| abstract |
Polyurethane-urea elastomers with improved temperature characteristics, in particular improved low temperature properties, good mechanical properties over a large temperature range and excellent resistance to hydrolysis, are obtained by reacting (A) a prepolymer, possessing cycloaliphatic NCO groups, which has been prepared from essentially difunctional polyhydroxy compounds and organic diisocyanates possessing at least one NCO group bonded to a cycloaliphatic structure, these reactants being used so as to give a ratio of total hydroxyl: NCO groups of from 1:1.2 to 1:10, with (B) 3,3',5,5'-tetramethyl-4,4'-diamino-diphenylmethane, A and B being reacted in the molar ratio of from 1:0.8 to 1:1.2. |