Abstract: Random propylene thermoplastic copolymers can be used to increase the elongation to break and toughness of thermoplastic vulcanizates. Semi-crystalline polypropylene is a preferred thermoplastic phase. The rubber can be olefinic rubbers. Random thermoplastic polypropylene copolymers are different from conventional Ziegler-Natta propylene copolymers as the compositional heterogeneity of the copolymer is greater with Ziegler-Natta copolymers. This difference results in substantial differences in properties (elongation to break and toughness) between thermoplastic vulcanizates modified with random thermoplastic propylene copolymers and those modified with conventional Ziegler-Natta propylene copolymers. An increase in elongation to break results in greater extensibility in the articles made from a thermoplastic vulcanizate.
Type:
Grant
Filed:
July 1, 1998
Date of Patent:
September 11, 2001
Assignees:
Advanced Elastomer Systems, L.P., Exxon Chemical Patents, Inc.
Inventors:
Terry Finerman, Maria D. Ellul, Sabet Abdou-Sabet, Sudhin Datta, Avi Gadkari