Polymer Crystallization

Transcription

1 G. Reiter J.-U. Sommer (Eds.) Polymer Crystallization Observations, Concepts and Interpretations Springer

2 Table of Contents 1 Introduction Jens-Uwe Sommer and Günter Reiter 1 2 Polymer Crystallization Viewed in the General Context of Particle Formation and Crystallization Jens Rieger Introduction Classical Nucleation Theory Precursors Spinodal vs. Binodal Phase Separation Computer Simulations of the Early Stages of Particle Formation and Crystallization Control of Crystallization by Additives Ostwald's Rule of Stages Ostwald Ripening vs. Secondary Crystallization Discussion 14 References 14 3 Role of Metastable Phases in Polymer Crystallization; Early Stages of Crystal Growth Sanjay Rastogi Introduction Experimental Section Materials High Pressure Cell Polarising Optical Microscopy Wide Angle X-ray Scattering Results and Discussion Polyethylene - A Summary of Previously Reported Results on Crystallisation of Single Crystals in Polyethylene Melts Experimental Observations on a Crystal after Its Transformation from the Metastable Hexagonal Phase into the Thermodynamically Stable Orthorhombic Phase Multilayering: Primary and Secondary Thickening 25

3 VIII Table of Contents Size Influence in Phase Transformation: Stahle, Metastable and Transient States of a Phase Implications to Crystallisation at Atmospheric Pressure An Application of Enhanced Chain Mobility in the Transient Phase of Ultra High Molecular Weight Polyethylene Conclusions 44 References 46 4 A Comparative Study of the Mechanisms of Initial Crystallization and Recrystallization after Melting in Syndiotactic Polypropene and Isotactic Polystyrene Mahmoud AI-Hussein, Gert Strobl Introduction Experimental Sample Characteristics and Preparation SAXS Measurements Results Discussion 60 References 62 5 Polymer Crystallization Viewed by Magnetic Alignment Tsunehisa Kimura Introduction Principle of Diamagnetic Alignment Mesophase Detected by Magnetic Alignment Molten States Magneto-Clapeyron : Concluding Remarks 79 References 80 6 Following Crystallization in Polymers Using AFM Jamie K. Hobbs Background The Use of AFM to Follow Crystallization Sample Preparation Results and Discussion The Crystal Melt Interface On the Surface Texture of Polyethylene Lamellae The Melting of Isolated Lamellae Conclusions 95 References 96

4 Table of Contents IX 7 Atomic Force Microscopy Studies of Semicrystalline Polymers at Variable Temperature Dimitri A. Ivanov, Sergei N. Magonov Introduction Studies of Polymers in Tapping Mode Tip-Sample Forces Image Resolution Sample Preparation Practical Examples of Imaging of Semi-crystalline Polymers at Variable Temperature Flexible Chain Polymers Semi-rigid Chain Polymers Conclusions 127 References Crystallization of Polymers in Thin Films: Model Experiments Günter Reiter, Gilles Castelein, Jens-Uwe Sommer Introduction Experimental Section Polymers Sample Preparation Observation Techniques Results and Discussion Crystallization of Adsorbed PEO Homopolymer Monolayers Relaxations of Polymer Crystals AFTER Formation Discrete Variation of Lamellar Spacings with Temperature in Block Copolymer Systems Individual Crystallization and Melting of Polymer Nanocrystals Conclusions References A Generic Model for Growth and Morphogenesis of Polymer Crystals in Two Dimensions Jens-Uwe Sommer, Günter Reiter Introduction A Lattice Model for Crystallization in Polymer Monolayers Growth Morphologies Self-organized Crystal Thickness and Growth Velocity Reorganization of the Polymer Crystal Annealing and Morphogenesis - The "Crystalline Liquid State" Heating with a Constant Rate and the Role of Morphogenesis Conclusions 175 References 176

