Thermoplastic elastomer compositions rheology-modified using peroxides and free radical coagents

This invention relates generally to rheology-modified thermoplastic elastomer (TPE) compositions that comprise an elastomeric ethylene/alpha ( )-olefin (EAO) polymer or EAO polymer blend and a high melting propylene polymer, wherein both components are peroxide-modified and to the preparation of the compositions, use of such compositions in processes such as calendaring and thermoforming to make articles of manufacture and the resulting articles of manufacture. This invention particularly relates to such compositions wherein the rheology modification is induced by a combination comprising an organic peroxide and a free radical coagent, methods for preparing the compositions, such as by modifying a physical blend of the components, and use of such compositions in calendaring operations and thermoforming applications. Rheology-modified thermoplastic elastomer compositions comprising a melt blend of an ethylene/ -olefin polymer and a high melting polymer such as polypropylene or a propylene/ -olefin copolymer wherein the rheology modification is induced by a combination of a peroxide and a free radical coagent. The resulting compositions have an elastomeric phase, a non-elastomeric phase and certain physical properties that exceed those of a like composition that is rheology-modified by peroxide alone. The compositions can be used to make a variety of articles of manufacture, such as automotive instrument panel skins, via calendaring and thermoforming procedures.