Patent ID: 6423757
Filing Date: 2002-07-23
Classification: C08J,C09K,Y10S

Abstract:
A process to produce a polyurethane foam or a polyisocyanurate foam, which processes comprises:(A) combining a mixture of compounds needed to produce a polyurethane with a sufficient quantity of the azeotrope-like mixture as a blowing agent, under reaction conditions which produce a foamed polyurethane; or (B) combining a mixture of compounds needed to produce a polyisocyanurate with a sufficient quantity of the azeotrope-like mixture as a blowing agent, under reaction conditions which produce a foamed polyisocyanurate; wherein said blowing agent is an azeotrope-like mixture, which mixture comprises: (a) pentafluoropropane; and (b) a hydrofluorocarbon of the formula: CxFyHz wherein x is 3, 4, 5, or 6 and y and z are each independently 1 or a positive whole number such that the result of y/(y+z) is greater than 0.67.