Rubber–Clay Nanocomposites: Science, Technology, and Applications

The one–stop resource for rubber–clay nanocomposite information
The first comprehensive, single–volume book to compile all the most important data on rubber–clay nanocomposites in one place, Rubber–Clay Nanocomposites: Science, Technology, and Applications reviews rubber–clay nanocomposites in an easy–to–reference format designed for R&D professionals.
Including contributions from experts from North America, Europe, and Asia, the book explores the properties of compounds with rubber–clay nanocomposites, including their rheology, curing kinetics, mechanical properties, and many others.
Rubber–clay nanocomposites are of growing interest to the scientific and technological community, and have been shown to improve rubber compound reinforcement and impermeability. These natural mineral fillers are of potential interest for large–scale applications and are already making an impact in several major fields. Packed with valuable information about the synthesis, processing, and mechanics of these reinforced rubbers, the book covers assorted rubber–clay nanocomposites applications, such as in automotive tires and as polymer fillers.
Promoting common knowledge and interpretation of the most important aspects of rubber–clay nanocomposites, and clarifying the main results achieved in the field of rubbers and crosslinked rubbers—something not covered in other books in the field—Rubber–Clay Nanocomposites helps scientists understand morphology, vulcanization, permeability, processing methods, and characterization factors quickly and easily.

Spis treści:
PREFACE xvii
CONTRIBUTORS xxi
SECTION I CLAYS FOR NANOCOMPOSITES
1 CLAYS AND CLAY MINERALS 3
1.1 What’s in a Name / 3
1.2 Multiscale Organization of Clay Minerals / 6
1.2.1 Dispersion Versus Aggregation / 6
1.2.2 Delamination/Exfoliation Versus Sta cking / 6
1.3 Intimate Organization of the Layer / 8
1.3.1 Cationic and Neutral Clay Minerals / 8
1.3.2 Anionic Clay Minerals (O) / 21
1.4 Most Relevant Physicochemical Properties of Clay Mineral / 22
1.4.1 Surface Area and Porosity / 22
1.4.2 Chemical Landscape of the Clay Surfaces / 24
1.4.3 Cation (and Anion) Exchange Capacity / 24
1.4.4 Intercalation and Confinement in the Interlayer Space / 27
1.4.5 Swelling / 30
1.4.6 Rheology / 31
1.5 Availability of Natural Clays and Synthetic Clay Minerals / 33
1.6 Clays and (Modified) Clay Minerals as Fillers / 35
Acknowledgment / 37
References / 37
2 ORGANOPHILIC CLAY MINERALS 45
2.1 Organophilicity/Lipophilicity and the Hydrophilic/Lipophilic Balance (HLB) / 45
2.2 From Clays to Organoclays in Polymer Technology / 47
2.3 Methods of Organoclay Synthesis / 49
2.3.1 Cation Exchange from Solutions / 49
2.3.2 Solid–State Intercalation / 58
2.3.3 Grafting from Solution / 59
2.3.4 Direct Synthesis of Grafted Organoclays / 62
2.3.5 Postsynthesis Modifications of Organoclays: The “PCH” / 64
2.3.6 An Overview of Commercial Organoclays / 64
2.3.7 One–Pot CPN Formation / 66
2.4 Other Types of Clay Modifications for Clay–Based Nanomaterials / 66
2.4.1 Organo–Pillared Clays / 66
2.4.2 Plasma–Treated Clays / 69
2.5 Fine–Tuning of Organoclays Properties / 69
2.5.1 Maximizing the Dispersion of the Filler: Effect
of Surfactant/CEC Ratio / 69
2.5.2 Improving Thermal Stability / 70
2.5.3 Chemical Treatments / 71
2.5.4 Physical Treatments (Freeze–Drying, Sonication, Microwave) / 71
2.6 Some Introductory Reflections on Organoclay Polymer Nanocomposites / 72
References / 75
3 INDUSTRIAL TREATMENTS AND MODIFICATION OF CLAY MINERALS 87
3.1 Bentonite: From Mine to Plant / 87
3.1.1 A Largely Diffused Clay / 87
