Abstract A thermoplastic elastomer composition comprising (A) 10-90 parts by weight of crystalline polypropylene, (B) 10-90 parts by weight of brominated butyl rubber, (C) 10-120 parts by weight of olefinic copolymer rubber to 100 parts by weight of (A)+(B), and (D) 10-150 parts by weight of process oil as plasticizer to 100 parts by weight (A)+(B), all of which are dynamically vulcanized in the presence of a peroxide crosslinking agent. The thermoplastic elastomer composition of this invention has a high gel ratio or gel content in part because brominated butyl rubber is vulcanized with peroxide. The composition has good elasticity, high mechanical strength, low compressively permanent set, excellent long-term heat stability, moldability, and gas impermeability and high damping characteristic.
A thermoplastic elastomer composition comprising (A) 10-90 parts by weight of crystalline polypropylene, (B) 10-90 parts by weight of brominated butyl rubber, (C) 10-120 parts by weight of olefinic copolymer rubber to 100 parts by weight of (A)+(B), and (D) 10-150 parts by weight of process oil as plasticizer to 100 parts by weight (A)+(B), all of which are dynamically vulcanized in the presence of a peroxide crosslinking agent.
Claim 2
Dependent Claim
69 words
A thermoplastic elastomer composition comprising (A) 10-90 parts by weight of crystalline polypropylene, (B) 10-90 parts by weight of brominated butyl rubber, (C) 10-120 parts by weight of olefinic copolymer rubber to 100 parts by weight of (A)+(B), and (D) 10-150 parts by weight of process oil as plasticizer to 100 parts by weight (A)+(B), all of which are dynamically vulcanized in the presence of a peroxide crosslinking agent.
Claim 3
Dependent Claim
24 words
The thermoplastic elastomer composition of claim 1 characterized by the bromine content of the above-described brominated butyl rubber being 0.5 wt. % or more.
Claim 4
Dependent Claim
22 words
The thermoplastic elastomer composition of claim 2 characterized by the bromine content of the above-described brominated butyl rubber being 0.5-8 wt. %.
Claim 5
Dependent Claim
22 words
The thermoplastic elastomer composition of claim 3 characterized by the bromine content of the above-described brominated butyl rubber being 0.5-4 wt. %.
Claim 6
Dependent Claim
22 words
The thermoplastic elastomer of claims 1 or 2 wherein said olefinic copolymer rubber is either ethylene-propylene copolymer rubber or ethylene-propylene-diene copolymer rubber.