Structurally Induced Dielectric Constant Promotion and Loss Suppression for Poly(vinylidene fluoride) Nanocomposites

An increase in the dielectric constant (800 ± 15; 10 0 ≤ f ≤ 10 4 Hz) of PVDF without a coresponding increase in the dielectric loss is reported. This is realized by preparing sandwich structures composed of CNF/PVDF composite layers and a pure PVDF interlayer. The influence of the interlayer thickness on the dielectric properties is investigated. It is shown that a 30 µm interlayer is sufficient to prevent formation of the conductive network in the sandwich structures that would result in lower loss. It is demonstrated that with better CNF dispersion, a further increase of the dielectric constant and a lower loss can be obtained simultaneously. The sandwich approach thus leads to nanocomposites with enhanced dielectric constants while maintaining low loss. magnified image