Handbook of Polymer Crystallization

International team of experts reviews the latest developmentsin polymer crystallization

The complexity of polymer crystallization has posed along–standing challenge to the scientific community, demanding thedevelopment and application of a variety of microscopic,calorimetric, and spectroscopic experimental methods. By buildingour understanding of polymer crystallization, researchers havehelped fuel the advancement of nanoscience and nanotechnology.

Offering a comprehensive review of the field, Handbook ofPolymer Crystallization examines the latest discoveries,helping readers not only understand polymer crystallization, butalso take full advantage of the phenomenon in order to design newmaterials and develop new applications. The book also explores themany problems that can arise during the crystallization process,setting forth tested and proven solutions to achieve desiredresults.

Handbook of Polymer Crystallization featurescontributions from an international team of thermoplastic polymerscientists and covers such topics as:

Experimental techniques for studies of polymercrystallization Structure of crystalline polymers, kinetics of nucleation, andgrowth of the crystalline phase Molecular modeling of polymer crystallization andcrystallization kinetics Crystallization in copolymers, miscible and immiscible polymerblends, and polymer composites Crystallization under confinement Effect of flow on crystallization

Figures provided throughout the book help illustrate the coreprinciples and mechanisms of polymer crystallization. In addition,references at the end of each chapter guide readers to the primaryliterature in order to investigate individual topics in greaterdepth.

Examining the most important developments in polymercrystallization, this book is recommended for all thermoplasticpolymers researchers, offering them the foundation needed to maketheir own discoveries.

