Ultra-Textured Active polymer (UTAP) Composite for High-Performance Intelligent Acoustic Transducers

This Small Business Innovative Research Phase I project seeks to combine the enhanced piezoelectric properties of single crystal perovskite ferroelectrics, recently discovered at Pennsylvania State University, with the electrostrictive properties of polyurethane to make a new class of "smart" materials for acoustic transducers. A tape casting process is used to form composite sheets compromising highly oriented platelets of hydrothermally grown single-crystal lead texture, so achieved, greatly enhance poling efficiency. Composite sheets are combined with polyurethane sheets to form a transducer plate. By using an electromechanically active polyurethane matrix we not only improve the acoustic impedance match between the composite material and water, but also improve signal/noise ratio and acoustic projection power. Furthermore, since piezoelectric and electrostrictive materials are the enabling component in "smart" actuator/sensor systems for adaptive control, the electrostrictive response of the polyurethane can be used in an actuator mode, independent of the piezoelectric response of the crystal phase, to make an adaptive acoustic transducer. Thus, the polymer matrix can distort itself in controlled ways for the purpose of beam steering or to suppress unwanted resonances.