Studies on Transport Properties of Polyaniline-Ferric Oxide Polymer Composites

The polyaniline-ferric oxide (Fe2O3) composites have been prepared for different weight percentage such as 5%, 10%, 15% and 20% of Fe2O3. The polymerization was carried out by in-situ chemical oxidation technique with ammonium persulphate (APS) as an oxidizing agent in aqueous sulphuric acid as dopent under constant stirring at 0-4 oC. The characterization of polymer composites has been carried out by FT-IR, UV-Vis so as to conform polymerization, XRD for elucidating the structure of composites. The morphology of composites was studied by SEM. Temperature dependent D.C. electrical conductivity measurement has been carried by four probe technique in the range of 303-373 K. It has been observed that conductivity of all composites is found to be increasing by increasing temperature. The composites of 5%(PF-1) and 10%(PF-2) has been found to be more while composites 15%(PF-3) and 20%(PF-4) has found to be lower than that of pure PANI over entire temperature range. The enhancement in conductivity of PF-1 and PF-2 composites may be due to uncoiling of polymeric chain due to strong interaction of PANI with Fe2O3 crystallites as suggested by FT-IR and XRD studies. Lowering in conductivity of PF-3 and PF-4 may be due to increasing the content in composition which gradually weakened interaction between PANI and Fe2O3; leads to free PANI Chain coexist in the composites and may be due to the particle blockage in conductive path by additive embedded in PANI matrix.