| 摘要 |
1,258,992. Polyurethanes. FARBENFABRIKEN BAYER A.G. 4 Nov., 1969 [15 Nov., 1968], No. 53967/69. Heading C3R. [Also in Division C2] Diamines of the general formula in which the amino groups and chlorine atoms are in o-position to each other and in which A is a straight or branched C 2 -C 12 alkylene group or a group -BXB- in which B is a C 1 -C 6 alkylene group and X is -O-, -S-, -SO 2 -, or in which R is a C 1 -C 4 alkyl group with the proviso that if A-(CH 2 ) 5 - then the amino groups are not in the 4-position in the aromatic rings, are used as chain-lengthening agents in the production of polyurethane elastomers from compounds having at least two hydroxyl groups and a molecular weight of 800-5000 and diisocyanates. Suitable compounds with two hydroxyl groups are, for example, polyesters with terminal hydroxyl groups, polyethers with terminal hydroxy groups, addition products of alkylene oxides and polyfunctional alcohols, amino-alcohols or amines; and polyacetals, polythioethers or polycarbonates having at least two -OH groups. The diisocyanates used may be aliphatic, cycloaliphatic, araliphatic or aromatic. |
