POLYURETHANE FOAM PREMIXES CONTAINING HALOGENATED OLEFIN BLOWING AGENTS AND FOAMS MADE FROM SAME

摘要

The invention provides polyurethane and polyisocyanurate foams and methods for the preparation thereof. More particularly, the invention relates to closed-celled, polyurethane and polyisocyanurate foams and methods for their preparation. The foams are characterized by a fine uniform cell structure and little or no foam collapse. The foams are produced with a polyol premix composition which comprises a combination of a hydrohaloolefin blowing agent, a polyol, a silicone surfactant, and a precipitation-resistant metal-based catalyst used alone or in combination with an amine catalyst.