| 摘要 |
A thermosetting composition in which high vinyl diolefin polymer chosen from among homopolymers of 1,3-butadiene and copolymers of 1,3-butadiene with styrene are admixed with about 15 to about 35 weight percent of the total polymer phase of a normally solid, elastomeric 1,3-butadiene homopolymer having high vinyl and low vinyl segments in a weight ratio of about 60:40 to about 40:60. Preferably the thermosetting composition also contains from about 15 to about 35 weight percent of the total polymeric phase of a normally solid rubbery polymer of isobutylene. A method for improving the impact strength of cured polymeric compositions in which high vinyl diolefin polymers selected from homopolymers of 1,3-butadiene and copolymers of 1,3-butadiene and styrene are admixed with about 15 to about 35 weight percent of the total polymer phase of a normally solid, elastomeric 1,3-butadiene homopolymer having high vinyl and low vinyl segments in a weight ratio of about 60:40 to about 40:60, and a curing agent, and then subjecting the composition to curing conditions. Preferably the method the composition also has admixed therein from about 15 to about 35 weight percent of the total polymeric phase of a normally solid rubbery polymer of isobutylene. The cured composition produced by the method above.
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