Physical Test Methods for Elastomers (eBook)

Roger Brown is an internationally acknowledged expert on physical testing and quality assurance of polymers and has published more than 70 technical papers and several books on testing subjects. He was responsible for Rapra's testing laboratories and services for 25 years and is editor of the journal Polymer Testing. He is active in many standards committees and is leader of the British delegation to ISO Technical Committee 45. Roger and his wife Yoland have opened their garden at Brownhill House for the National Garden Scheme for 33 years. They also enjoy driving their 4 kit cars.

Preface 5
Contents 7
Part I: Before You Test 15
Chapter 1: Introduction 16
1.1 Scope and Content 16
References 20
Chapter 2: General Considerations 21
2.1 Philosophy 21
2.2 Test Piece History 24
2.3 Test Conditions 25
2.4 Statistics 26
2.5 Sampling 27
2.6 Limitations of Results 29
2.7 Quality Systems 29
2.8 Test Equipment 33
2.9 Thermoplastic Elastomers 34
2.10 Product Testing 35
References 37
Chapter 3: Standards 39
3.1 Standards 39
3.1.1 Types of Standard 39
3.1.2 Test Methods 40
3.2 Organisations Producing Standards 42
3.2.1 Sources of Standards 42
3.2.2 International Standards 42
3.2.2.1 The International Organisation for Standardisation 42
3.2.2.2 Other International Standards 45
3.2.2.3 European Standards 46
3.2.3 National Standards 46
3.2.3.1 General 46
3.2.3.2 The British Standards Institution 47
3.2.3.3 Other British Standards 48
3.2.3.4 USA Standards 48
3.2.4 Company Standards 49
3.3 Units 50
References 50
Chapter 4: Conditioning and Test Atmospheres 52
4.1 Introduction 52
4.2 Storage 52
4.3 Conditioning 53
4.4 Test Conditions 55
4.5 Apparatus for Conditioning 56
4.5.1 Air Conditioned Rooms 56
4.5.2 Enclosures 57
4.5.3 Hygrometers 57
4.5.4 Thermometers 58
4.5.5 Apparatus for Elevated and Subnormal Temperatures 58
4.6 Mechanical Conditioning 59
References 61
Part II: Processing and Preparation for Test 63
Chapter 5: Processability 64
5.1 Introduction 64
5.2 Standard Methods for Particular Polymers 65
5.3 Sample Preparation 65
5.4 Viscoelastic Flow Behaviour 66
5.4.1 Introduction 66
5.4.2 Compression Plastimeters 68
5.4.3 Plasticity Retention Index 71
5.4.4 Rotation Plastimeters 72
5.4.5 Extrusion Rheometers 76
5.4.6 Mixing Machines 77
5.4.7 Other Processability Tests 78
5.4.8 Correlation Between Plastimeters 79
5.5 Scorch and Cure Rate 81
5.5.1 Introduction 81
5.5.2 Types of Curemeter 82
5.5.3 Extended Use of Curemeter Type Instruments 86
5.5.4 Alternative Methods 87
5.6 Tack 87
5.7 Other Tests 88
References 89
Chapter 6: Preparation of Test Pieces 93
6.1 Introduction 93
6.2 Mixing and Moulding 93
6.3 Cutting from Sheet 96
6.4 Test Pieces from Finished Products 98
References 100
Chapter 7: Mass, Density and Dimensions 101
7.1 Introduction 101
7.2 Mass 102
7.3 Density 102
7.4 Dimensions 105
7.4.1 Dimensions Needed 105
7.4.2 Standard Methods 105
7.4.3 Non-standard Methods 107
7.4.4 Surface Roughness 108
7.4.5 Extensometry 108
7.4.6 Dimensional Stability 109
