Stritzke Custom Molding of Thermoset Elastomers

A Comprehensive Approach to Materials, Mold Design, and Processing
1. Auflage 2012
ISBN: 978-3-446-43345-8
Verlag: Hanser, Carl
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 202 Seiten

The book covers chemistry of thermoset elastomers, but only to the extent needed for understanding how to process them through a manufacturing environment and how they react in various manufacturing methods. The focus of the book is to provide in-depth coverage of tooling, processing, and secondary operations that can improve manufacturing efficiencies. Detailed and easy to understand diagrams display specific conditions and how they can be improved upon. Innovative ideas and solutions are shared and discussed.
1. Introduction to Rubber Chemistry
2. Compounding, Mixing and Equipment
3. Materials
4. Product Design
5. Material Testing for Rubber
6. Polymer Flow
7. Molding Methods
8. Compression Molding
9. Transfer Molding
10. Injection Molding
11. LSR
12. Secondary Operations and Additional Methods
13. Rubber Molding Processing

Autoren/Hrsg.

Stritzke, Bernie

Inhaltsverzeichnis

1;Acknowledgment;6
2;Preface;8
3;Contents;10
4;1 Introduction to Thermoset Elastomer Chemistry;16
4.1;1.1 Chemistry Overview;16
4.2;1.2 Polymerization;18
4.3;1.3 Thermoplastic Polymers;19
4.4;1.4 Thermoset Polymers;20
4.5;1.5 Organic and Silicone Elastomers;20
4.6;1.6 Cure Rates;22
4.7;1.7 Conclusion;22
4.8;References;22
5;2 Compounding, Mixing and Equipment;24
5.1;2.1 Introduction;24
5.2;2.2 Compounding;24
5.3;2.3 Mixing;25
5.3.1;2.3.1 TSE Compound Batch Release Tests;29
5.4;2.4 Silicone;29
5.5;2.5 Conclusion;30
5.6;References;30
6;3 Materials;32
6.1;3.1 Natural Rubber (NR);32
6.2;3.2 Synthetic Polyisoprene (IR) [2];33
6.3;3.3 Styrene-Butadiene (SBR) [3];33
6.4;3.4 Polybutadiene (BR) [4];34
6.5;3.5 Butyl (IIR) [5];34
6.6;3.6 Ethylene-Propylene-Diene (EPDM);35
6.7;3.7 Nitrile (NBR) [7];35
6.8;3.8 Polyacrylic (ACM);36
6.9;3.9 Ethylene Acrylic (AEM);36
6.10;3.10 Silicone (MQ, VMQ, and PMQ);36
6.11;3.11 Fluoroelastomer (FKM) [14];37
6.12;3.12 Polyurethane (AU and EU) [15];38
6.13;3.13 Epichlorohydrin (CO and ECO);38
6.14;3.14 Conclusion;38
6.15;References;38
7;4 Product Design;40
7.1;4.1 Introduction;40
7.2;4.2 Material;40
7.2.1;4.2.1 ASTM Classification System for Elastomeric Materials;42
7.3;4.3 Design;43
7.3.1;4.3.1 Tolerances;45
7.3.2;4.3.2 Material Shrinkage;47
7.4;4.4 Conclusion;48
7.5;References;48
8;5 Material Testing for TSE;50
8.1;5.1 Introduction;50
8.2;5.2 Physical and Chemical Properties Tests;50
8.2.1;5.2.1 Tensile Testing;51
8.2.2;5.2.2 Compression Set;52
8.2.3;5.2.3 Durometer;52
8.3;5.3 Heat Aging;53
8.3.1;5.3.1 Accelerated Aging;53
8.4;5.4 Rubber Property – Vulcanization Using Oscillating Disk Cure;53
8.5;5.5 Fluid Resistance;54
8.6;5.6 State-of-Cure;55
8.7;5.7 Conclusion;56
9;6 Polymer Flow;58
9.1;6.1 Viscosity;58
9.2;6.2 Elasticity [5];59
9.3;6.3 Plasticity [6];60
9.4;6.4 Rheology;60
9.4.1;6.4.1 Thermoplastic Fluid Properties;61
9.4.2;6.4.2 TSE Fluid Properties;63
9.5;6.5 Shear Thinning;64
9.6;6.6 Rotational Viscometers;65
9.7;6.7 Oscillating Rheometers;67
9.8;6.8 Conclusion;68
9.9;References;68
10;7 Molding Methods and Related Topics;70
10.1;7.1 Introduction;70
10.2;7.2 Choosing a Process;70
10.3;7.3 Book Mold;73
10.4;7.4 Bolt-In;74
10.5;7.5 Shuttling;74
10.5.1;7.5.1 Double Shuttle;74
10.5.2;7.5.2 Single Plate Shuttle;76
10.6;7.6 Rotary Molding;77
10.7;7.7 Core Bar;80
10.8;7.8 Mold Construction;81
10.8.1;7.8.1 Cavitation;82
10.9;7.9 Article Removal/Ejection;83
10.10;7.10 Mold Cavity Finish;83
10.11;7.11 Heaters;84
10.11.1;7.11.1 Heater Calculation [4];85
10.11.2;7.11.2 Running;87
10.11.3;7.11.3 Conclusion;87
10.12;7.12 Heat Transfer;87
10.13;7.13 Insulation;89
10.14;7.14 Vacuum;89
10.15;7.15 Release Aids;93
10.15.1;7.15.1 Mold Lubes;93
10.15.2;7.15.2 Mold Plating;93
10.16;7.16 Mold Cleaning;95
10.16.1;7.16.1 Plastic Media Blast;95
10.16.2;7.16.2 Ultrasonic Cleaners;96
