Improved Thermal and Electrical Properties of Nanocomposites Based on Poly(vinyl pyrrolidone)/Poly(acrylonitrile)/Multiwalled Carbon Nanotubes.

Poly(vinyl pyrrolidone)/Poly(acrylonitrile)/multi-walled carbon nanotubes composites (PVP/PAN/MWNTs) were fabricated by a simple solution cast technique with a wide composition range from 0 to 3.12 wt% of MWNTs. The nanocomposites were characterized by fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM). A percolated MWNTs network structure and relatively good dispersion of MWNTs are evident in PVP/PAN/MWNTs nanocomposites with 3.12 wt% of MWNTs. The thermal properties of the polymer blend with MWNTs were carried out by means of different scanning calorimetry (DSC). It indicated that the incorporation of MWNTs had a significant influence on crystallization and melting behaviors for the polymer nanocomposites. The four point probe method was used to measure the electrical conductivity, and the result showed ionic conductivity of the order of 2.87 × 10^-4 S/cm to 1.91 × 10^-2 S/cm. The effect of the concentration of the filler on the conductivity of the polymer nanocomposite was discussed. Nanocomposites based on PVP/PAN and MWNTs as filler show a significant enhancement in the electrical conductivity as a function of temperature. The low percolation threshold in PVP/PAN/MWNTs nanocomposites was explained by high aspect ratio of the nanotubes and their distribution inside the polymer blend.