Crosslinked chlorinated polyethylene foam

A process for preparing a crosslinked, soft, flexible, closed-cell foam from suspension chlorinated high density polyethylene, said process comprising

• (a) preparing a foamable mixture by mixing a high density polyethylene containing from about 20 to 50 percent of chemically combined chlorine by suspension and having a flexural modulus at 25.degree. C. of less than about 15,000 psi as determined by ASTM Test No. 790, Method 1, Procedure A, with a thermally decomposable chemical foaming agent,
• (b) melt molding said foamable mixture at a temperature below that of the decomposition temperature of said chemical foaming agent, into a molded foamable article,
• (c) subjecting said molded foamable article while maintained at a temperature below the decomposition temperature of said foaming agent to an ionizing radiation, for a period of time sufficient to impart crosslinking sufficient to enable said molded foamable article to retain its shape, and
• (d) contacting the crosslinked molded foamable article, with a heat transfer medium maintained at a temperature between about 150.degree. C. and about 350.degree. C. for a period of time sufficient to form the desired flexible product.