PROCESS FOR MAKING RIGID POLYURETHANE FOAMS

摘要

Process for making rigid polyurethane or urethane-modified polyisocyanurate foams at an isocyanate index of between 110 and 120 comprising the step of reacting an organic polyisocyanate composition with an isocyanate-reactive composition in the presence off a hydrocarbon as blowing agent wherein the isocyanate-reactive composition contains between 3 and 30 wt% of polyester polyols and between 20 and 50 wt% of polyether polyols derived from aromatic amines, the amounts being calculated on the basis of total isocyanate-reactive compound.