Abstract Process Economics Program Report No. 175C THERMOPLASTIC ELASTOMER BLENDS (October 1993) Thermoplastic elastomers are polymers that combine the flexibility and impact resistance of thermoset rubbers with the strength and convenient processibility of thermoplastics. This unique combination of properties is a result of the two-phase morphology of these materials. One means of preparing thermoplastic elastomers is to blend a thermoplastic with an elastomer. In this report SRI examines the technology of thermoplastic/elastomer blends, particularly blends derived from polypropylene, polyvinyl chloride, or thermoplastic polyurethane. This report contains an evaluation of a process known as dynamic vulcanization, which is one method of preparing thermoplastic elastomers with a preferred two-phase morphology. We also compare the economics for preparing thermoplastic polyolefin elastomers (TPOs) using dynamic vulcanization with the economics for preparing TPOs by the new in-reactor polymerization process. For those in the thermoplastic elastomers business, this report will be useful for its extensive review of recently published literature and the comparative economics. Users of thermoplastic elastomers will also find it useful for understanding the underlying principles of the product technology. We summarize and evaluate over 200 pertinent patents. PEP’92 GMB CONTENTS GLOSSARY xiii 1 INTRODUCTION 1-1 2 SUMMARY 2-1 GENERAL ASPECTS OF TPE BLENDS 2-1 Polypropylene Blends 2-1 Polyvinyl Chloride Compounds and Blends 2-2 Thermoplastic Polyurethane Blends 2-2 TECHNICAL ASPECTS 2-2 Dynamic Vulcanization 2-3 Extrusion Compounding 2-3 ECONOMIC ASPECTS 2-3 3 INDUSTRY STATUS 3-1 OVERVIEW 3-1 THERMOPLASTIC POLYOLEFIN ELASTOMERS 3-2 Producers of Thermoplastic Polyolefin Elastomers 3-3 Markets for Thermoplastic Olefin Elastomers 3-3 POLYVINYL CHLORIDE COMPOUNDS AND BLENDS 3-6 THERMOPLASTIC POLYURETHANE BLENDS 3-7 4 TYPES OF POLYMER BLENDS 4-1 MISCIBLE BLENDS 4-3 TWO-PHASE BLENDS 4-3 COMPATIBILIZERS 4-4 5 POLYPROPYLENE BLENDS 5-1 REVIEW OF POLYPROPYLENE BLENDS 5-3 Polypropylene/EP(D)M 5-3 Polypropylene/EPDM Vulcanizates 5-8 Polypropylene/Nitrile Rubber 5-16 Polypropylene/Butyl Rubber 5-20 Polypropylene Blends WIth Other Elastomers 5-22 - iii - CONTENTS (Continued) 5 POLYPROPYLENE BLENDS (Concluded) BLENDING EQUIPMENT AND PROCEDURES 5-23 COMMERCIAL VULCANIZATION 5-24 PROCESS DESCRIPTION 5-25 CAPITAL INVESTMENT 5-29 CONVERSION COSTS 5-29 PRODUCTION COSTS 5-29 6 POLYVINYL CHLORIDE BLENDS 6-1 REVIEW OF POLYVINYL CHLORIDE BLENDS 6-2 Polyvinyl Chloride/Nitrile Rubber 6-2 Polyvinyl Chloride/Polyurethane 6-5 Polyvinyl Chloride/Ethylene-Vinyl Acetate 6-6 Polyvinyl Chloride/Chlorinated Polyethylene 6-7 Other Polyvinyl Chloride Blends 6-8 BLENDING EQUIPMENT AND PROCEDURES 6-8 COMMERCIAL VULCANIZATION 6-9 PROCESS DESCRIPTION 6-10 CAPITAL INVESTMENT 6-14 CONVERSION COSTS 6-14 PRODUCTION COSTS 6-14 7 THERMOPLASTIC POLYURETHANE BLENDS 7-1 REVIEW OF POLYURETHANE BLENDS 7-1 TPU/ABS 7-2 TPU/Polycarbonate 7-6 Other Polyurethane Blends 7-7 PROCESS DESCRIPTION 7-7 PRODUCTION COSTS 7-8 - iv - CONTENTS (Concluded) APPENDIX A: PATENT SUMMARY TABLES A-1 APPENDIX B: DESIGN AND COST BASES B-1 APPENDIX C: PRODUCT INFORMATION C-1 APPENDIX D: EQUIPMENT SUPPLIERS D-1 APPENDIX E: CITED REFERENCES E-1 APPENDIX F: PATENT REFERENCES BY COMPANY F-1 - v - - vi - ILLUSTRATIONS 4.1 Typical Stress-Strain Curves 4-2 5.1 Structures of Homopolymer Polypropylene 5-1 5.2 Yield Stress and E Modulus Versus PP Content of Blends Consisting of Homopolymer PP (MFR 10) and HMW Semicrystalline EPDM 5-5 5.3 Elastic Recovery Versus PP Content of