Preparation of organosilicate/PVDF composites with enhanced piezoelectricity and pyroelectricity by stretching

Organosilicate (OS)/poly(vinylidene fluoride) (PVDF) composites containing 2 and 4 wt% OS were prepared by the melt-blending method. It was confirmed by scanning electron microscopy that OS was homogeneously distributed in the PVDF matrix. The results of differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and wide angle X-ray diffraction indicated that the incorporation of OS along with stretching treatment could effectively transform PVDF crystallization from the stable α phase to the most useful electroactive β phase. The interfacial interaction between PVDF and OS was analyzed by X-ray photoelectron spectroscopy and zeta potential. The dielectric properties, AC conductivities, mechanical properties, Rockwell hardness, and thermal conductivity of resultant OS/PVDF composites have been measured. More importantly, the piezoelectric coefficient d33 and pyroelectric coefficient p of stretched OS/PVDF composites were enhanced significantly in comparison with the pure PVDF, making them promising materials for self-powered electronic systems, thermal detectors, sensors, and actuators.