Investigating the Effect of Crystallinity on PVDF-PMMA Polymer Blend and Analyzing its Dielectric and Piezoelectric Performance

In this study, a binary polymer blend using Polyvinylidene fluoride (PVDF) and Polymethyl methacrylate (PMMA) were prepared by simple solution casting method. PVDF having good dielectric and piezoelectric properties are in huge demand for applications like energy storage, sensors, actuators. To examine the changes in PVDF’s properties resulting from polymer blending, three different blends were prepared using 20%, 30% and 40% PMMA. Using XRD and FTIR the changes in alpha(α) and beta(β) phases of PVDF for different PMMA percentages were analyzed. It was seen that, β-phase of the blend increases up to 30% PMMA and starts to decrease after that and for 30% PMMA the β-phase content was higher than other samples. From FTIR spectrum, the calculated highest and lowest β-phase content was 63.6% and 53.3% for 30% and 20% PMMA respectively. The piezoelectric coefficient (d33 value) was higher for high PVDF content and decreased as the PMMA content increased. With 20% PMMA, the d33 value was 14.8 pC/N. Maximum dielectric constant was observed for 30% PMMA sample and with the PMMA percentage increment, lower dielectric loss was observed.