Preface xiii

Contributors xv

1 Experimental Techniques 1
Benjamin S. Hsiao, Feng Zuo, and Yimin Mao, ChristophSchick

1.1 Introduction, 1

1.2 Optical Microscopy, 2

1.2.1 Reflection and Transmission Microscopy, 2

1.2.2 Contrast Modes, 2

1.2.3 Selected Applications, 3

1.3 Electron Microscopy, 5

1.3.1 Imaging Principle, 5

1.3.2 Sample Preparation, 6

1.3.3 Relevant Experimental Techniques, 7

1.3.4 Selected Applications, 8

1.4 Atomic Force Microscopy, 9

1.4.1 Imaging Principle, 9

1.4.2 Scanning Modes, 9

1.4.3 Comparison between AFM and EM, 10

1.4.4 Recent Development: Video AFM, 10

1.4.5 Selected Applications, 10

1.5 Nuclear Magnetic Resonance, 12

1.5.1 Chemical Shift, 13

1.5.2 Relevant Techniques, 13

1.5.3 Recent Development: Multidimensional NMR, 14

1.5.4 Selected Applications, 14

1.6 Scattering Techniques: X–Ray, Light, and Neutron, 15

1.6.1 Wide–Angle X–Ray Diffraction, 15

1.6.2 Small–Angle X–Ray Scattering, 17

1.6.3 Small–Angle Light Scattering, 19

1.6.4 Small–Angle Neutron Scattering, 21

1.7 Differential Scanning Calorimetry, 22

1.7.1 Modes of Operation, 22

1.7.2 Determination of Degree of Crystallinity, 25

1.8 Summary, 25

Acknowledgments, 26

References, 26

2 Crystal Structures of Polymers 31
Claudio De Rosa and Finizia Auriemma

2.1 Constitution and Confi guration of Polymer Chains, 31

2.2 Conformation of Polymer Chains in Crystals andConformational Polymorphism, 33

2.3 Packing of Macromolecules in Polymer Crystals, 43

2.4 Symmetry Breaking, 49

2.5 Packing Effects on the Conformation of Polymer Chains in theCrystals: The Case of Aliphatic Polyamides, 50

2.6 Defects and Disorder in Polymer Crystals, 55

2.6.1 Substitutional Isomorphism of Different Chains, 56

2.6.2 Substitutional Isomorphism of Different Monomeric Units,57

2.6.3 Conformational Isomorphism, 58

2.6.4 Disorder in the Stacking of Ordered Layers (Stacking FaultDisorder), 58

2.7 Crystal Habits, 60

2.7.1 Rounded Lateral Habits, 66

Acknowledgments, 67

References, 67

3 Structure of Polycrystalline Aggregates 73
Buckley Crist

3.1 Introduction, 73

3.2 Crystals Grown from Solution, 75

3.2.1 Facetted Monolayer Crystals from Dilute Solution, 75

3.2.2 Dendritic Crystals from Dilute Solution, 81

3.2.3 Growth Spirals in Dilute Solution, 85

3.2.4 Concentrated Solutions, 92

3.3 Crystals and Aggregates Grown from Molten Films, 94

3.3.1 Structures in Thin Films, 94

3.3.2 Structures in Ultrathin Films, 98

3.3.3 Edge–On Lamellae in Molten Films, 102

3.4 Spherulitic Aggregates, 104

3.4.1 Optical Properties of Spherulites, 105

3.4.2 Occurrence of Spherulites, 108

3.4.3 Development of Spherulites, 110

3.4.4 Banded Spherulites and Lamellar Twist, 116

Acknowledgments, 121

References, 121

4 Polymer Nucleation 125
Kiyoka N. Okada and Masamichi Hikosaka

4.1 Introduction, 126

4.2 Classical Nucleation Theory, 126

4.2.1 Nucleation Rate (I), 126

4.2.2 Free Energy for Formation of a Nucleus G(N), 127

4.2.3 Free Energy for Formation of a Critical Nucleus( G∗), 127

4.2.4 Shape of a Nucleus Is Related to Kinetic Parameters,128

4.2.5 Diffusion, 128

4.3 Direct Observation of Nano–Nucleation by SynchrotronRadiation, 128

4.3.1 Introduction and Experimental Procedure, 128

4.3.2 Observation of Nano–Nucleation by SAXS, 128

4.3.3 Extended Guinier Plot Method and Iteration Method, 129

4.3.4 Kinetic Parameters and Size Distribution of theNano–Nucleus, 130

4.3.5 Real Image of Nano–Nucleation, 131

4.3.6 Supercooling Dependence of Nano–nucleation, 133

4.3.7 Relationship between Nano–Nucleation andMacro–Crystallization, 133

