Polyurethane electrostriction

A phase mixed thermoplastic polyurethane elastomer is provided for use in tranducers including underwater transducers, sonars and other electrostriction driven devices. The thermoplastic polyurethane elastomer includes an isocyanate, a butanediol, a polytetramethylene ether glycol, and a polyhydric alcohol. The thermoplastic polyurethane elastomer being made by adding the polytetramethylene ether glycol to isocyanate to form a mixture, then holding said mixture of the polytetramethylene ether glycol and isocyanate to a predetermined temperature for a predetermined time, degassing the mixture and sealing the mixture, measuring the percent free isocyanate to a predetermined molar ratio with the polytetramethylene ether glycol, chain extending the mixture into a first polymer with the butanediol and the polyhydric alcohol, adjusting the stoichiometry of said chain extender to a predetermined isocyanate index to avoid crosslinking, and postcuring the resin of the first polymer for a predetermined time and temperature.