3.1.2 Geological Occurrence / 89
3.1.3 Mining / 89
3.2 Proce ssing of Bentonite / 90
3.2.1 Modification of Bentonite Properties / 90
3.2.2 Processing Technologies / 91
3.3 Purification of Clay / 93
3.3.1 Influence of Clay Concentration / 94
3.3.2 Influence of Swelling Time / 94
3.3.3 Influence of Temperature / 95
3.4 Reaction of Clay with Organic Substances / 97
3.5 Particle Size Modification / 99
References / 99
4 ALKYLAMMONIUM CHAINS ON LAYERED CLAY MINERAL SURFACES 101
4.1 Structure and Dynamics / 101
4.1.1 Packing Density and Self–Assembly / 102
4.1.2 Dynamics and Diffusion at the Clay–Surfactant Interface / 110
4.1.3 Utility of Molecular Simulation to Obtain Molecular–Level Insight / 111
4.2 Thermal Properties / 111
4.2.1 Reversible Melting Transitions of Alkyl Chains in the Interlayer / 111
4.2.2 Solvent Evaporation and Thermal Elimination of Alkyl Surfactants / 113
4.3 Layer Separation and Miscibility with Polymers / 115
4.3.1 Thermodynamics Model for Exfoliation in Polymer Matrices / 115
4.3.2 Cleavage Energy / 116
4.3.3 Surface Energy / 121
4.4 Mechanical Properties of Clay Minerals / 121
References / 123
5 CHEMISTRY OF RUBBER–ORGANOCLAY NANOCOMPOSITES 127
5.1 Introduction / 127
5.2 Organic Cation Decomposition in Salts, Organoclays and Polymer Nanocomposites / 128
5.2.1 Experimental Techniques / 128
5.2.2 Decomposition of Organoclays Versus Precursor Organic Cation Salts / 133
5.3 Mechanism of Thermal Decomposition of Organoclays / 135
5.4 Role of Organic Cations in Organoclays as Rubber Vulcanization Activators / 137
References / 141
SECTION II PREPARATION AND CHARACTERIZATION OF RUBBER–CLAY NANOCOMPOSITES
6 PROCESSING METHODS FOR THE PREPARATION OF RUBBER–CLAY NANOCOMPOSITES 147
6.1 Introduction / 147
6.2 Latex Compounding Method / 148
6.2.1 Mechanism / 148
6.2.2 Influencing Factors / 149
6.3 Melt Compounding / 157
6.3.1 Mechanism / 157
6.3.2 Influencing Facto rs / 160
6.4 Solution Intercalation and In Situ Polymerization Intercalation / 170
6.5 Summary and Prospect / 170
Acknowledgment / 171
References / 171
7 MORPHOLOGY OF RUBBER–CLAY NANOCOMPOSITES 181
7.1 Introduction / 181
7.1.1 Focus, Objective and Structure of Chapter 7 / 181
7.1.2 X–Ray Diffraction Analysis for the Investigation of RCN / 182
7.2 Background for the Review of RCN Morphology / 182
7.2.1 Cationic Clays Used for the Preparation of Rubber Nanocomposites / 182
7.2.2 Multiscale Organization of Layered Clays / 184
7.2.3 Clay Distribution and Dispersion / 184
7.2.4 Clay Modification: Intercalation of Low Molecular Mass Substances / 184
7.2.5 Types of Polymer–Clay Composites / 184
7.2.6 Specific Literature on RCN / 186
7.3 Rubber–Clay Nanocomposites with Pristine Clays / 186
7.3.1 Rubber Nanocomposites with Cationic Clays / 187
7.3.2 In a Nutshell / 187
7.3.3 Distribution and Dispersion of a Pristine Clay in a Rubber Matrix / 190
7.3.4 Organization of Aggregated Pristine Clays / 194
7.4 Rubber–Clay Nanocomposites with Clays Modified with Primary Alkenylamines / 197
7.4.1 In a Nutshell / 197
7.4.2 Composites with Montmorillonite and Bentonite / 198
7.4.3 Composites with Fluorohectorite Modified with a Primary Alkenylamine / 202
7.5 Rubber–Clay Nanocomposites with Clays Modified with an Ammonium Cation Having three Methyls and One Long–Chain Alkenyl Substituents / 206
7.5.1 In a Nutshell / 206
7.5.2 Composites with Montmorillonite and Bentonite / 207
7.6 Rubber–Clay Nanocomposites with Montmorillonite Modified with Two Substituents Larger Than Methyl / 212
7.6.1 In a Nutshell / 212
7.6.2 Hydrogenated Tallow and Benzyl Groups as Ammonium Cation Substituents / 213
