FURTHER READING SPECI?CALLY FOR CHAPTER 2 SOME PHYSICAL TECHNIQUES FOR STUDYING POLYMERS 2 1 INTRODUCTION 2 2 DI?ERENTIAL SCANNING CALORIMETRY (DSC) AND DI?ERENTIAL THERMAL ANALYSIS (DTA) 2 3 DENSITY MEASUREMENT 2 4 LIGHT SCATTERING 2 5 X-RAY SCATTERING 2 5 1 WIDE-ANGLE SCATTERING (WAXS) 2 5 2 SMALL-ANGLE SCATTERING (SAXS) 2 6 INFRARED AND RAMAN SPECTROSCOPY 2 6 1 THE PRINCIPLES OF INFRARED AND RAMAN SPECTROSCOPY 2 6 2 SPECTROMETERS FOR INFRARED AND RAMAN SPECTROSCOPY 2 6 3 THE INFRARED AND RAMAN SPECTRA OF POLYMERS 2 6 4 QUANTITATIVE INFRARED SPECTROSCOPY – THE LAMBERT–BEER LAW 2 7 NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY (NMR) 2 7 1 INTRODUCTION 2 7 2 NMR SPECTROMETERS AND EXPERIMENTS 2 7 3 CHEMICAL SHIFTS AND SPIN–SPIN INTERACTIONS 2 7 4 MAGIC-ANGLE SPINNING, DIPOLAR DECOUPLING AND CROSS POLARISATION 2 7 5 SPIN DI?USION 2 7 6 MULTI-DIMENSIONAL NMR 2 7 7 QUADRUPOLAR COUPLING AND 2H SPECTRA 2 8 OPTICAL AND ELECTRON MICROSCOPY 2 8 1 OPTICAL MICROSCOPY 2 8 2 ELECTRON MICROSCOPY 2 9 FURTHER READING 3 MOLECULAR SIZES AND SHAPES AND ORDERED STRUCTURES 3 1 INTRODUCTION 3 2 DISTRIBUTIONS OF MOLAR MASS AND THEIR DETERMINATION 3 2 1 NUMBER-AVERAGE AND WEIGHT-AVERAGE MOLAR MASSES 3 2 2 DETERMINATION OF MOLAR MASSES AND DISTRIBUTIONS 3 3 THE SHAPES OF POLYMER MOLECULES 3 3 1 BONDING AND THE SHAPES OF MOLECULES 3 3 2 CONFORMATIONS AND CHAIN STATISTICS 3 3 3 THE SINGLE FREELY JOINTED CHAIN 3 3 4 MORE REALISTIC CHAINS – THE EXCLUDED-VOLUME E?ECT 3 3 5 CHAIN ?EXIBILITY AND THE PERSISTENCE LENGTH 3 4 EVIDENCE FOR ORDERED STRUCTURES IN SOLID POLYMERS 3 4 1 WIDE-ANGLE X-RAY SCATTERING – WAXS 3 4 2 SMALL-ANGLE X-RAY SCATTERING – SAXS 3 4 3 LIGHT SCATTERING 3 4 4 OPTICAL MICROSCOPY 3 5 FURTHER READING 3 6 PROBLEMS 4 REGULAR CHAINS AND CRYSTALLINITY 4 1 REGULAR AND IRREGULAR CHAINS 4 1 1 INTRODUCTION 4 1 2 POLYMERS WITH ‘AUTOMATIC’ REGULARITY 4 1 3 VINYL POLYMERS AND TACTICITY 4 1 4 POLYDIENES 4 1 5 HELICAL MOLECULES 4 2 THE DETERMINATION OF CRYSTAL STRUCTURES BY X-RAY DI?RACTION 4 2 1 INTRODUCTION 4 2 2 FIBRE PATTERNS AND THE UNIT CELL 4 2 3 ACTUAL CHAIN CONFORMATIONS AND CRYSTAL STRUCTURES 4 3 INFORMATION ABOUT CRYSTAL STRUCTURES FROM OTHER METHODS 4 4 CRYSTAL STRUCTURES OF SOME COMMON POLYMERS 4 4 1 POLYETHYLENE 4 4 2 SYNDIOTACTIC