Polymer blend compositions reliant comprehensive study on optical, thermal, structural, and broadband dielectric and electrical properties of P(VDF-HFP)/PMMA films

In developing flexible type advanced electrical and electronic devices, rationally designed excellent performance polymer dielectrics are highly admired in technological industries. To contribute in this field, herein, the entire composition ratios polymer blend (PB) films of poly(vinylidenefluoride-co-hexafluoropropylene) (P(VDF-HFP)) and poly(methyl methacrylate) (PMMA) are prepared following the solution-cast procedure. The prepared PB films are designated as xP(VDF-HFP)/(100-x)PMMA, where x is varied, in steps, as 100, 80, 50, 20, and 00 wt%. The optical, thermal, structural, and broadband dielectric and electrical properties of these PB films are characterized in detail employing advanced instruments and interpreted meaningfully with blend compositions. The ultraviolet-visible (UV-Vis) spectroscopic results confirmed predominantly composition tunable UV absorbance as well as energy bandgap values of these PB films, which decreased when the P(VDF-HFP) amount was relatively reduced. Differential scanning calorimetry (DSC) measurements explained the reduction in the degree of crystallinity and crystallite thermal stability on decreasing the P(VDF-HFP) amount in the blend and also their transformation to amorphous type miscible blend for the compositions having PMMA amount exceeding 60 wt%. The Fourier transform infrared (FTIR) spectra also elucidated the formation of miscible blends for PMMA-rich compositions owing to a large increase in heterogeneous hydrogen bonding. The broadband dielectric spectroscopic measurements over the nine decades of harmonic electric field frequency (20 Hz to 1 GHz range) unveiled the contribution of various polarization processes and their alteration with frequencies that govern the dielectric permittivity and its dispersion, and different relaxations related to the structural dynamics of the blended polymers. The outcome provides a facile strategy to realize the composition reliant dielectric and optical properties of P(VDF-HFP)/PMMA blend films and helps in proposing their feasible applications as innovative optical and dielectric materials for flexible technologies.