Cold hardening polyurethanes

1,140,314. Polyurethanes. FARBENFABRIKEN BAYER A.G. 26 Jan., 1967 [19 Feb., 1966], No. 3922/67. Heading C3R. Cold hardening casting polyurethanes are prepared by reacting a polyether containing hydroxyl groups, a polyisocyanate and, if desired, a chain lengthening agent in the presence of a catalyst mixture comprising an organic alkali metal compound and an activated alkali metal aluminosilicate which possesses a zeolite structure. Conventional polyethers, aliphatic and aromatic polyisocyanates, diol and diamine chain lengthening agents may be used. The alkali metal compound may be sodium acetate, sodium propionate, sodium oleate, sodium phenolate, sodium nitrophenol, sodium dinitrophenol, sodium chlorophenol, sodium trichlorophenol and sodium pentaglycol. Sodium aluminosilicate of the general formula is the preferred activated alkali metal aluminosilicate. Fillers such as ground shale, quartz sand, powdered brick, kaolin, carbon black and tar may be added to the reaction mixture.