Synthesis and Characterization of Poly(urethane-ether)s from Calcium Salt of p-Hydroxybenzoic Acid

The synthesis and characterization of calcium-containing poly(urethane-ether)s, having ionic links in the main chain, is reported. Calcium salt of p-hydroxybenzoic acid (HBA-Ca) was prepared from p-hydroxybenzoic acid (HBA) and used as the chain extender in the preparation of calcium-containing poly(urethane-ether)s. Poly(urethane-ether)s, having two different compositions, were prepared by varying the mole ratios of poly(tetramethylene glycol), hexamethylene diisocyanate, and HBA-Ca. The synthesized poly(urethane-ether)s were characterized by infrared spectroscopy, thermogravimetric analysis, and dynamic mechanical analysis. The presence of calcium in the polymer chain was confirmed by energy-dispersive X-ray analysis. The inherent viscosity of metal-containing polymers decreased with the increase in the metal content of the polymer. The introduction of metal into the polymer lowers the thermal stability of the polymers as indicated by the decreased initial decomposition temperature. The glass transition temperature (T(g)) and the storage modulus of the metal-containing polymers increase with the increase in metal content presumably due to the formation of physical crosslink's in the polymer. From the mechanical studies of the polymer, it was observed that the metal-containing polymers exhibit high tensile strength and modulus. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 1946-1952, 2011