Costas N. Georgacopoulos - Berlin CT
Curtis P. Smith - Cheshire CT
The Upjohn Company - Kalamazoo MI
Thermoplastic compositions are disclosed which comprise blends of about 50 to about 85 percent by weight of a thermoplastic polyurethane and the balance of the blend comprising (a) a polyvinyl halide resin and (b) a diene-nitrile copolymer rubber, the weight ratio of (a) to (b) being within the range of from about 1:4 to about 1. 5:1.
The novel blends do not melt or spread flaming drip when combusted but rather form chars. The blends are optionally fire retarded by the addition of flame retardants.
The fire retarded blends find utility in, inter alia, electric wire and cable jacketing where a high degree of fire retardance is required. The blends without fire retardants provide a good thermoplastic polyurethane at lower cost than the polyurethanes alone and find utility in those applications normally associated with polyurethanes such as films, footwear, wire jacketing, and particularly those applications calling for a higher degree of oil resistance than polyurethanes alone.