Influence of Hot‐Press Temperature on β‐Phase Formation and Electrical Properties of Solvent‐Casted PVDF‐HFP Co‐Polymer Films Prepared from Two Different Solvents: A Comparison Study

Abstract

Poly(vinylidene fluoride)‐co‐hexafluoropropylene (PVDF‐HFP) co‐polymer films are prepared via solution casting followed by hot‐press method. Two different types of solvents, viz., solvent mixture DMF and acetone and single solvent only DMF are used to prepare two sets of samples which are then hot‐pressed at various temperatures (110, 120, and 130 °C) to study the effect of hot‐press temperature on samples prepared from different types of solvents. X‐ray diffraction (XRD) and Fourier transform infrared (FTIR) spectra shows formation of electroactive β‐phase whose fraction remaining above 71% for all the synthesized samples. Differential scanning calorimetry (DSC) is performed to obtain the degree of crystallinity of the as‐prepared samples and the hot‐pressed samples seemed to have a single exothermic melting peak instead of two in case of the casted ones. Dielectric properties and AC conductivity of the samples are also studied. The highest dielectric constant among the synthesized samples is found to be ≈12 at 1 kHz at room temperature. The static hysteresis loops are traced for all the as‐synthesized films. Remnant polarization is found to increase with increase in the hot‐press temperature, the coercive field remaining almost similar for all of them. The PUND analysis is also carried out for the all as‐prepared samples. A comparison study is presented through this report, emphasizing the influence of hot‐press temperature on β‐phase fraction of PVDF‐HFP films prepared from two different types of solvents, intended for energy harvesting and storage applications.

Advances in P(VDF-TrFE) Composites: A Methodical Review on Enhanced Properties and Emerging Electronics Applications

“…A dielectric constant of 46.4 was obtained for 100 Hz with a dielectric loss of 0.07 for 15 wt% of the nanocomposite due to the strong interfacial compatibility raised due to the hydrogen bond between the polydopamine segment and molecular chain. The energy density of 3.3 J/cm 3 The solvents are evaporated during rotation and the dry film of the polymer is formed. The solution casting method is based on Stoke's Law.…”

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“…It was observed that the polymers do not interact chemically with the additives, whereas the adhesion of starch is better in the copolymer. The density values of the blended films are between 1.5 and 2.0 g/cm 3 and thermal conductivity was in the range of 0.17-0.32 W/mK. Li et al fabricated electrospun P(VDF-TrFE) scaffolds for bone and neural tissue engineering [135].…”

“…Piezoelectric polymers have high dielectric breakdown strength, flexibility, and cost-effective fabrication routes. Even though they have comparatively low piezoelectric coefficient than ceramics, their high mechanical flexibility and biocompatibility help them to find a place in various technical application [1][2][3][4][5][6].…”

Fabrication and characterization of PZT/PVDF composite films for force sensor applications

“…Composites can show high dielectric permittivity, flexibility, breakdown strength and low weight, which are often unattainable in a single-phase ferroelectric material. 22 Several critical parameters, 23 including preparation method, 24 particle size, 25 filler percentage, 26 thickness 27 and operating temperature, 28 have a substantial impact on the electromechanical and mechanical properties of piezoelectric composites. In this case, PZT/PVDF composite film consists of PZT particles as fillers and PVDF as the polymer matrix in a solution.…”