Patent ID: 7338994

Claim:
A rheology-modified, gel-free thermoplastic elastomer composition comprising from 60 to 90 weight percent, based on the weight of the composition, of at least one elastomeric ethylene/alpha-olefin polymer or ethylene/alpha-olefin polymer blend, and from 10 to 40 weight percent, based on the weight of the composition, of at least one high melting polymer selected from the group consisting of polypropylene homopolymers and propylene/ethylene copolymers, and wherein the rheology modification is induced by a combination comprising 0.075 weight percent or less peroxide, and a free radical coagent, and wherein the peroxide:coagent ratio is from 1:4 to 1:20, and the rheology-modified, gel-free thermoplastic elastomer composition has an STI of 15-30, a tan delta at 190° C. of 1.05-1.40, and a gel content that is below detectable limits when using xylene as the solvent in ASTM D 2765-90, method B; and wherein the amount of peroxide is based on the weight of the high melting polymer and the weight of either the elastomeric polymer of the elastomeric polymer blend.