7.4.7 Dispersion 109
References 112
Part III: Short Term Mechanical Properties 114
Chapter 8: Stress and Strain Data 115
8.1 Introduction 115
8.2 Stress/Strain Relationships 116
8.3 Poisson´s Ratio 120
8.4 Data for Finite Element Analysis 120
References 123
Chapter 9: Hardness 125
9.1 What Is Hardness? 125
9.2 Introduction to Rubber Hardness Tests 126
9.3 Dead Load Tests 128
9.3.1 IRHD Method, Normal Scale 128
9.3.2 High and Low Scales 130
9.3.3 Micro Tests 130
9.3.4 Apparent Hardness 132
9.3.5 British and ASTM standards 133
9.4 Durometer Tests 134
9.5 Nano and Dynamic Methods 137
9.6 Accuracy and Comparison of Hardness Tests 137
9.7 Use of Hardness Tests 140
References 140
Chapter 10: Tension 142
10.1 Introduction 142
10.2 Form of Test Piece 143
10.3 Measurement of Test Pieces 146
10.4 Apparatus 147
10.4.1 Tensile Machine 147
10.4.2 Grips 148
10.4.3 Application of Force 148
10.4.4 Force Measurement 150
10.4.5 Elongation Measurement 150
10.5 Calculation and Expression of Results 154
10.6 Relaxed Modulus 156
10.7 Biaxial Extension 156
References 158
Chapter 11: Compression 160
11.1 Introduction 160
11.2 Test Methods 163
11.3 Bulk Compression 164
References 165
Chapter 12: Shear and Flexure 166
12.1 Introduction 166
12.2 Simple Shear 166
12.3 Pure Shear 168
12.4 Torsion 169
12.5 Flexure 170
References 170
Chapter 13: Tear 171
13.1 Introduction 171
13.2 Forms of Test Piece 172
13.3 Preparation of Test Pieces 174
13.4 Measurement of Tearing Force 174
13.5 Expression of Results 176
13.6 Fracture Mechanics Approach 177
13.7 Cutting Resistance 179
References 180
Part IV: Time Dependent Properties 181
Chapter 14: Dynamic Stress and Strain 182
14.1 Principles of Dynamic Tests 182
14.2 Rebound Resilience 189
14.2.1 Principle 189
14.2.2 Pendulum Methods 190
14.2.3 Falling Weight Methods 192
14.3 Free Vibration Methods 193
14.3.1 Introduction 193
14.3.2 Yerzley Oscillograph 194
14.3.3 Torsion Pendulum 195
14.4 Forced Vibration Methods 198
14.4.1 Introduction 198
14.4.2 Brief Review of Forced Vibration Apparatus 199
14.4.3 Standard Methods 203
14.5 Comparison of Dynamic Methods 203
References 205
Chapter 15: Creep, Relaxation and Set 207
15.1 Introduction 207
15.2 Creep 208
15.3 Stress Relaxation 210
15.3.1 Introduction 210
15.3.2 Standard Methods in Compression 211
15.3.3 Apparatus 214
15.3.4 Use of Stress Relaxation Data 216
15.4 Set 217
15.4.1 Principle 217
15.4.2 Tests in Compression 219
15.4.3 Tests in Tension 220
References 222
Part V: Physical Properties 224
Chapter 16: Electrical Properties 225
16.1 Introduction 225
16.2 Resistance and Resistivity 226
16.2.1 General 226
16.2.2 Tests on Insulating Rubbers 227
16.2.3 Tests on Conducting and Anti-static Rubbers 231
16.3 Surface Charge 234
16.4 Electric Strength 235
16.5 Tracking Resistance 236
16.6 Permittivity and Power Factor 236
References 238
Chapter 17: Thermal Properties 241
17.1 Introduction 241
17.2 Thermal Analysis 242
17.3 Specific Heat 243
17.4 Thermal Conductivity and Diffusivity 244
17.4.1 Introduction 244