7.6.3 Hydrogenated Tallow and Ethylhexyl Groups as Ammonium Cation Substituents / 213
7.6.4 Other Long– and Short–Chain Alkenyl Groups as Ammonium Cation Substituents / 215
7.7 Rubber Composites with Montmorillonite Modified with an Ammonium Cation Containing a Polar Group / 215
7.7.1 In a Nutshell / 217
7.7.2 Composites with Diene Rubbers / 217
7.8 Rubber Nanocomposites with Montmorillonite Modified with an Ammonium Cation Containing Two Long–Chain Alkenyl Substituents / 219
7.8.1 In a Nutshell / 220
7.8.2 Composites with Two Talloyl Groups as Ammonium Cation Substituents / 220
7.9 Proposed Mechanisms for the Formation of Rubber–Clay Nanocomposites / 228
7.9.1 Two Mechanisms for the Formation of an Exfoliated Clay / 228
7.9.2 Two Mechanisms for the Formation of an Intercalated Organoclay / 228
7.9.3 Intercalation of Polymer Chains in the Interlayer Space / 229
7.9.4 Intercalation of Low Molecular Mass Substances in the Interlayer Space / 230
Abbreviations / 232
Acknowledgment / 233
References / 233
8 RHEOLOGY OF RUBBER–CLAY NANOCOMPOSITES 241
8.1 Introduction / 241
8.2 Rheological Behavior of Rubber–Clay Nanocomposites / 242
8.2.1 Natural Rubber (NR), Epoxidized Natural Rubber (ENR) and Polyisoprene Rubber (IR)–Clay Nanocomposites / 243
8.2.2 Styrene–Butadiene Rubber (SBR)–Clay Nanocomposites / 246
8.2.3 Polybutadiene Rubber (BR)–Clay Nanocomposites / 247
8.2.4 Acrylonitrile Butadiene Rubber (NBR)–Clay Nanocomposites / 250
8.2.5 Ethylene Propylene Rubber–Clay Nanocomposites / 253
8.2.6 Fluoroelastomer–Clay Nanocomposites / 254
8.2.7 Poly(isobutylene–co–para–methylstyrene) (BIMS) Rubber–Clay Nanocomposites / 257
8.2.8 Poly(ethylene–co–vinylacetate) (EVA) Rubber–Clay Nanocomposites / 257
8.2.9 Polyepichlorohydrin Rubber–Clay Nanocomposites / 259
8.2.10 Thermoplastic Polyurethane (TPU)–Clay Nanocomposites / 261
8.2.11 Styrene–Ethylene–Butylene–Styrene (SEBS) Block Copolymer–Clay Nanocom posites / 262
8.3 General Remarks on Rheology of Rubber–Clay Nanocomposites / 263
8.4 Overview of Rheological Theories of Polymer–Clay Nanocomposites / 269
8.5 Conclusion and Outlook / 270
References / 271
9 VULCANIZATION CHARACTERISTICS AND CURING KINETIC OF RUBBER–ORGANOCLAY NANOCOMPOSITES 275
9.1 Introduction / 275
9.2 Vulcanization Reaction / 276
9.3 Rubber Cross–Linking Systems / 278
9.3.1 Sulfur Vulcanization / 278
9.3.2 Peroxide Vulcanization / 282
9.4 The Role of Organoclay on Vulcanization Reaction / 283
9.4.1 Influence of Organoclay Structural Characteristics on Rubber Vulcanization / 288
9.5 Vulcanization Kinetics of Rubber–Organoclay Nanocomposites / 290
9.6 Conclusions / 297
References / 298
10 MECHANICAL AND FRACTURE MECHANICS PROPERTIES OF RUBBER COMPOSITIONS WITH REINFORCING COMPONENTS 305
10.1 Introduction / 305
10.2 Testing of Viscoelastic and Mechanical Properties of Reinforced Elastomeric Materials / 307
10.2.1 Dynamic–Mechanical Analysis / 307
10.2.2 Tensile Testing / 310
10.2.3 Assessment of Toughness Behavior under Impact–Like Loading Conditions / 313
10.2.4 Hardness Testing / 315
10.2.5 Special Methods / 316
10.3 Characterization of the Fracture Behavior of Elastomers / 319
10.3.1 Fracture Mechanics Concepts / 319
10.3.2 Experimental Methods / 321
10.4 Mechanism of Reinforcement in Rubber–Clay Composites / 328
10.5 Theories and Modeling of Reinforcement / 333
Acknowledgment / 336
References / 336
11 PERMEABILITY OF RUBBER COMPOSITIONS CONTAINING CLAY 343
11.1 Introduction / 343
11.1.1 Butyl Rubbers as Nanocomposite Base Elastomers / 343
11.1.2 Measurement of Tire Innerliner Compound Permeability / 345
11.1.3 Further Improvement in Tire Permeability / 346
11.2 Nanocomposites / 346
