Abstract: A polymer comprising a poly(urethane)ureamide is prepared by a reaction of a polyisocyanate and a polyesterpolyol derivative of the formula [I] ##STR1## wherein A is an n-valaent radical obtained by removal of terminal hydrogen atoms from an n-valaent polyester-polyol having a molecular weight of 400 to 10,000 and containing ##STR2## group in the main chain, n is an integer of 2.ltoreq.n.ltoreq.4,x is an average value and a number of 0.ltoreq.x.ltoreq.(n-1),--NH-- group of ##STR3## in the main chain forms an amido group connected with a carbonyl group of an aminobenzoic acid and/or a carbonyl group of a polybasic acid component of the polyesterpolyol and,--CO-- group of ##STR4## in the main chain forms an ester group or amido group. The polymer has higher heat resistance and greater mechanical strength as compared to corresponding polyester-urethanes.

Abstract: A poly(urethane)ureamide which comprises a polymer obtained by a reaction of (a) a polyether derivative of the general formula [I] and (b) a polyisocyanate exhibits an excellent wear resistance and heat resistance due to the presence of the aromatic amido groups ##STR1## wherein A is an n-valent radical obtained by removal of hydroxyl groups from an n-valent polyoxyalkylenepolyol having a molecular weight of 400 to 10,000,n is an integer of 2 to 8,x is an average value and a number of 0.ltoreq.x<(n-1) andy is an average value and a number of 0.05.ltoreq.y<1.

Abstract: A polyetherpolyol derivative having at least, on average, one terminal amino group in which at least, on average, one hydroxyl group is substituted by a residue of para-aminobenzoic acid ester, and having the general formula ##STR1## wherein n is an integer of 2 to 8, x is an average value and a positive number of 0.05n to (n-1), A is an n-valent radical obtained by removal of hydroxyl groups from an n-valent polyoxyalkylenepolyol having a molecular weight of 400 to 10,000.

Abstract: A polyurethaneurea which comprises a polymer obtained by a polyaddition reaction of (a) a polyetherpolyol derivative and (b) an at least 2-valent polyisocyanate, the polyetherpolyol derivative having at least, on average, one terminal amino group in which at least, on average, one hydroxyl group is substituted by a residue of para-aminobenzoic acid ester, and having the general formula ##STR1## wherein n is an integer of 2 to 8, x is an average value and a positive number of 0.05 n to (n-1), A is an n-valent radical obtained by removal of hydroxyl groups from an n-valent polyoxyalkylenepolyol having a molecular weight of 400 to 10,000.