Patent ID: 8273845

Claim:
A soft, semicrystalline, polyurethane thermoplastic elastomer composition which is comprised of (I) a hydrophobic thermoplastic block copolymer which is comprised of the reaction product of (1) at least one hydrophobic polyol, wherein said hydrophobic polyol is a diacid polyester polyol made with dimerised fatty acids and wherein said dimer fatty acid contains 36 carbon atoms, (2) a polyisocyanate, and (3) at least one chain extender containing 2 to 20 carbon atoms, wherein the hydrophobic polyol has a number average molecular weight which is within the range of about 1,000 to about 4,000 Daltons; wherein the hydrophobic thermoplastic block copolymer has a weight average molecular weight which is within the range of 50,000 to 1,000,000 Daltons; and (II) from 10 weight percent to about 80 weight percent of a mineral oil, wherein said elastomer composition has a specific gravity less than 1.0 g/cc 3 and a Shore A hardness of from 20 to 80.