Piezoelectric-piezocapacitive hybrid sensor based on electrospun Poly(vinylidene fluoride)-Poly(octafluoropentyl acrylate)-sulphonated Poly(phenylene sulfide) blend nanofiber

Abstract In this study, sulfonated Poly(phenylidene sulfide) (sPPS) of varying content (0, 3, 5, 7 and 10 wt.-%) is used as a filler to study the β-crystalline phase changes in electrospun Poly(vinylidene fluoride) (PVDF)-Poly(octafluoropentyl acrylate) (POFPA) blend (90/10 ratio, abbreviated as P-PFA) nanofiber. FTIR and XRD studies confirmed the changes in P-PFA crystalline phases as a function of varying sPPS content, and among them, 5 wt.-% sPPS content exhibited a maximum increase in β-crystallinity. SEM micrographs of P-PFA/sPPS confirmed the appropriate formation of nanofibers with average fiber diameters of around 90 ∼ 150 nm. Using electrospun neat P-PFA and P-PFA/sPPS blend nanoweb fibers, piezoelectric sensors were fabricated and measured for output voltage signals. Among the five different samples, P-PFA/sPPS (5 wt.-%) exhibited higher output voltage (Vp-p = 1.2 V) than neat P-PFA (Vp-p = 0.4 V), revealing the nucleating effect of sPPS in P-PFA. The unexpected values obtained in the tensile strength (35.09 ± 0.102 kPa) and capacitance hysteresis (Cmax = 0.158 nF) of P-PFA/sPPS (5 wt.-%) sample opens up the possibility of using this material as a flexible hybrid sensor capable of measuring both piezoelectric and piezocapacitive signals.