POLY(VINYL CHLORIDE) (PVC) 4 4 3 POLY(ETHYLENE TEREPHTHALATE) (PET) 4 4 4 THE NYLONS (POLYAMIDES) 4 5 FURTHER READING 4 6 PROBLEMS 5 MORPHOLOGY AND MOTION 5 1 INTRODUCTION 5 2 THE DEGREE OF CRYSTALLINITY 5 2 1 INTRODUCTION 5 2 2 EXPERIMENTAL DETERMINATION OF CRYSTALLINITY 5 3 CRYSTALLITES 5 3 1 THE FRINGED-MICELLE MODEL 5 3 2 CHAIN-FOLDED CRYSTALLITES 5 3 3 EXTENDED-CHAIN CRYSTALLITES 5 4 NON-CRYSTALLINE REGIONS AND POLYMER MACRO-CONFORMATIONS 5 4 1 NON-CRYSTALLINE REGIONS 5 4 2 POLYMER MACRO-CONFORMATIONS 5 4 3 LAMELLAR STACKS 5 5 SPHERULITES AND OTHER POLYCRYSTALLINE STRUCTURES 5 5 1 OPTICAL MICROSCOPY OF SPHERULITES 5 5 2 LIGHT SCATTERING BY SPHERULITES 5 5 3 OTHER METHODS FOR OBSERVING SPHERULITES 5 5 4 AXIALITES AND SHISH-KEBABS 5 6 CRYSTALLISATION AND MELTING 5 6 1 THE MELTING TEMPERATURE 5 6 2 THE RATE OF CRYSTALLISATION 5 6 3 THEORIES OF CHAIN FOLDING AND LAMELLAR THICKNESS 5 7 MOLECULAR MOTION 5 7 1 INTRODUCTION 5 7 2 NMR, MECHANICAL AND ELECTRICAL RELAXATION 5 7 3 THE SITE-MODEL THEORY 5 7 4 THREE NMR STUDIES OF RELAXATIONS WITH WIDELY DI?ERENT VALUES OF C 5 7 5 FURTHER NMR EVIDENCE FOR VARIOUS MOTIONS IN POLYMERS 5 8 FURTHER READING 5 9 PROBLEMS 6 MECHANICAL PROPERTIES I – TIME-INDEPENDENT ELASTICITY 6 1 INTRODUCTION TO THE MECHANICAL PROPERTIES OF POLYMERS 6 2 ELASTIC PROPERTIES OF ISOTROPIC POLYMERS AT SMALL STRAINS 6 2 1 THE ELASTIC CONSTANTS OF ISOTROPIC MEDIA AT SMALL STRAINS 6 2 2 THE SMALL-STRAIN PROPERTIES OF ISOTROPIC POLYMERS 6 3 THE PHENOMENOLOGY OF RUBBER ELASTICITY 6 3 1 INTRODUCTION 6 3 2 THE TRANSITION TO LARGE-STRAIN ELASTICITY 6 3 3 STRAIN–ENERGY FUNCTIONS 6 3 4 THE NEO-HOOKEIAN SOLID 6 4 THE STATISTICAL THEORY OF RUBBER ELASTICITY 6 4 1 INTRODUCTION 6 4 2 THE FUNDAMENTAL MECHANISM OF RUBBER ELASTICITY 6 4 3 THE THERMODYNAMICS OF RUBBER ELASTICITY 6 4 4 DEVELOPMENT OF THE STATISTICAL THEORY 6 5 MODI?CATIONS OF THE SIMPLE MOLECULAR AND PHENOMENOLOGICAL THEORIES 6 6 FURTHER READING 6 7 PROBLEMS 7 MECHANICAL PROPERTIES II – LINEAR VISCOELASTICITY 7 1 INTRODUCTION AND DE?NITIONS 7 1 1 INTRODUCTION 7 1 2 CREEP 7 1 3 STRESS-RELAXATION 7 1 4 THE BOLTZMANN SUPERPOSITION PRINCIPLE (BSP) 7 2 MECHANICAL MODELS 7 2 1 INTRODUCTION 7 2 2 THE MAXWELL MODEL 7 2 3 THE KELVIN OR VOIGT MODEL 7 2 4 THE STANDARD LINEAR SOLID 