PROCESS FOR MAKING RIGID POLYURETHANE FOAMS

摘要

Process for preparing rigid polyurethane or urethane-modified polyisocyanurate foam comprising the step of reacting an organic polyisocyanate composition with a polyfunctional isocyanate-reactive composition in the presence of at least one blowing agent wherein the polyfunctional isocyanate-reactive composition contains (a) from 20 to 60 wt% of an aromatic initiated polyether polyol, (b) from 20 to 60 wt% of a polyether polyol of functionality 4 or more and (c) from 0 to 40 wt% of a polyether polyol of functionality less than 4, the total amounts of polyols (a), (b) and (c) equal to 100 wt%.