A PROCESS FOR THE PRODUCTION OF RIGID AND SEMI-RIGID FOAMS WITH LOW AMOUNTS OF DIISOCYANATE USING POLYMER POLYOLS CHARACTERIZED BY HIGH SOLIDS AND A HIGH HYDROXYL NUMBER AND THE RESULTANT FOAMS.

摘要

This invention relates to a process for the production of rigid and semi-rigid foams at low isocyanate levels, and to the foams produced by this process. The process comprises reacting a polyisocyanate component with an isocyanate-reactive component, in the presence of at least one blowing agent, at least one surfactant and at least one catalyst. Suitable isocyanate-reactive components are characterized as having a solids content of at least 40 % by weight, and an overall hydroxyl number of the remaining liquid, non-solids portion of at least 160. In addition, the isocyanate-reactive component comprises at least 50 % by weight of a polymer polyol having a solids content of at least 30 % by weight and in which the base polyol has a hydroxyl number of at least 75.