7 2 5 REAL MATERIALS – RELAXATION-TIME AND RETARDATION-TIME SPECTRA 7 3 EXPERIMENTAL METHODS FOR STUDYING VISCOELASTIC BEHAVIOUR 7 3 1 TRANSIENT MEASUREMENTS 7 3 2 DYNAMIC MEASUREMENTS – THE COMPLEX MODULUS AND COMPLIANCE 7 3 3 DYNAMIC MEASUREMENTS; EXAMPLES 7 4 TIME–TEMPERATURE EQUIVALENCE AND SUPERPOSITION 7 5 THE GLASS TRANSITION IN AMORPHOUS POLYMERS 7 5 1 THE DETERMINATION OF THE GLASS-TRANSITION TEMPERATURE 7 5 2 THE TEMPERATURE DEPENDENCE OF THE SHIFT FACTOR: THE VFT AND WLF EQUATIONS 7 5 3 THEORIES OF THE GLASS TRANSITION 7 5 4 FACTORS THAT A?ECT THE VALUE OF TG 7 6 RELAXATIONS FOR AMORPHOUS AND CRYSTALLINE POLYMERS 7 6 1 INTRODUCTION 7 6 2 AMORPHOUS POLYMERS 7 6 3 CRYSTALLINE POLYMERS 7 6 4 FINAL REMARKS 7 7 FURTHER READING 7 8 PROBLEMS 8 YIELD AND FRACTURE OF POLYMERS 8 1 INTRODUCTION 8 2 YIELD 8 2 1 INTRODUCTION 8 2 2 THE MECHANISM OF YIELDING – COLD DRAWING AND THE CONSIDE` RE CONSTRUCTION 8 2 3 YIELD CRITERIA 8 2 4 THE PRESSURE DEPENDENCE OF YIELD 8 2 5 TEMPERATURE AND STRAIN-RATE DEPENDENCES OF YIELD 8 3 FRACTURE 8 3 1 INTRODUCTION 8 3 2 THEORIES OF FRACTURE; TOUGHNESS PARAMETERS 8 3 3 EXPERIMENTAL DETERMINATION OF FRACTURE TOUGHNESS 8 3 4 CRAZING 8 3 5 IMPACT TESTING OF POLYMERS 8 4 FURTHER READING 8 5 PROBLEMS 9 ELECTRICAL AND OPTICAL PROPERTIES 9 1 INTRODUCTION 9 2 ELECTRICAL POLARISATION 9 2 1 THE DIELECTRIC CONSTANT AND THE REFRACTIVE INDEX 9 2 2 MOLECULAR POLARISABILITY AND THE LOW-FREQUENCY DIELECTRIC CONSTANT 9 2 3 BOND POLARISABILITIES AND GROUP DIPOLE MOMENTS 9 2 4 DIELECTRIC RELAXATION 9 2 5 THE DIELECTRIC CONSTANTS AND RELAXATIONS OF POLYMERS 9 3 CONDUCTING POLYMERS 9 3 1 INTRODUCTION 9 3 2 IONIC CONDUCTION 9 3 3 ELECTRICAL CONDUCTION IN METALS AND SEMICONDUCTORS 9 3 4 ELECTRONIC CONDUCTION IN POLYMERS 9 4 OPTICAL PROPERTIES OF POLYMERS 9 4 1 INTRODUCTION 9 4 2 TRANSPARENCY AND COLOURLESSNESS 9 4 3 THE REFRACTIVE INDEX 9 5 FURTHER READING 9 6 PROBLEMS 10 ORIENTED POLYMERS I – PRODUCTION AND CHARACTERISATION 10 1 INTRODUCTION – THE MEANING AND IMPORTANCE OF ORIENTATION 10 2 THE PRODUCTION OF ORIENTATION IN SYNTHETIC POLYMERS 10 2 1 UNDESIRABLE OR INCIDENTAL ORIENTATION 10 2 2 DELIBERATE ORIENTATION BY PROCESSING IN THE SOLID STATE 10 2 3 DELIBERATE ORIENTATION BY PROCESSING IN THE ?UID STATE 10 2 4 COLD