Amine catalyst for improving the stability of polyurethane systems having halogen containing blowing agents

Catalyst compositions useful in the production of insulating polyurethane or polyisocyanurate foam are disclosed. The catalyst compositions impart increased stability of a mixture of the catalyst, a halogen-containing blowing agent, and a polyol. These catalyst compositions comprise of at least 10% of a tetraalkylguanidine and at least 10% of a tertiary amine catalyst with an isocyanate reactive group. These improved catalysts can be used with any halogenated blowing agent, and provide substantial stability benefits with the use of hydrofluoroolefins and hydrofluorochloroolefins. In an exemplary embodiment, a process includes providing a pre-mix comprising a hydrohaloolefin blowing agent, at least one polyol, water, and a catalyst comprising 10-50% tetramethylguanidine and 10-90% of one or more of an amine catalyst containing an isocyanate reactive group.