Investigation of piezoelectric effect and thermally stimulated depolarization current of poly (vinyl chloride–co-vinyl acetate–co-2-hydroxypropyl acrylate)/poly (vinylidene fluoride-trifluoroethylene) polymer blend

Abstract

DSC measurements revealed that the ferroelectric-paraelectric (F-P) transition point of PVDF-TrFE has been affected after blending with PVVH. XRD pattern and FTIR spectra of PVVH, PVDF-TrFE, and their polyblend samples are analyzed to investigate the effect of PVVH on the enhancement of crystallinity and β-fraction of PVD-TrFE. The piezoelectric coefficient (d₃₃) of PVVH/PVDF-TrFE polymer blend has been investigated under different parameters, such as the temperature, applied stress, and composition. It is found that the value of d₃₃ has been improved either with increasing temperature or increasing applied pressure for all samples. The maximum values of d₃₃ at 0.62 MPa and 353 K are 1.01, 9.93, and 12.84 PC/N for pure PVVH, PVDF-TrFE, and 30/70 PVVH/PVDF-TrFE, respectively. TSDC of pure PVVH, PVDF-TrFE, and their polyblend samples has been studied in a wide range of temperatures at different poling electric fields. The results revealed that TSDC of pure PVVH is characterized by a dipolar relaxation peak centered at 351 K, whereas, pure PVDF-TrFE showed two peaks at 327 K, and the other is observed in the temperature range from 358 to 371 K. TS technique has been applied for decomposing TSDC spectra of all samples to its elementary peaks. It was verified that the compensation effect is operated for all samples and all thermodynamic parameters, such as ΔS, ΔH, and ΔG were calculated from the relaxation map analysis (RMA).

Keywords:

• Piezoelectric coefficient
• PVVH
• PVDF-TrFE
• TSDC
• compensation

Additional information

Funding

This work was performed under the financial support of our project from “Research Unit of Mansoura University, MU-SCI-21-23.”