11.3 Preparation of Elastomer Nanocomposites / 352
11.4 Temperature and Compound Permeability / 352
1 1.5 Vulcanization of Nanocomposite Compounds and Permeability / 356
11.6 Thermodynamics and BIMSM Montmorillonite Nanocomposites / 358
11.7 Nanocomposites and Tire Performance / 362
11.8 Summary / 364
References / 364
SECTION III COMPOUNDS WITH RUBBER–CLAY NANOCOMPOSITES
12 RUBBER–CLAY NANOCOMPOSITES BASED ON APOLAR DIENE RUBBER 369
12.1 Introduction / 369
12.2 Preparation Methods / 371
12.2.1 Latex / 371
12.2.2 Solution / 373
12.2.3 Melt Blending / 374
12.3 Cure Characteristics / 377
12.4 Clay Dispersion / 379
12.4.1 Detection / 380
12.4.2 Characterization / 383
12.5 Properties / 387
12.5.1 Mechanical (Dynamic–Mechanical) / 387
12.5.2 Friction/Wear/Abrasion / 392
12.5.3 Barrier / 393
12.5.4 Fire Resistance / 396
12.5.5 Others / 397
12.6 Applications and Future Trends / 398
Acknowledgment / 399
References / 399
13 RUBBER–CLAY NANOCOMPOSITES BASED ON NITRILE
RUBBER 409
13.1 Introduction / 409
13.2 Preparation Methods and Clay
Dispersion / 410
13.2.1 Solution / 410
13.2.2 Latex / 411
13.2.3 Melt Blending / 412
13.3 Cure Characteristics / 414
13.4 Properties / 416
13.4.1 Mechanical (Dynamic–Mechanical) / 416
13.4.2 Friction/Wear / 421
13.4.3 Barrier / 423
13.4.4 Fire Resistance / 424
13.4.5 Others / 425
13.5 Outlook / 425
Acknowledgment / 426
References / 426
xii CONTENTS
FOR SCREEN VIEWING IN DART ONLY
14 RUBBER–CLAY NANOCOMPOSITES BASED ON BUTYL AND
HALOBUTYL RUBBERS 431
14.1 Introduction / 431
14.1.1 Butyl Rubber: Key Properties
and Applications / 431
14.1.2 Butyl Rubber–Clay Nanocomposites / 433
14.2 Types of Clays Useful in Butyl Rubber–Clay
Nanocomposites / 435
14.2.1 Montmorillonite Clays / 435
14.2.2 Hydrotalcite Clays / 435
14.2.3 High Aspect Ratio Talc Fillers / 436
14.2.4 Other Clays / 437
14.3 Compatibilizer Systems for Butyl Rubber–Cl ay
Nanocomposites / 438
14.3.1 Surfactants and Swelling Agents / 439
14.3.2 Butyl Rubber Ionomers / 439
14.3.3 Maleic Anhydride–Grafted Polymers / 443
14.3.4 Low Molecular Weight Polymers and Resins / 444
14.4 Methods of Preparation of Butyl Rubber–Clay Nanocomposites / 444
14.4.1 Melt Method / 445
14.4.2 Solution Method / 445
14.4.3 Latex Method / 447
14.4.4 In Situ Polymerization / 448
14.5 Properties and Applications of Butyl Rubber–Clay Nanocomposites / 449
14.5.1 Air Barrier Properties / 449
14.5.2 Reinforcement Properties / 452
14.5.3 Vulcanization Properties / 454
14.5.4 Adhesion Properties / 456
14.5.5 Other Properties / 457
14.6 Conclusions / 457
References / 458
15 RUBBER–CLAY NANOCOMPOSITES BASED ON OLEFINIC RUBBERS (EPM, EPDM) 465
15.1 Introduction / 465
15.2 Types of Clay Minerals Useful in EPM–, EPDM–Clay Nanocomposites / 466
15.3 Compatibilizer Systems for Olefinic Rubber–Clay Nanocomposites / 467
15.4 Preparation of EPDM–Clay Nanocomposites by an In Situ Intercalation Method / 469
15.5 Characteristics of EPDM–Clay Nanocomposites / 473
15.5.1 Gas Barrier Properties of EPDM–Clay Nanocomposites / 473
15.5.2 Rheological Properties of EPDM–Clay Nanocomposites / 474
15.5.3 Stability of EPDM–Clay Nanocomposites / 475
15.5.4 Swelling Properties of EPDM–Clay Nanocomposites / 475
15.5.5 Mechanical Properties of EPDM–Clay Nanocomposites / 476
15.6 Preparation and Characteristics of EPM–Clay Nanocomposites / 479
15.6.1 Tensile Properties of EPM–CNs / 480
15.6.2 Temperature Dependence of Dynamic Storage Moduli of EPM–CNs / 481
15.6.3 Creep Properties of EPM–CNs / 482
15.6.4 Swelling Properties of EPM–CNs / 483
15.7 Conclusions / 486
References / 486
16 RUBBER–CLAY NANOCOMPOSITES BASED ON THERMOPLASTIC ELASTOMERS 489
16.1 Introductio