Abstract: A radiation resistant cross linked polymer composition for maintaining appropriate physical properties after it is exposed to radiation comprising polymer components and a softening agent in an amount of 3 weight parts or more with respect to 100 weight parts of the polymer components. The polymer components comprise a first polymer component of one or more polymer selected from the group consisting of butyl rubber, polyisobutylene rubber, epichlorohydrin rubber and polypropylene in a content of 3 to 70 weight parts and a second polymer component of one or more polymer selected from the group consisting of chloroprene rubber and a polymer containing an ethylene unit as a main component in a content of 97 to 30 weight parts.

Abstract: An object of the present invention is to provide a radiation resistant polymer composition for maintaining appropriate physical properties after it is exposed to radiation. The invention provides a radiation resistant cross linked polymer composition comprising polymer components and a softening agent in an amount of 3 weight parts or more with respect to 100 weight parts of the polymer components. The polymer components comprise a first polymer component of one or more polymer selected from the group consisting of butyl rubber, polyisobutylene rubber, epichlorohydrin rubber and polypropylene in a content of 3 to 70 weight parts and a second polymer component of one or more polymer selected from the group consisting of chloroprene rubber and a polymer containing an ethylene unit as a main component in a content of 97 to 30 weight parts.