Effect of Mechanical Vibration and Impact Loading on the Performance of Poly (Vinylidene Fluoride) Composite

Piezoelectric polymer poly(vinylidene fluoride) (PVDF) is extensively used as sensor and actuator devices owing their excellent piezoelectric and pyroelectric properties. However, the melting point of PVDF is relatively low and the service temperature of PVDF is up to 100°C. This restricts the use of PVDF in high temperature applications. This can be improved by adding appropriate fillers to the PVDF. In the present study, a composite of PVDF-Onium salt was developed and characterized to improve the thermal efficiency of PVDF for high temperature applications. In order to investigate the presence of β-phase, which is necessary for sensor applications, X-ray diffraction, scanning electron microscopy, differential scanning calorimetry, Raman and infrared spectra, and dielectric test were used to characterize PVDF-Onium salt composite films made using the solvent cast method. The melting point of PVDF-Onium salt composite was found to be higher (175°C) as compared to the PVDF polymer alone (168.2°C) which has been discussed in detail. The PVDF-Onium salt composite sensors were further tested for dynamic strain sensing application for the first time. The modes of cantilever beam vibrations and the impact loading effects were recorded in order to assess the performance of these sensors.