The composition of a thermoplastic elastomer obtained by a mixture of a copolymer ethylenically of very low density with a rubber based on a copolymer ethylene - to - olefin

摘要

This invention provides a thermoplastic elastomer composition obtained by blending (A) a hard segment comprising a low-density ethylene- alpha -olefin copolymer formed by copolymerizing ethylene with an alpha -olefin by the use of a specific catalyst and characterized by specifically defined properties and (B) a soft segment comprising an ethylene- alpha -olefin copolymer rubber, or obtained by partial cross-linking of the resulting blend. This elastomer composition has characteristic features such as high flexibility, good fluidity, excellent tensile properties, good thermal resistance and oil resistance and low permanent strain.