Inhomogeneous charge transport in conducting polyaniline

We report charge transport studies of two composite systems, CSA-doped polyaniline (CSA-PAN) in Nylon-12 blends and TSA-PAN coated carbon blacks (CB). The CSA-PAN/Nylon samples showed a temperature dependent insulator-metal transition and an anomalous high microwave absorption while the TSA-PAN/CB samples showed an unusual insulator to metal transition from the individual materials to the composites. We propose that the common scheme in these results is the inhomogeneous charge transport due to the formation of ordered regions (''metallic islands'') during the polymerization of conducting polyaniline in both composites.