Structural and Dielectric Properties of PVDF/6A Clay Nanocomposites

摘要

The paper describes the study of structural and dielectric properties of PVDF blended with organically modified clay. The PVDF/clay nanocomposites are prepared by simple melt mixing method. The prepared nanocomposites are characterized for structural and dielectric properties. The structural characterization done using X-ray diffraction and infra-red spectroscopy techniques indicates the crystallization of ferroelectric β phase in nanocomposites. The dielectric study shows the composition-dependent significant enhancement in the dielectric permittivity, particularly in the low-frequency region. The enhancement in the dielectric permittivity is explained on the basis of increase in the conductivity and formation of minicapacitor-like network in the nanocomposites. The dielectric loss spectra of PVDF shows two relaxations corresponding to the glass transition temperature and crystalline relaxation. In case of PVDF/Clay nanocomposites, the dielectric relaxation corresponding to the crystalline relaxation completely disappears, which is attributed to the dielectric manifestation of ferroelectric β phase in nanocomposites. The observed dielectric permittivity data can be very well fitted using Vo-Shi model, which takes contribution of interphase to the dielectric permittivity. The enhancement in the dielectric permittivity along with ferroelectric β phase in PVDF/clay nanocomposites brings the potential application in energy storage devices.