CPC C08G 18/4816 (2013.01) [C08G 18/485 (2013.01); C08G 18/7621 (2013.01); C08G 2110/0083 (2021.01)] | 5 Claims |
1. A process for the production of a polyurethane foam having a resilience of at least 50% measured by ball rebound test, said process comprising (1) reacting (i) a first polyether polyol comprising polyether chains containing at least 3 wt % and no more than 20 wt % oxyethylene content, and having a primary hydroxyl content of no more than 20% and a functionality of at most 3.5 and a hydroxyl value of at least 40 mg KOH/g; (ii) a second polyether polyol comprising polyether chains containing at least 50 wt % oxyethylene content and having a hydroxyl value of at most 48 mg KOH/g; and (iii) one or more aromatic polyisocyanates, in the presence of one or more catalysts having gelling and/or blowing activities, and (2) allowing a full rise of the foam, wherein the weight ratio of the first polyether polyol to the second polyether polyol is at least 5:1, and wherein the first polyether polyol is prepared by ring-opening polymerisation of alkylene oxides onto a hydroxyl containing starting material in the presence of a composite metal cyanide complex catalyst.
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