Enhancing dielectric and mechanical behaviors of hybrid polymer nanocomposites based on polystyrene, polyaniline and carbon nanotubes coated with polyaniline

Abstract

The dielectric and mechanical properties of hybrid polymer nanocomposites of polystyrene/polyaniline/carbon nanotubes coated with polyaniline (_PCNTs) have been investigated using impedance analyzer and extensometer. The blends of PS/PANI formed the heterogeneous phase separated morphology in which _PCNTs are dispersed uniformly. The incorporation of a small amount of _PCNTs into the blend of PS/PANI has remarkably increased the dielectric properties. Similarly, the AC conductivity of PS/PANI is also increased five orders of magnitude from 1.6 × 10⁻¹⁰ to 2.0 × 10⁻⁵ S∙cm⁻¹ in the hybrid nanocomposites. Such behavior of hybrid nanocomposites is owing to the interfacial polarization occurring due to the presence of multicomponent domains with varying conductivity character of the phases from insulative PS to poor conductor PANI to highly conductive CNTs. Meanwhile, the tensile modulus and tensile strength are also enhanced significantly up to 55% and 160%, respectively, without much loss of ductility for three phase hybrid nanocomposites as compared to the neat PS. Thereby, the hybrid nanocomposites of PS/PANI/_PCNTs become stiffer, stronger and tougher as compared to the neat systems.