Fabrication and Characterization of PVDF - PZT (Navy type-VI) 3-0 Composites

Abstract

Ferroelectric polymer–ceramic composites are promising materials for transducer applications, high-energy-density capacitors, and are widely used in underwater hydrophones, biomedical imaging with ultrasound, and nondestructive testing applications. The critical factor in the 3-0 composite is to ensure homogeneous distribution of the filler in the matrix.Combination of high-permittivity, high piezoelectric property with high-dielectric-strength polymer hosts offers high-performance composite materials. The present paper describes the fabrication of ceramic-polymer composite of PZT (Navy Type VI) nanoparticles as fillers, PVDF polymer as a matrix and DMF as a solvent. Phase, microstructure, dielectric and mechanical properties were investigated by XRD, FESEM, LCR meter and UTM, respectively of solution cast PVDF-(0 to 50 Vol%) PZT film. The XRD pattern indicates the pure PVDF existed in a mixed α, β phase. Their peak intensities decrease with increasing ceramic volume fraction, and PZT structure is unaffected by the presence of PVDF.The density of the composite samples is found to increase from 2.2 to 4.5 g/cc with the increase of volume fraction of PZT (10-50 vol%). The relative permittivity(εr) increases with increase in the volume fraction of filler material at all frequencies under study. The observed value of relative permittivity was as high as 100 and at 1 kHz in as cast samples for 40 vol% PZT. The microstructure of composites showed a homogeneous distribution of PZT fillers within the PVDF matrix.From the tensile testing, we observed that the flexibility of the composite film could be retained up to 50 Vol.% ceramic loading.