Tailored ferroelectric responses and enhanced energy density in PVDF‐based homopolymer/terpolymer blends

Abstract

Blend of polymers is an effective way to tailor the ferroelectric responses and improve the energy storage properties of polymers. In this work, the microstructure and dielectric responses of the blends of poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) [P(VDF-TrFE-CFE)] have been studied. It is found that the addition of PVDF disturbs the crystallization process of P(VDF-TrFE-CFE), leading to lower crystallinity and smaller crystalline size. The aforementioned microstructure changes result in tailored ferroelectric responses. Dielectric responses show that the blend with 10 wt % PVDF achieves larger polarization response under high electric field (above 300 MV/m) due to the interfacial polarization. Because of the tailoring effect and the interfacial polarization, the blend with 10 wt % PVDF exhibits higher energy density and efficiency. Moreover, the breakdown strength (E b ) is also improved by adding a small amount of PVDF into the terpolymer. V C 2014 Wiley Periodicals, Inc. J.Appl. Polym. Sci. 2014, 131, 40994.

Static and dynamic electro-optical properties of liquid crystals mediated by ferroelectric polymer films

“…The observed current–voltage curves shown in Fig. 1 and 2 are in agreement with existing literature reporting the polarization – electric field loops 46,47 and an increase in the coercive field measured in PVDF-based films at high frequency as compared to the same values at low frequency. 48,49 For example, by changing frequency from 10 Hz to 100 kHz, the coercive field increased from less than 100 MV m −1 to more than 200 MV m −1 .…”

Localized Fretting-Vibrotactile Sensations for Large-Area Displays

“…Even though the strain increases at elevated temperatures, the film stress at 60 °C decreases to almost half of that at 25 °C. Therefore, the decrease of the actuation performance (displacement) at the elevated temperature is mainly caused by the decrease in the Young’s modulus of the neat P­(VDF–TrFE–CFE) film . The addition of Co75 decreases the film stress, whereas the addition of Co55 tends to increase the film stress.…”

“…This should be considered for the durability of devices. Blending relaxor ferroelectric (RF) P­(VDF–TrFE–CFE) or P­(VDF–TrFE–CTFE) with a small amount (typically less than 30%) of poly­(methyl methacrylate), poly­(vinylidene fluoride–chlorotrifluoroethylene) [P­(VDF–CTFE)], − PVDF, , or P­(VDF–TrFE) , has been reported to enhance some electromechanical properties, such as the polarization response, dielectric constant, elastic modulus (i.e., elastic energy density), and breakdown strength. However, not much attention has been given to the strain response of blended RFPs.…”

Ferroelectric Fractional‐Order Capacitors

“…FTIR and XRD confirm that the blends contain P and TP in their pristine forms, such that without forming any additional complex molecular structure in the blend. Nonetheless, the change in the microstructures in the blend, which are responsible for the change in electrical properties such as polar conformation, could not be discarded …”