4.4 Improvement of Nucleation Theory, 135

4.4.1 Introduction, 135

4.4.2 Nucleation Theory Based on Direct Observation ofNucleation, 135

4.4.3 Confirmation of the Theory by Overall Crystallinity,137

4.5 Homogeneous Nucleation from the Bulk Melt under ElongationalFlow, 139

4.5.1 Introduction and Case Study, 139

4.5.2 Formulation of Elongational Strain Rate e, 139

4.5.3 Nano–Oriented Crystals, 140

4.5.4 Evidence of Homogeneous Nucleation, 144

4.5.5 Nano–Nucleation Results in Ultrahigh Performance, 147

4.6 Heterogeneous Nucleation, 148

4.6.1 Introduction, 148

4.6.2 Experimental, 149

4.6.3 Role of Epitaxy in Heterogeneous Nucleation, 150

4.6.4 Acceleration Mechanism of Nucleation of Polymers byNano–Sizing of Nucleating Agent, 153

4.7 Effect of Entanglement Density on the Nucleation Rate,156

4.7.1 Introduction and Experimental, 156

4.7.2 Increase of e Leads to a Decrease of I, 157

4.7.3 Change of e with t, 158

4.7.4 Two–Step Entangling Model, 159

4.8 Conclusion, 160

Acknowledgments, 161

References, 161

5 Growth of Polymer Crystals 165
Kohji Tashiro

5.1 Introduction, 165

5.1.1 Complex Behavior of Polymers, 165

5.2 Growth of Polymer Crystals from Solutions, 167

5.2.1 Single Crystals, 167

5.2.2 Crystallization from Solution under Shear, 168

5.2.3 Solution Casting Method, 168

5.3 Growth of Polymer Crystals from Melt, 169

5.3.1 Positive and Negative Spherulites, 169

5.3.2 Spherulite Morphology and Crystalline Modification,170

5.3.3 Spherulite Patterns of Blend Samples, 172

5.4 Crystallization Mechanism of Polymer, 173

5.4.1 Basic Theory of Crystallization of Polymer, 173

5.4.2 Growth Rate of Spherulites, 177

5.5 Microscopically Viewed Structural Evolution in the GrowingPolymer Crystals, 178

5.5.1 Experimental Techniques, 178

5.5.2 Structural Evolution in Isothermal Crystallization,179

5.5.3 Shear–Induced Crystallization of the Melt, 186

5.6 Crystallization upon Heating from the Glassy State, 189

5.6.1 Cold Crystallization, 189

5.6.2 Solvent–Induced Crystallization of Polymer Glass, 189

5.7 Crystallization Phenomenon Induced by Tensile Force, 191

5.8 Photoinduced Formation and Growth of Polymer Crystals,191

5.9 Conclusion, 192

References, 193

6 Computer Modeling of Polymer Crystallization 197
Gregory C. Rutledge

6.1 Introduction, 197

6.2 Methods, 198

6.2.1 Molecular Dynamics, 199

6.2.2 Langevin Dynamics, 200

6.2.3 Monte Carlo, 200

6.2.4 Kinetic Monte Carlo, 201

6.3 Single–Chain Behavior in Crystallization, 202

6.3.1 Solid–on–Solid Models, 202

6.3.2 Molecular and Langevin Dynamics, 203

6.4 Crystallization from the Melt, 204

6.4.1 Lattice Monte Carlo Simulations, 205

6.4.2 Molecular Dynamics Using Coarse–Grained Models, 206

6.4.3 Molecular Dynamics Using Atomistic Models, 207

6.5 Crystallization under Deformation or Flow, 208

6.6 Concluding Remarks, 210

References, 211

7 Overall Crystallization Kinetics 215
Ewa Piorkowska and Andrzej Galeski

7.1 Introduction, 215

7.2 Measurements, 216

7.3 Simulation, 217

7.4 Theories: Isothermal and Nonisothermal Crystallization,218

7.4.1 Introductory Remarks, 218

7.4.2 Extended Volume Approach, 218

7.4.3 Probabilistic Approaches, 220

7.4.4 Isokinetic Model, 223

7.4.5 Rate Equations, 223

7.5 Complex Crystallization Conditions: General Models, 224

7.6 Factors Influencing the Overall Crystallization Kinetics,224

7.6.1 Crystallization in a Uniform Temperature Field, 224

7.6.2 Crystallization in a Temperature Gradient, 225

7.6.3 Crystallization in a Confi ned Space, 226

7.6.4 Flow–Induced Crystallization, 228

7.7 Analysis of Crystallization Data, 230

