High dielectric poly(vinylidene fluoride) nanocomposite films with MoS2 using polyaniline interlinker via interfacial interaction

Abstract

A new route for the synthesis of low cost, flexible, high dielectric constant functional polymer nanocomposite is successfully fabricated by introducing molybdenum disulfide (MoS₂) into poly(vinylidene fluoride) (PVDF) using polyaniline (PANI) as an interlinker. The strategy adopted is to exfoliate MoS₂ (E-MoS₂) by simple sonication of bulk MoS₂ in N,N′-dimethyl formamide (DMF) and in situ polymerization of aniline with E-MoS₂ in water to produce MoS₂–PANI showing novel raspberry type morphology. MoS₂–PANI shows good dispersion in PVDF matrix implying strong interaction onto the PVDF interface, and it acts as a nucleating agent for PVDF crystallization. Synergistic nucleating effect of MoS₂–PANI onto PVDF led to the formation of dominant polar β-phases in the MoS₂–PANI/PVDF (MPF) composite films. With 10% filler content, the MPF material shows 86% polar β-phase PVDF due to its good interaction and dispersion of MoS₂–PANI. The maximum increment of dielectric constant (ε′) of that sample is 586 at 10² Hz, which is 42 times higher than that of neat PVDF and it can be well explained by interfacial polarization along with the formation of nanocapacitor network in PVDF matrix. This intriguing synthesis method of MoS₂–PANI/PVDF nanocomposite will open up new opportunities for fabricating nanostructured polymer composites to produce high dielectric materials.