DRAWING AND THE NATURAL DRAW RATIO 10 3 THE MATHEMATICAL DESCRIPTION OF MOLECULAR ORIENTATION 10 4 EXPERIMENTAL METHODS FOR INVESTIGATING THE DEGREE OF ORIENTATION 10 4 1 MEASUREMENT OF OPTICAL REFRACTIVE INDICES OR BIREFRINGENCE 10 4 2 MEASUREMENT OF INFRARED DICHROISM 10 4 3 POLARISED ?UORESCENCE 10 4 4 RAMAN SPECTROSCOPY 10 4 5 WIDE-ANGLE X-RAY SCATTERING 10 5 THE COMBINATION OF METHODS FOR TWO-PHASE SYSTEMS 10 6 METHODS OF REPRESENTING TYPES OF ORIENTATION 10 6 1 TRIANGLE DIAGRAMS 10 6 2 POLE ?GURES 10 6 3 LIMITATIONS OF THE REPRESENTATIONS 10 7 FURTHER READING 10 8 PROBLEMS 11 ORIENTED POLYMERS II – MODELS AND PROPERTIES 11 1 INTRODUCTION 11 2 MODELS FOR MOLECULAR ORIENTATION 11 2 1 THE A?NE RUBBER DEFORMATION SCHEME 11 2 2 THE AGGREGATE OR PSEUDO-A?NE DEFORMATION SCHEME 11 3 COMPARISON BETWEEN THEORY AND EXPERIMENT 11 3 1 INTRODUCTION 11 3 2 THE A?NE RUBBER MODEL AND ‘FROZEN-IN’ ORIENTATION 11 3 3 THE A?NE RUBBER MODEL AND THE STRESS-OPTICAL COE?CIENT 11 3 4 THE PSEUDO-A?NE AGGREGATE MODEL 11 4 COMPARISON BETWEEN PREDICTED AND OBSERVED ELASTIC PROPERTIES 11 4 1 INTRODUCTION 11 4 2 THE ELASTIC CONSTANTS AND THE WARD AGGREGATE MODEL 11 5 TAKAYANAGI COMPOSITE MODELS 11 6 HIGHLY ORIENTED POLYMERS AND ULTIMATE MODULI 11 6 1 ULTIMATE MODULI 11 6 2 MODELS FOR HIGHLY ORIENTED POLYETHYLENE 11 7 FURTHER READING 11 8 PROBLEMS 12 POLYMER BLENDS, COPOLYMERS AND LIQUID-CRYSTAL POLYMERS 12 1 INTRODUCTION 12 2 POLYMER BLENDS 12 2 1 INTRODUCTION 12 2 2 CONDITIONS FOR POLYMER–POLYMER MISCIBILITY 12 2 3 EXPERIMENTAL DETECTION OF MISCIBILITY 12 2 4 COMPATIBILISATION AND EXAMPLES OF POLYMER BLENDS 12 2 5 MORPHOLOGY 12 2 6 PROPERTIES AND APPLICATIONS 12 3 COPOLYMERS 12 3 1 INTRODUCTION AND NOMENCLATURE 12 3 2 LINEAR COPOLYMERS: SEGREGATION AND MELT MORPHOLOGY 12 3 3 COPOLYMERS COMBINING ELASTOMERIC AND RIGID COMPONENTS 12 3 4 SEMICRYSTALLINE BLOCK COPOLYMERS 12 4 LIQUID-CRYSTAL POLYMERS 12 4 1 INTRODUCTION 12 4 2 TYPES OF MESOPHASES FOR SMALL MOLECULES 12 4 3 TYPES OF LIQUID-CRYSTAL POLYMERS 12 4 4 THE THEORY OF LIQUID-CRYSTAL ALIGNMENT 12 4 5 THE PROCESSING OF LIQUID-CRYSTAL POLYMERS 12 4 6 THE PHYSICAL STRUCTURE OF SOLIDS FROM LIQUID-CRYSTAL POLYMERS 12 4 7 THE PROPERTIES AND APPLICATIONS OF LIQUID-CRYSTAL POLYMERS 12 5 FURTHER READING 12 6 PROBLEMS