Thermoplastic polyurethane elastomer based on a hydroxyl terminated

Abstract

A thermoplastic polyurethane elastomeric seal composition comprising, by weight, about 90% to 99% thermoplastic polyurethane elastomer and about 1% to 10% fibers. Also, the thermoplastic polyurethane elastomer is derived from the reactants comprising: (i) a mixture of polyol and an aromatic chain extender in a molar ratio in the range of from about 40:60 to about 60:40 of butanediol glycol adipate to hydroquinone bis 2-hydroxyethyl ether, and (ii) 1,5 naphthalene diisocyanate present in a molar ratio in the range of about 50:50 to about 54.5:45.5 of 1,5 naphthalene diisocyanate to the said first mixture of polyol and an aromatic chain extender. After curing, the thermoplastic polyurethane elastomeric seal compound has outstanding wear resistance and low compression set. This thermoplastic polyurethane elastomeric seal compound is particularly useful in making shaft seals subject to high wear and high pressure, for use in hydraulic rams in earthmoving equipment.