Physical properties, thermal stability, and glass transition temperature of multi-walled carbon nanotube/polypyrrole nanocomposites

Polypyrrole (PPy) was synthesized and doped with 1, 2, 4, and 8 wt.% of functionalized multi-wall carbon nanotubes (MWCNTs) by in situ polymerization. TGA/DTA analysis of nanocomposites revealed an increase in thermal stability by increasing the CNTs wt.%. Measurement of electrical resistivity showed a reduction in the resistivity of the composites at all temperatures. The glass transition temperature (Tg) of the samples was measured using electrical resistivity measurements and showed that by increasing the amount of functionalized MWCNTs in PPy, its Tg was increased. Temperature dependence of resistivity of pressed pure PPy showed that by increasing the pelletization pressure, the Tg increased. Also the hardness of nanocomposites was increased by increasing the MWCNTs wt.%.