Patent ID: 6784217
Filing Date: 2004-08-31
Classification: C08G,Y10S

Abstract:
A process for preparing a high resilience flexible polyurethane foam at an NCO index of 70-120, which process is a prepolymer process, by reacting:a) a polyisocyanate composition comprising at least 80% by weight of 4,4â€²-MDI; b1) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxy functionality of 2-6, where the EO is present as tipped EO and/or random EO, the total EO content being at least 50% by weight; b2) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxy functionality of 2-6, where the EO is present as tipped EO and/or random EO, the total EO content being between 20-50% by weight, having a primary hydroxy content of at least 50%; and optionally b3) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxyl functionality of 2-6, having a primary hydroxy content of at least 50%, and having an EO content of from 10 to 20% by weight; these polyols b1, b2 and b3 being reacted according to the following proportions, based on the combined weights of b1, b2 and b3, b1: 40-90 wt %, b2: 5-60 wt %, b3: 0-20 wt %; c) water; and d) additives and auxiliaries known per se; and where a polyisocyanate prepolymer is used which has an NCO value below 20% by weight.