Free volume dependence of the dielectric constant of poly(vinylidene fluoride) nanocomposite films.

The free volume effects on the dielectric properties of the polymer are ambiguous, and the quantitative effect of free volume on the dielectric properties has rarely been systematically studied, especially in the high-elastic state dipolar (HESD) polymer. In this work, the free volume of dipolar poly(vinylidene fluoride) (PVDF) is regulated by the addition of AlO, which greatly increase the size of free volume holes. Then the effect of free volume on the dielectric properties of PVDF/AlO composites is discussed.

Optimizing nanostructures to achieve enhanced breakdown strength and improved energy storage performances in dipolar polymers.

Polymer dielectrics have attracted ever-increasing attention for electrical energy storage applications in recent years. Typically, polymer-based nanocomposite films are adopted to obtain polymer dielectrics with high energy density but sometime suffer from the inhomogeneous distribution of fillers. In this work, enhanced breakdown strength, suppressed dielectric loss and improved energy storage performances of PVDF film are concurrently achieved the regulation of the sub-nano free volume, without introduction of any kinds of fillers and also minimizing the uneven distribution of the local electric field.