10.16.3;7.16.3 Ice Blast;96
10.17;7.17 Conclusion;96
10.18;References;97
11;8 Compression Molding;98
11.1;8.1 Compression Presses;98
11.2;8.2 Preps;99
11.3;8.3 Operator Influence and Automation;100
11.4;8.4 Material Flow;101
11.4.1;8.4.1 Trapped Air;102
11.4.2;8.4.2 Molecular Orientation;102
11.5;8.5 Mold Construction;102
11.5.1;8.5.1 Disk Springs;103
11.5.2;8.5.2 Relative Cost;104
11.6;8.6 Pressure;104
11.7;8.7 Backrind;105
11.8;8.8 Mold Cleaning;105
11.9;8.9 Article Removal/Ejection;105
11.10;8.10 Compression Mold and Die-Cut;106
11.11;8.11 Dual Acting Spring Mechanism Compression Molding;107
11.11.1;8.11.1 Prep Compensating Mechanism;110
11.11.2;8.11.2 Secondary Trim;111
11.12;8.12 Conclusion;112
11.13;References;113
12;9 Transfer Molding;114
12.1;9.1 Self-Contained Pot;114
12.2;9.2 Bottomless Pot Transfer;115
12.3;9.3 Transfer Press;117
12.4;9.4 Flashless Transfer Molding;118
12.4.1;9.4.1 Split-Top Inserts;120
12.4.2;9.4.2 Vents;121
12.4.3;9.4.3 Trapped Air;122
12.4.4;9.4.4 Sprues/Gates;122
12.4.5;9.4.5 Knit Lines;123
12.4.6;9.4.6 Ring Gates;124
12.4.7;9.4.7 Mold Construction;124
12.4.8;9.4.8 Transfer Pressure;124
12.5;9.5 Mold Cleaning;125
12.6;9.6 Wasteless Transfer;126
12.6.1;9.6.1 Equalizing Platen;128
12.7;9.7 Conclusion;128
12.8;References;129
13;10 Injection Molding;130
13.1;10.1 Injection Unit;131
13.1.1;10.1.1 First In – First Out (FIFO);133
13.1.2;10.1.2 Plunger Unit;134
13.1.3;10.1.3 Injection Controls;134
13.1.4;10.1.4 Injection Location;135
13.1.5;10.1.5 Material Feed – Stripped;136
13.1.6;10.1.6 Material Feed – Stuffer;136
13.2;10.2 Materials;136
13.3;10.3 Automation;136
13.4;10.4 Mold Construction;139
13.5;10.5 Molding Defects;139
13.5.1;10.5.1 Scorch;139
13.5.2;10.5.2 Cured Stock;140
13.5.3;10.5.3 Adhesive Wash;140
13.6;10.6 Injection Transfer;140
13.7;10.7 Injection Compression;140
13.8;10.8 Cold Runner Injection;141
13.9;10.9 Valve-Gated Cold Runner;142
13.10;10.10 Injection Pressure Considerations;143
13.10.1;10.10.1 Pressure Compensator;144
13.11;10.11 Conclusion;145
13.12;References;145
14;11 Liquid Silicone Rubber;146
14.1;11.1 The System;147
14.2;11.2 The Static Mixer;147
14.3;11.3 Injection Unit;148
14.4;11.4 Molds;150
14.5;11.5 Materials;151
14.6;11.6 Special Applications;152
14.6.1;11.6.1 Medical;152
14.6.2;11.6.2 Food Contact;152
14.7;11.7 Color Or Other Additives;152
14.8;11.8 Material Change;152
14.9;11.9 Similarity to Plastic Injection Molding;153
14.10;11.10 Two-Shot Molding;153
14.11;11.11 Conclusion;156
14.12;References;156
15;12 Secondary Operations and Additional Methods;158
15.1;12.1 Post Curing;158
15.2;12.2 Material Filtering;158
15.3;12.3 Flash;159
15.3.1;12.3.1 Cryogenic Deflash;160
15.4;12.4 Coatings;161
15.4.1;12.4.1 Parylene Coating;161
15.4.2;12.4.2 Plasma Treatment;162
15.4.3;12.4.3 Chlorination;165
15.4.4;12.4.4 Oils;165
15.5;12.5 Adhesion;166
15.5.1;12.5.1 Dipping;166
15.5.2;12.5.2 Tumble Baskets;167
15.5.3;12.5.3 Chain-On-Edge;169
15.5.4;12.5.4 Rotary Table;170
15.5.5;12.5.5 Other Application Methods;171
15.5.6;12.5.6 Self-Bonding Methods;171
15.5.7;12.5.7 Substrate Preparation;172
15.6;12.6 Conclusion;173
15.7;References;173
16;13 TSE Molding Processing;176
16.1;13.1 Prototype;176
16.1.1;13.1.1 Prototype Plan;178
16.2;13.2 Production;178
16.2.1;13.2.1 Cure Time/Temperature;178
16.2.2;13.2.2 Sampling Phase;180
16.2.3;13.2.3 Qualification Phase;180
16.2.4;13.2.4 Measurement Qualification;181
16.2.5;13.2.5 Continuous Improvement Phase;183
16.3;13.3 Troubleshooting;184
16.4;13.4 Conclusion;188
16.5;References;189
17;14 Manufacturing Process Planning;190
18;Appendix 1: TSE Common Terms and Definitions;194
19;Subject Index;198

Leseproben

1. Introduction to Rubber Chemistry2. Compounding, Mixing and Equipment3. Materials4. Product Design5. Material Testing for Rubber6. Polymer Flow7. Molding Methods8. Compression Molding9. Transfer Molding10. Injection Molding11. LSR12. Secondary Operations and Additional Methods13. Rubber Molding Processing