7.7.1 Isothermal Crystallization, 230

7.7.2 Nonisothermal Crystallization, 231

7.8 Conclusions, 233

References, 234

8 Epitaxial Crystallization of Polymers: Means and Issues237
Annette Thierry and Bernard A. Lotz

8.1 Introduction and History, 237

8.2 Means of Investigation of Epitaxial Crystallization, 239

8.2.1 Global Techniques, 239

8.2.2 Thin Film Techniques, 239

8.2.3 Sample Preparation Techniques, 240

8.2.4 Other Samples and Investigation Procedures, 241

8.3 Epitaxial Crystallization of Polymers, 241

8.3.1 General Principles, 241

8.3.2 Epitaxial Crystallization of Linear Polymers, 243

8.3.3 Epitaxy of Helical Polymers, 245

8.3.4 Polymer/Polymer Epitaxy, 250

8.4 Epitaxial Crystallization: Further Issues and Examples,252

8.4.1 Topographic versus Lattice Matching, 252

8.4.2 Epitaxy of Isotactic Polypropylene on IsotacticPolyvinylcyclohexane, 254

8.4.3 Epitaxy Involving Fold Surfaces of Polymer Crystals,254

8.5 Epitaxial Crystallization: Some Issues and Applications,256

8.5.1 Epitaxial Crystallization and the Design of New NucleatingAgents, 256

8.5.2 Epitaxial Crystallization and the Design of CompositeMaterials, 257

8.5.3 Conformational and Packing Energy Analysis of PolymerEpitaxy, 258

8.5.4 Epitaxy as a Means to Generate Oriented Opto– orElectroactive Materials, 259

8.6 Conclusions, 260

References, 262

9 Melting 265
Marek Pyda

9.1 Introduction to the Melting of Polymer Crystals, 265

9.2 Parameters of the Melting Process, 267

9.3 Change of Conformation, 268

9.4 Heat of Fusion and Degree of Crystallinity, 270

9.4.1 Heat of Fusion, 270

9.4.2 Degree of Crystallinity, 272

9.5 Equilibrium Melting, 274

9.5.1 The Equilibrium Melting Temperature, 274

9.5.2 The Equilibrium Thermodynamic Functions, 275

9.6 Other Factors Affecting the Melting Process of PolymerCrystals, 277

9.6.1 The Influence of the Polymer s Chemical Structure onthe Melting Process, 277

9.6.2 The Effect of Polymer Molar Mass on the Melting Behavior,277

9.6.3 Influence of Heating Rate on the Melting, 278

9.6.4 Multiple Melting Peaks of Polymers, 279

9.6.5 Influence of Pressure on the Melting Process, 281

9.6.6 The Melting Process by Other Methods, 281

9.6.7 Diluents Effect: The Influence of Small Diluents on theMelting Process, 282

9.7 Irreversible and Reversible Melting, 282

9.8 Conclusions, 284

References, 285

10 Crystallization of Polymer Blends 287
Mariano Pracella

10.1 General Introduction, 287

10.2 Thermodynamics of Polymer Blends, 288

10.2.1 General Principles, 288

10.3 Miscible Polymer Blends, 290

10.3.1 Introduction, 290

10.3.2 Phase Morphology, 291

10.3.3 Crystal Growth Rate, 292

10.3.4 Overall Crystallization Kinetics, 294

10.3.5 Melting Behavior, 295

10.3.6 Blends with Partial Miscibility, 296

10.3.7 Crystallization Behavior of Amorphous/Crystalline Blends,297

10.3.8 Crystallization Behavior of Crystalline/CrystallineBlends, 298

10.4 Immiscible Polymer Blends, 303

10.4.1 Introduction, 303

10.4.2 Morphology and Crystal Nucleation, 303

10.4.3 Crystal Growth Rate, 304

10.4.4 Crystallization Behavior of Immiscible Blends, 305

10.5 Compatibilized Polymer Blends, 307

10.5.1 Compatibilization Methods, 307

10.5.2 Morphology and Phase Interactions, 308

10.5.3 Crystallization Behavior of Compatibilized Blends,311

10.6 Polymer Blends with Liquid–Crystalline Components, 314

10.6.1 Introduction, 314

10.6.2 Mesomorphism and Phase Transition Behavior of LiquidCrystals and Liquid Crystal Polymers, 314

10.6.3 Crystallization Behavior of Polymer/LC Blends, 316

10.6.4 Crystallization Behavior of Polymer/LCP Blends, 317

