Abstract: Disclosed are several methods of parting rubber from an underlying surface. Polyvinyl alcohol, methylcellulose, starch derivatives and dextran are allsuitable parting agents for rubber. Polyvinyl pyrrolidine is a particularly effective parting agent for use in the formation of balloon-type medical catheters; it is also useful as a parting agent in the formation of synthetic membranes, blood vessels andconduits. The invention includes the method of use of these parting agents as well as the products formed by the disclosed process(es). Also disclosed is a method of forming a synthetic blood vessel of a polymer material, e.g., polyurethane.