5 X Table of Contents 10 Structure Formation and Chain-Folding in Supercooled Polymer Melts. Some Ideas from MD Simulations with a Coarse-Grained Model Hendrik Meyer Introduction The Model CG-PVA: Excluded Volume, Connectivity and Rotational Isomeric States Simulation Details Structure Formation in a Melt of Short Chams Homogeneous Nucleation Positional, Orientational and Conformational Order Chain-Length Dependence of Crystallization and Melting Temperatures Chain-Folding in Isothermal Relaxation of Long Chains Slightly Entangled Chains (N = 100) Entangled Chains (TV = 400) Discussion and Conclusions 192 References Lamellar Ethylene Oxide Butadiene Block Copolymer Films as Model Systems for Conflned Crystallisation Wim H. de Jeu Introduction Experimental Situation Discussion and Modelling Conclusions and Open Questions 205 References Crystallization Kinetical Peculiarities in Polymer Blends Bernd-J. Jungnickel Introduction Immiscible Blends: Fractionated Crystallization Blends with Miscibility Gap: Interface Crossing Crystallization Miscible Crystallizing Blends: Pseudoeutectic Behaviour Miscible Blends: Crystallization Induced Composition Inhomogeneities Miscible Blends: Competition Between Crystallization and Vitrification Blends with Miscibility Gap: Competition Between Crystallization and Mixing/Demixing Picture Gallery Concluding Remarks 236 References 236

6 Table of Contents XI 13 Dendritic Growth of Polyethylene Oxide on Patterned Surfaces Hans-Georg Braun, Evelyn Meyer, Mingtai Wang Introduction Creation of Defined Micrometersized Patterns by Chemical Surface Heterogenisation Preparation of Ultrathin Micropatterned Amorphous Polyethylene Oxide (PEO) Layers by Controlled Dewetting on Heterogeneous Surfaces Characteristic Growth Patterns of PEO Lamellae on Micropatterned Surface Areas Basic Ideas on Diffusion Controlled Crystallisation Brandung Structures of PEO Crystallised in Ultrathin Micro-patterned Films Crystallisation of PEO in Microdroplets Obtained by Dewetting on Heterogeneous Surfaces Summary 250 References Vitrification and Devitrification of the Rigid Amorphous Fraction in Semicrystalline Polymers Revealed from Frequency Dependent Heat Capacity Christoph Schick, Andreas Wurm, Alaa Mohammed Introduction Determination of the Rigid Amorphous Fraction Experimental Results Discussion Conclusion 271 References Probing Crystallization Studying Amorphous Phase Evolution Tiberio A. Ezquerra, Aurora Nogales Introduction Brief Description of Dielectric Spectroscopy Influence of Crystallinity on the Segmental Relaxation Influence of Crystallinity on the Segmental Cooperativity Crystallization as Revealed by the Time Evolution of the Crystalline and the Amorphous Phases Lamellar Structure Formation Crystallization Induced Effects in the Amorphous Phase Combined Picture About Crystallization from the Structure-Dynamics Relationships Conclusions 294

7 XII Table of Contents 16 Modeling Polymer Crystallization: DSC Approach Joan Josep Sufiol Introduction Kinetic Analysis Specific Surface Energy Conclusions 308 References A Computational Model for Processing of Semicrystalline Polymers: The Effects of Flow-Induced Crystallization Gerrit W.M. Peters Introduction Modelling Balance Equations Constitutive Equations Results Conclusions 323 References Physical Cross Links in Amorphous PET, Influence of Cooling Rate and Ageing Stefano Piccarolo, Elena Vassileva, Zebene Kifiie Introduction Continuous Cooling Transformation (CCT) of PET Physical Cross Links vs Entanglements Sample Preparation and Test Procedure Isothermal Crystallization of Glassy PET Rejuvenation Procedure Results Conclusions 340 References Maximum Crystal Growth Rate and Its Corresponding State in Polymerie Materials Norimasa Okui, Susumu Umemoto Introduction Test of WLF and Arrhenius Expressions Master Curve for Crystal Growth Rate Molecular Weight Dependence of Crystal Growth Rate Effect of Super Cooling on the Molecular Weight Dependence of Growth Rate Molecular Weight Dependence of Maximum Crystal Growth Rate Relationship Between T and T cmax 357

8 Table of Contents XIII Ratio of AE and AH m Ratio of a and AH m Relationship Among Thermodynamic Transition Teniperatures Conclusions 363 References Lamellar Growth in Melt-Crystallizing Polymers: Some Effect Related to a Nucleating Agent Gaetano Di Marco, Marco Pieruccini Introduction Preliminary Analysis Thermodynamic Viewpoint Lattice Model SAXS Analysis Conchiding Rcmarks 376 References Outlook and Open Questions: A Personal View Günter Reiter, Jens-Uwe Sommer 378 Subject Index 383