Patent ID: 7772353

Claim:
A process for the production of a polyurethane elastomer comprising reacting a reaction mixture by a reaction injection molding technique, wherein the reaction mixture comprises: (A) a polyisocyanate component having an NCO group content of about 20 to about 45% by weight, a functionality of about 2.0 to about 2.7, and comprising a trimerized (cyclo)aliphatic polyisocyanate, with the proviso that (i) when the (cyclo)aliphatic polyisocyanate is trimerized isophorone diisocyanate, component (A) contains less than 20% by weight of trimerized hexamethylene diisocyanate, and (ii) when the (cyclo)aliphatic polyisocyanate is trimerized hexamethylene diisocyanate, component (A) contains less than 10% by weight of isophorone diisocyanate; with (B) an isocyanate-reactive component which is free of amine groups and comprising: (1) from about 70 to about 90% by weight, based on 100% by weight of (B), of one or more polyether polyols having a functionality of from about 2 to about 8, a molecular weight of about 1,000 to about 8,000 g/mol and is free of amine groups; (2) from about 10 to about 30% by weight, based on 100% by weight of (B), of one or more organic compounds having a molecular weight of from about 62 to about 400 g/mol, having a hydroxyl functionality of 2 to 3, and is free of amine groups, in the presence of (C) one or more catalysts corresponding to the formula: wherein: m: represents an integer from 3 to 8, and n: represents an integer from 3 to 8; and, optionally, (D) one or more additives; wherein the relative amounts of (A) and (B) are such that the isocyanate index ranges from about 90 to about 120.