PROCEDURE FOR THE PRODUCTION OF RIGID AND SEMI-RIGIDED FOAMS WITH SMALL AMOUNTS OF DIISOCIANATE USING POLYMER POLYMERS CHARACTERIZED BY A HIGH CONTENT OF SOLIDS AND A HIGH INDEX OF HYDROXYL AND THE RESULTS.

摘要

A rigid or semi-rigid polyurethane foam comprising the reaction product of: (A) less than 75 pep, based on 100 pep of component (B), of at least one polyisocyanate; with (B) an isocyanate reactive component having a solids content of at least 40% by weight, an overall hydroxyl number of the liquid, non-solid portion of at least 160, and comprising: (1) at least 50% by weight of a polymer polyol having a solids content of at least 30% by weight, wherein the base polyol of the polymer polyol has a hydroxyl number of at least 70 and a functionality of 2 to 8 , and (2) not more than 50% by weight of one or more second polyols, said second polyol being different from the polymer polyol (1), with the sum of the% by weight of polyols (1) and (2) totaling the 100% by weight of (B); in the presence of (C) at least one blowing agent; (D) at least one surfactant; and (E) at least one catalyst.