Abstract:
The present invention relates to foam compositions which are expanded with hydrohalocarbon blowing agents in the presence of additives which decrease the formation of haloalkenes during the polymerization. Thus, the present invention provides compositions comprising polyisocyanate, polyol, hydrohalocarbon blowing agent, catalyst, surfactant, and at least one additive wherein the additive is capable of decreasing the amount of decomposition of said dehydrohalocarbon blowing agent to haloalkenes during polymerization of the polyisocyanate and the polyol. Depending upon the polyol and polyisocyanate used and the quantity of polyisocyanate used, the compositions may be used in pour-in-place molded foams; rigid urethane spray foams; rigid high and low density foams for slabstock, froth foams, and molded foams; rigid laminated boardstock; or specialty foams.