Phase transformation mechanisms and piezoelectric properties of poly(vinylidene fluoride)/montmorillonite composite

Abstract

Poly(vinylidene fluoride) (PVDF)/montmorillonite (MMT) composite with different MMT contents were prepared by solutions-casting method. The effects of MMT on crystalline structure, morphology, dielectric property, piezoelectric property and phase transformation mechanism were studied. The results showed that acted as effective nucleation agents, the orientation of MMT were almost parallel to the surface of the film. The beta phase in the PVDF matrix was increased and the alpha phase was decreased. Relative dielectric constant and loss of the composite were increased with the increasing of MMT. The d 33 was also increased with MMT, which reached a maximum (5.8pC/N) with 2.0 wt % MMT. The mechanisms of changes in phase transformation and piezoelectric property were proposed based on experiment results.

Influence of nickel ion-doped mullite composite on electrical properties, phase behavior, and microstructure of poly(vinylidene fluoride) matrix

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Poly(vinylidene fluoride) membrane with piezoelectric β‐form prepared by immersion precipitation from mixed solvents containing an ionic liquid

“…PVDF has three main crystal forms, namely, α, β, and γ, respectively. The α‐form is nonpolar, whereas β‐ and γ‐forms are polar and electrically active . Of them, the β‐form is most attractive because of its superior piezoelectric properties.…”