Preparation of conducting composites and studies on some physical properties

A thick and large conducting composites was prepared by the inclusion of conducting polyheterocyclic polymer in the highly porous cross linked polystyrene. The inclusion of conducting polymer in the host polymer, prepared by a concentrated emulsion polymerization, was carried by the two step imbibition technique. A FeCl₃-methanol system leads to conductivities of polypyrrole and polythiophene impregnated composites of 0.82 and 4.20 S/cm, respectively. The environmental stability of polythiophene impregnated composites is better than that of polypyrrole impregnated composites. The EMI shielding effectiveness of polythiophene impregnated composites reaches 23 dB at 1.0-2.0 GHz. In temperature range of 20-300 K, polypyrrole impregnated composite exhibits semiconducting behavior and the data fits in the VRH model for charge transport.