摘要 |
A process for the production of polyurethane foams by reacting a reaction mixture consisting essentially of a) a polyisocyanate component, with b) a polyol component free from salt groups, in the presence of c) at least one blowing agent, d) salts of ester-functional alpha , beta -unsaturated carboxylic acids and, optionally, e) other auxiliaries and additives typically used in polyurethane chemistry. Component d) the salts of ester-functional alpha , beta -unsaturated carboxylic acids are the reaction products of (i) monohydric or polyhydric alcohols, with (ii) unsaturated dicarboxylic acids or unsaturated dicarboxylic anhydrides, which contain on a statistical average at least one alkali metal carboxylate group and at most 0.5 alcoholic hydroxyl groups per molecule. The present invention also relates to the composites produced by back-foaming of a plastic film as a surface layer wherein the foam is produced by the process described above.
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