PREPARATION OF CAST ELASTOMERS USING AIMINOCROTONATE-TERMINATED POLYETHER CHAIN EXTENDERS

摘要

This invention relates to a process for preparing polyurethane elastomers comprising reacting in an open mold at an isocyanate index of about 90 to about 110 (a) an isocyanate prepolymer having an isocyanate content of about 2 to about 15% by weight and a molecular weight of from about 500 to about 5000 prepared by reaction of (i) at least one organic polyisocyanate with (ii) at least one isocyanate-reactive compound having at least two isocyanate-reactive groups and a molecular weight of from about 250 to about 4000; with (b) certain aminocrotonate-terminated polyethers having a molecular weight of from about 500 to about 1500; (c) optional chain extenders and/or crosslinkers other than aminocrotonate-terminated polyether (b); and (d) optional auxiliaries and/or additives.