10.7 Concluding Remarks, 320

Abbreviations, 321

References, 322

11 Crystallization in Copolymers 327
Sheng Li and Richard A. Register

11.1 Introduction, 327

11.2 Crystallization in Statistical Copolymers, 328

11.2.1 Flory s Model, 328

11.2.2 Solid–State Morphology, 330

11.2.3 Mechanical Properties, 334

11.2.4 Crystallization Kinetics, 335

11.2.5 Statistical Copolymers with Two Crystallizable Units,337

11.2.6 Crystallization Thermodynamics, 337

11.3 Crystallization of Block Copolymers from Homogeneous orWeakly Segregated Melts, 340

11.3.1 Solid–State Morphology, 340

11.3.2 Crystallization–Driven Structure Formation, 342

11.4 Summary, 343

References, 344

12 Crystallization in Nano–Confi ned Polymeric Systems347
Alejandro J. Müller, Maria Luisa Arnal, and Arnaldo T.Lorenzo

12.1 Introduction, 347

12.2 Confined Crystallization in Block Copolymers, 348

12.2.1 Crystallization within Diblock Copolymers that areStrongly Segregated or Miscible and Contain only One CrystallizableComponent, 351

12.2.2 Crystallization within Strongly SegregatedDouble–Crystalline Diblock Copolymers and Triblock Copolymers,355

12.3 Crystallization of Droplet Dispersions and Polymer Layers,361

12.4 Polymer Blends, 368

12.4.1 Immiscible Polymer Blends, 368

12.4.2 Melt Miscible Blends, 371

12.5 Modeling of Confi ned Crystallization of Macromolecules,371

12.6 Conclusions, 372

References, 372

13 Crystallization in Polymer Composites and Nanocomposites379
Ewa Piorkowska

13.1 Introduction, 379

13.2 Microcomposites with Particulate Fillers, 380

13.3 Fiber–Reinforced Composites, 382

13.4 Modeling of Crystallization in Fiber–Reinforced Composites,385

13.5 Nanocomposites, 388

13.6 Conclusions, 393

Appendix, 393

References, 394

14 Flow–Induced Crystallization 399
Gerrit W.M. Peters, Luigi Balzano, and Rudi J.A.Steenbakkers

14.1 Introduction, 399

14.2 Shear–Induced Crystallization, 401

14.2.1 Nature of Crystallization Precursors, 405

14.3 Crystallization during Drawing, 407

14.3.1 Spinning, 408

14.3.2 Elongation–Induced Crystallization; Lab Conditions,409

14.4 Models of Flow–Induced Crystallization, 410

14.4.1 Flow–Enhanced Nucleation, 411

14.4.2 Flow–Induced Shish Formation, 419

14.4.3 Application to Injection Molding, 421

14.5 Concluding Remarks, 426

References, 427

15 Crystallization in Processing Conditions 433
Jean–Marc Haudin

15.1 Introduction, 433

15.2 General Effects of Processing Conditions onCrystallization, 433

15.2.1 Effects of Flow, 433

15.2.2 Effects of Pressure, 435

15.2.3 Effects of Cooling Rate, 436

15.2.4 Effects of a Temperature Gradient, 437

15.2.5 Effects of Surfaces, 439

15.3 Modeling, 440

15.3.1 General Framework, 440

15.3.2 Simplifi ed Expressions, 441

15.3.3 General Systems of Differential Equations, 441

15.4 Crystallization in Some Selected Processes, 442

15.4.1 Cast Film Extrusion, 442

15.4.2 Fiber Spinning, 445

15.4.3 Film Blowing, 448

15.4.4 Injection Molding, 454

15.5 Conclusion, 458

References, 459

Index 463

DR. EWA PIORKOWSKA, is Professor and the Head of theDepartment of Polymer Structure at the Centre of Molecular andMacromolecular Studies, Polish Academy of Sciences, Poland. Herresearch interests include crystallization, structure andproperties of polymers, polymer blends, composites andnanocomposites.

DR. GREGORY C. RUTLEDGE, is the Lammot du Pont Professorin the Department of Chemical Engineering at the MassachusettsInstitute of Technology. His research interests include polymerscience and engineering, statistical thermodynamics, molecularsimulation, and nanotechnology.