POLYOLEFIN THERMOPLASTIC VULCANIZATE ELASTOMERS

摘要

Thermoplastic vulcanizate elastomer obtained by dynamic vulcanization of a heterophasic polyolefin composition in presence of at least (i) an alkenyl-substituted alkoxysilane grafting agent and (ii) water; wherein said heterophasic polyolefin composition has flexural modulus equal to or lower than 150 MPa, and comprises: (a) a crystalline propylene homopolymer or copolymer of propylene with up to 15% of ethylene or other alpha-olefin comonomer(s), or their combinations, and (b) a copolymer or a composition of copolymers of ethylene with other alpha-olefins, containing from 15% to 40% of ethylene, said thermoplastic vulcanizate elastomer having compression set values in the range from 45-65%, the ratio of elongation at break to compression set values over 10 and hardness shore A values below 90.