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 ferroelectricity 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 β-form of pure PVDF. We conclude that the crystallization of β-form PVDF in PVDF/clay nanocomposites is induced by the epitaxial growth of the β-form on the surface of clay platelets.