Abstract: A microcellular polyurethane or polyurethane-urea foam elastomer includes the reaction product of (A) with (B) and/or water, a blowing agent, a catalyst forming urethane and/or ureic groups wherein: (A) is a prepolymer having a —NCO free group content included between 2%-25% (% w/w), which includes the reaction product of (a1) one or more aliphatic, cycloaliphatic and/or aromatic diisocyanates excluding 3,3?-dimethyl-4,4?-diphenylene diisocyanate, or one or more polyisocyanates or mixture of diisocyanates and polyisocyanates; with (a2a) one or more polyester macrodiols, a number of —OH groups per molecule equal to about 2; (B) is a compound selected from (b1) a diol or polyol; (b2) a primary or secondary aliphatic, cycloaliphatic amine or aliphatic, cycloaliphatic aromatic disecondary diamine or a blocked amine; (b3) one or more polyester macrodiols having a number of —OH group per molecule equal to about 2; (b4) a mixture formed of two or more compounds (b1), (b2) and (b3).

Abstract: A microcellular polyurethane or polyurethane-urea foam elastomer includes the reaction product of (A) with (B) and/or water, a blowing agent, a catalyst forming urethane and/or ureic groups wherein: (A) is a prepolymer having a —NCO free group content included between 2%-25% (% w/w), which includes the reaction product of (a1) one or more aliphatic, cycloaliphatic and/or aromatic diisocyanates excluding 3,3?-dimethyl-4,4?-diphenylene diisocyanate, or one or more polyisocyanates or mixture of diisocyanates and polyisocyanates; with (a2a) one or more polyester macrodiols, a number of —OH groups per molecule equal to about 2; (B) is a compound selected from (b1) a diol or polyol; (b2) a primary or secondary aliphatic, cycloaliphatic amine or aliphatic, cycloaliphatic aromatic disecondary diamine or a blocked amine; (b3) one or more polyester macrodiols having a number of —OH group per molecule equal to about 2; (b4) a mixture formed of two or more compounds (b1), (b2) and (b3).