Polyisocyanate-polyaddition products useful for preparation of hydrolysis resistant polyurethane foam are prepared in the presence of acid anhydrides which stabilize the polyurethanes against cleavage

摘要

Polyisocyanate-polyaddition products are prepared by reaction of an isocyanate (i) with compounds reactive to isocyanates in the presence of catalysts, propellants, additives and/or adjuvants and (ii) at least one organic or inorganic acid anhydride. Independent claims are included for: (1) A mixture containing (i) an isocyanate, and (ii) at least one organic and/or inorganic acid anhydride; (2) A polyisocyanate-polyaddition product obtainable as above.