17.4.2 Thermal Conductivity 245
17.4.3 Thermal Diffusivity 248
17.5 Surface Heat Transfer Coefficient 249
References 249
Chapter 18: Permeability 252
18.1 Basic Theory 252
18.2 Gas Permeability 254
18.2.1 General 254
18.2.2 Differential Pressure Methods 254
18.2.3 Equal Pressure Methods 256
18.2.4 High Pressure Measurements 258
18.3 Vapour Permeability 258
References 261
Part VI: Durability 264
Chapter 19: Friction and Abrasion 265
19.1 Introduction 265
19.2 Friction 265
19.2.1 Factors Affecting Friction 265
19.2.2 Methods of Measuring Friction 268
19.2.3 Standard Methods 271
19.3 Wear 272
19.3.1 General 272
19.3.2 Wear Mechanisms 273
19.3.3 Types of Abrasion Test 274
19.3.4 Abradants 276
19.3.5 Test Conditions 276
19.3.6 Expression of Results and Standard Rubbers 278
19.3.7 Test Apparatus 279
19.3.8 Comparison of Methods 284
References 285
Chapter 20: Fatigue 288
20.1 Introduction 288
20.2 Flex-Cracking and Cut-Growth Tests 289
20.2.1 General 289
20.2.2 Flexing Methods 289
20.2.3 Tests in Tension 292
20.2.4 Tests in Shear 295
20.2.5 Other Tests 296
20.3 Heat Build-Up 297
References 299
Chapter 21: Effect of Temperature 301
21.1 Introduction 301
21.2 Thermal Expansion 302
21.3 Transition Temperature 303
21.4 Low Temperature Tests 304
21.4.1 General 304
21.4.2 Recovery Tests 305
21.4.3 Change in Stiffness 307
21.4.4 Brittleness Temperature 309
21.4.5 Comparison of Methods 311
21.4.6 Crystallisation 312
21.5 Heat Ageing 313
21.5.1 General 313
21.5.2 Standard Exposure Tests 314
21.5.3 Monitoring Degradation 316
21.5.4 Stress Relaxation 317
21.5.5 Correlation with Natural Ageing 319
References 325
Chapter 22: Effect of Environment 328
22.1 Introduction 328
22.2 Moist Heat and Steam Tests 328
22.3 Effect of Liquids 329
22.3.1 General 329
22.3.2 Standard Methods 330
22.3.3 Standard Liquids 334
22.3.4 Non-standard Methods 335
22.3.5 Water Absorption 336
22.4 Effect of Gases (Other than Ozone) 337
22.5 Effect of Ozone 337
22.5.1 General 337
22.5.2 Ozone Cabinet 338
22.5.3 Measurement of Ozone Concentration 340
22.5.4 Test Piece 341
22.5.5 Conditioning 343
22.5.6 Test Conditions 343
22.5.7 Test Procedure 344
22.5.8 Expression of Results 345
22.5.9 Dynamic Ozone Results 347
22.5.10 Stress Relaxation 347
22.6 Weathering 348
22.7 Biological Attack 351
22.8 Fire 352
22.9 Radiation 353
References 354
Part VII: Interaction with Other Materials 358
Chapter 23: Adhesion 359
23.1 Introduction 359
23.2 Adhesion to Metals 359
23.2.1 General 359
23.2.2 Standard Methods 361
23.2.2.1 Peel Tests 361
23.2.2.2 Tension Tests 362
23.2.2.3 Shear Tests 363
23.2.3 Other Methods 364
23.2.4 Non-destructive Tests 365
23.3 Adhesion to Fabrics 366
23.3.1 General 366
23.3.2 Peel Tests 366
23.3.3 Direct Tension Tests 368
23.3.4 Dynamic Tests 369
23.4 Adhesion to Cord 369
References 371
Chapter 24: Corrosion and Staining 373
24.1 Corrosion of and Adhesion to Metals 373
24.2 Staining 374
24.2.1 General 374
24.2.2 Definitions 374
24.2.3 ISO Procedure 375
24.2.4 Assessment of Staining 376
24.2.5 Other Standards 376
References 376
Index 377