Extrudable elastomeric composition having controlled rate of degradation.

摘要

An extrudable elastomeric composition including an elastomeric A-B-A min block copolymer where A and A min are each a thermoplastic polymer endblock and where B is a conjugated diene monomer unit having a low degree of residual ethylenic unsaturation; a polyolefin; and an effective amount of a transition metal compound which is substantially uniformly distributed in the blend containing the polyolefin and block copolymer so that the extrudable elastomeric composition is adapted form an elastic sheet that is degraded after less than about 30 days continuous exposure to a thermally oxidative environment. The transition metal compound may be a salt or complex of cobalt and/or manganese and is added in an amount that will provide at least about 0.01 percent, by weight, of the transition metal in the extrudable composition.