Test of ferroelectricity in non-stretched poly(vinylidene fluoride)/Clay nanocomposites

We measured of the electric displacement D versus electric field E (D-E) hysteresis loop for non-stretched film samples of poly(vinylidene fluoride) (PVDF)/clay nanocomposites. The film was fabricated by compressing melted pellets followed by rapid cooling. The pellets were prepared by melt-compounding method. For the non-stretched film, we obtained clear D-E hysteresis loops that are clear evidence of ferroelectri city at room temperature. Results of X-ray diffraction pattern analysis indicate that the crystal structure of PVDF in PVDF/clay nanocomposites is similar to the beta-form of pure PVDF. We conclude that the crystallization of beta-form PVDF in PVDF/clay nanocomposites is induced by the epitaxial growth of the beta-form on the surface of clay platelets.