An investigation of the electrostrictive property of PZT/polyurethane particulate composites

Particulate composites of the thermoplastic polyurethane (TPU) elastomer and the lead zirconate titanate (PZT) ferroelectric particles were prepared by solution casting in dimethylformamide (DMF) and then hot pressed to form thin film. X-ray diffraction results reveal the phase segregation in pure TPU was suppressed in composites. A modified Michelson interferometer has been employed to measure the electric field induced strain in thickness direction of the samples. Electrostriction coefficients of the composite decrease with increasing PZT content at low electric field. Strain reversal was observed at high electric field for the composites of more than 8 vol% PZT, it is attributed to the polarization reversal of the PZT in the composites.