An improved process for the preparation of thermoplastic elastomers by hydrosilylation crosslinking of a butyl rubber component, in which a platinum containing hydrosilylation catalyst is used. The butyl rubber component includes a copolymer of at least isobutylene and an aromatic divinyl compound such as divinylbenzene. The copolymer of at least isobutylene and divinylbenzene is significantly easier to crosslink into a substantially insoluble rubber in a thermoplastic vulcanizate than isobutylene copolymers with only unsaturated repeating units from conjugated dienes. A crosslinked rubber component is obtained in the thermoplastic elastomer composition.
展开▼