blowing agent free polyisocyanate prepolymer composition, method for forming a polyurethane foam, blowing agent for a polyurethane foam and blowing agent free foam.

摘要

A polyisocyanate prepolymer composition is comprised of the reaction product of (a) a polyisocyanate having an average functionality of at least 2 and containing at least about 20 percent by weight of a diisocyanate monomer, (b) a monohydric alcohol and (c) a polyol having an average hydroxyl functionality of at least about 1.8 to at most about 3.2 wherein the prepolymer composition has (i) an amount of isocyanate groups by weight sufficient to react with water in the absence of a supplemental blowing agent to make a foam, (ii) at most about 10.0 percent by weight of the diisocyanate monomer and (iii) an amount of the polyisocyanate that is capped by the monohydric alcohol sufficient to prevent gelling of the prepolymer composition. The prepolymer composition may be reacted with water to form a polyurethane foam.