PEP’92 GMB

Abstract

Process Economics Program Report No. 175C

THERMOPLASTIC ELASTOMER BLENDS

(October 1993)

Thermoplastic elastomers are polymers that combine the flexibility and impact resistanceof thermoset rubbers with the strength and convenient processibility of thermoplastics. Thisunique 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, particularlyblends derived from polypropylene, polyvinyl chloride, or thermoplastic polyurethane.

This report contains an evaluation of a process known as dynamic vulcanization, which isone method of preparing thermoplastic elastomers with a preferred two-phase morphology. Wealso compare the economics for preparing thermoplastic polyolefin elastomers (TPOs) usingdynamic vulcanization with the economics for preparing TPOs by the new in-reactorpolymerization process.

For those in the thermoplastic elastomers business, this report will be useful for itsextensive review of recently published literature and the comparative economics. Users ofthermoplastic elastomers will also find it useful for understanding the underlying principles of theproduct technology. We summarize and evaluate over 200 pertinent patents.

- iii -

CONTENTS

GLOSSARY xiii

1 INTRODUCTION 1-1

2 SUMMARY 2-1

GENERAL ASPECTS OF TPE BLENDS 2-1Polypropylene Blends 2-1Polyvinyl Chloride Compounds and Blends 2-2Thermoplastic Polyurethane Blends 2-2

TECHNICAL ASPECTS 2-2Dynamic Vulcanization 2-3Extrusion Compounding 2-3

ECONOMIC ASPECTS 2-3

3 INDUSTRY STATUS 3-1

OVERVIEW 3-1

THERMOPLASTIC POLYOLEFIN ELASTOMERS 3-2Producers of Thermoplastic Polyolefin Elastomers 3-3Markets 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 5-3Polypropylene/EP(D)M 5-3Polypropylene/EPDM Vulcanizates 5-8Polypropylene/Nitrile Rubber 5-16Polypropylene/Butyl Rubber 5-20Polypropylene Blends WIth Other Elastomers 5-22

- iv -

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 6-2Polyvinyl Chloride/Nitrile Rubber 6-2Polyvinyl Chloride/Polyurethane 6-5Polyvinyl Chloride/Ethylene-Vinyl Acetate 6-6Polyvinyl Chloride/Chlorinated Polyethylene 6-7Other 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 7-1TPU/ABS 7-2TPU/Polycarbonate 7-6Other Polyurethane Blends 7-7

PROCESS DESCRIPTION 7-7

PRODUCTION COSTS 7-8

- v -

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

- vi -

- vii -

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 ofHomopolymer PP (MFR 10) and HMW Semicrystalline EPDM 5-5

5.3 Elastic Recovery Versus PP Content of Blends Consisting ofHomopolymer PP (MFR 10) and HMW Semicrystalline EPDM 5-6

5.4 Effect of Thermoplastic Fraction (φH) on Modulus ofEPDM/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 onPolypropylene/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 GradeABS/Polyester TPU System 7-3

7.2 TPU/ABS BlendsTensile Strength and 100% Modulus Versus ABS Content 7-4

7.3 Line For Blending of Polyolefin Thermoplastics 7-9

- viii -

- ix -

TABLES

2.1 Thermoplastic Polyolefin ElastomersManufacturing Cost Summary 2-5

2.2 Thermoplastic PVC and TPU BlendsManufacturing 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 BlendsPatent Summary A-3

5.2 Property Comparison of Dexflex 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 Trefsin withTonen Sekiyukagaku/Exxon Chemical Patent Example 5-22

5.8 Polypropylene BlendsMajor Equipment 5-26

5.9 Polypropylene BlendsUtilities Summary 5-27

5.10 Polypropylene BlendsTotal Capital Investment 5-30

5.11 Polypropylene BlendsThermoplastic/Elastomer VulcanizatesDynamic Vulcanization Conversion Costs 5-31

5.12 Polypropylene BlendsProduct Value of PP/EPDM Vulcanized Blend 5-32

- x -

TABLES (Continued)

5.13 Polypropylene BlendsProduct Value of PP/NBR Vulcanized Blend 5-33

5.14 Polypropylene BlendsProduct Value of PP/Bromobutyl Rubber/EPDM Vulcanized Blend 5-34

5.15 Reactor Thermoplastic PolyolefinProduction Costs 5-35

6.1 Polyvinyl Chloride BlendsPatent Summary A-26

6.2 Commercial PVC/NBR Blends 6-3

6.3 Polyvinyl Chloride BlendsMajor Equipment 6-11

6.4 Polyvinyl Chloride BlendsUtilities Summary 6-12

6.5 Polyvinyl Chloride BlendsTotal Capital Investment 6-15

6.6 Polyvinyl Chloride BlendsThermoplastic/Elastomer VulcanizatesConversion Costs 6-16

6.7 Polyvinyl Chloride BlendsProduct Value of PVC/NBR Blend 6-17

7.1 Polyurethane BlendsPatent Summary A-43

7.2 Property Comparison of Prevail with Dow Patent Example 7-5

7.3 Property Comparison of Texin® with Mobay Patent Example 7-7

7.4 Thermoplastic Polyurethane BlendsProduct Value of TPU/ABS Blend 7-10

7.5 Thermoplastic Polyurethane BlendsProduct Value of TPU/Polycarbonate Blend 7-11

C.1 PP/EP BlendDexflex Product InformationInjection Molding Grades C-3

- xi -

TABLES (Concluded)

C.2 PP/EP BlendVistaFlex Product Information C-4

C.3 PP/EP BlendPolytrope® Product Information C-5

C.4 PP/EPDM VulcanizateSantoprene® Product Information C-12

C.5 PP/NBR VulcanizateGeolast® Product Information C-18

C.6 PP/Elastomer VulcanizateSarlink® Product Information C-19

C.7 PVC/NBR BlendBur-A-Loy® Product Information C-20

C.8 PVC/NBR BlendKrynac Nv870 Product Information C-28

C.9 PVC/NBR BlendsParacril Ozo® Product Information C-31

C.10 PVC/NBR BlendsNipol® Product Information C-32

C.11 PVC/TPU Blends90-P513A Product Information C-33

C.12 TPU/ABS BlendsPrevail Product Information C-34