Blends Consisting of Homopolymer PP (MFR 10) and HMW Semicrystalline EPDM 5-6 5.4 Effect of Thermoplastic Fraction (fH) on Modulus of EPDM/PP Elastomeric Blends 5-11 5.5 Effect of Polypropylene Content on Tensile Strength 5-12 5.6 Effect of Crosslink Density on Tensile Strength and Tension Set 5-13 5.7 Effect of Vulcanized Elastomer Particle Size on Mechanical Properties 5-14 5.8 Effect of Curative Level on Polypropylene/Nitrile Rubber Physical Properties 5-19 5.9 Polypropylene Blends by Dynamic Vulcanization 5-28 6.1 Polyvinyl Chloride Blends by Dynamic Vulcanization 6-13 7.1 Izod Impact Strength of Heat Resistant Grade ABS/Polyester TPU System 7-3 7.2 TPU/ABS Blends Tensile Strength and 100% Modulus Versus ABS Content 7-4 7.3 Line For Blending of Polyolefin Thermoplastics 7-9 - vii - - viii - TABLES 2.1 Thermoplastic Polyolefin Elastomers Manufacturing Cost Summary 2-5 2.2 Thermoplastic PVC and TPU Blends Manufacturing Cost Summary 2-6 3.1 Thermoplastic Elastomers 1991 Consumption 3-2 3.3 Consumption of TPOs in 1991 3-5 3.4 1991 Consumption of TPOs by End-use 3-5 3.2 Producers of Thermoplastic Olefin Elastomers 3-9 3.5 Producers of PVC Compounds and Blends 3-11 5.1 Polypropylene Blends Patent Summary A-3 5.2 Property Comparison of DexflexÔ with Dexter Corp. Patent Example 5-7 5.3 Curing Systems 5-9 5.4 Property Comparison of Santoprene® with Monsanto Patent Example 5-15 5.5 Block Copolymers For NBR/PP Compatibilization 5-18 5.6 Property Comparison of Geolast® with Monsanto Patent Example 5-20 5.7 Property Comparison of TrefsinÔ with Tonen Sekiyukagaku/Exxon Chemical Patent Example 5-22 5.8 Polypropylene Blends Major Equipment 5-26 5.9 Polypropylene Blends Utilities Summary 5-27 5.10 Polypropylene Blends Total Capital Investment 5-30 5.11 Polypropylene Blends Thermoplastic/Elastomer Vulcanizates Dynamic Vulcanization Conversion Costs 5-31 5.12 Polypropylene Blends Product Value of PP/EPDM Vulcanized Blend 5-32 - ix - TABLES (Continued) 5.13 Polypropylene Blends Product Value of PP/NBR Vulcanized Blend 5-33 5.14 Polypropylene Blends Product Value of PP/Bromobutyl Rubber/ EPDM Vulcanized Blend 5-34 5.15 Reactor Thermoplastic Polyolefin Production Costs 5-35 6.1 Polyvinyl Chloride Blends Patent Summary A-26 6.2 Commercial PVC/NBR Blends 6-3 6.3 Polyvinyl Chloride Blends Major Equipment 6-11 6.4 Polyvinyl Chloride Blends Utilities Summary 6-12 6.5 Polyvinyl Chloride Blends Total Capital Investment 6-15 6.6 Polyvinyl Chloride Blends Thermoplastic/Elastomer Vulcanizates Conversion Costs 6-16 6.7 Polyvinyl Chloride Blends Product Value of PVC/NBR Blend 6-17 7.1 Polyurethane Blends Patent Summary A-43 7.2 Property Comparison of PrevailÔ with Dow Patent Example 7-5 7.3 Property Comparison of Texin® with Mobay Patent Example 7-7 7.4 Thermoplastic Polyurethane Blends Product Value of TPU/ABS Blend 7-10 7.5 Thermoplastic Polyurethane Blends Product Value of TPU/Polycarbonate Blend 7-11 C.1 PP/EP Blend DexflexÔ Product Information Injection Molding Grades C-3 - x - TABLES (Concluded) C.2 PP/EP Blend VistaFlexÔ Product Information C-4 C.3 PP/EP Blend Polytrope® Product Information C-5 C.4 PP/EPDM Vulcanizate Santoprene® Product Information C-12 C.5 PP/NBR Vulcanizate Geolast® Product Information C-18 C.6 PP/Elastomer Vulcanizate Sarlink® Product Information C-19 C.7 PVC/NBR Blend Bur-A-Loy® Product Information C-20 C.8 PVC/NBR Blend Krynac Nv870 Product Information C-28 C.9 PVC/NBR Blends Paracril Ozo® Product Information C-31 C.10 PVC/NBR Blends Nipol® Product Information C-32 C.11 PVC/TPU Blends 90-P513A Product Information C-33 C.12 TPU/ABS Blends PrevailÔ Product Information C-34 - xi -.