Patent ID: 6858699

Claim:
A polyurethane elastomer having a node density of from 0.1 mole/kg to 0.0001 mole/kg comprising the reaction product of a) at least one polyetherester polyol having a number average molecular weight of from 1000 g/mol to 6000 g/mol, a number average functionality of from 1.9 to 2.5 and a ratio of ether groups to ester groups of from 0.3 to 2.5, which comprises a polycondensation product of a1) at least one dicarboxylic acid having up to 12 carbon atoms and/or a derivative thereof, a2) at least one polyether polyol having a number average molecular weight of from 1000 g/mol to 6000 g/mol, an average functionality of from 1.7 to 2.5 and from 70% to 100% primary OH groups, and a3) at least one polyol having a number average molecular weight of from 18 to 750 g/mol, a number average functionality of from 2 to 8 and at least 2 terminal OH groups per molecule, b) optionally, a polymer polyol having an OH number of from 10 to 149 and average functionality of from 1.7 to 4 and which comprises from 1 to 50 wt. % filler, in relation to the polymer polyol, c) a low molecular weight chain extender having an average functionality of from 1.8 to 2.1 and a number average molecular weight of from 18 to 750 g/mol and/or a cross-linking agent having an average functionality of from 2.2 to 8 and a number average molecular weight of from 18 to 750 g/mol, in the presence of d) optionally, a catalyst, e) optionally, a blowing agent and f) optionally, an additive, with g) a polyisocyanate comprising g1) an organic polyisocyanate, g2) a modified polyisocyanate, g3) an isocyanate-terminated prepolymer based on g1) and/or g2) and a polyol x), wherein the polyol x) comprises x1) a polyester polyol, x2) a polyetherester polyol or x3) a mixture of x1) and x2), g4) or a mixture of g1), g2) and/or g3).