Transport properties in polypyrrole–PVA composites: Evidence for hopping conduction

Abstract
Experimental results on electrical conductivity and thermoelectric power for FeCl3‐doped polyvinyl alcohol‐polypyrrole composites, with polypyrrole content exceeding the percolation threshold, are presented. The electrical conductivity is analyzed in terms of the hopping theory, whereas the thermoelectric power displays a metallic‐like dependence. A model involving both the intrinsic resistance of the fibrils (V.R.H. hopping mechanisms) and the resistance of the junctions between fibrils (fluctuations‐induced tunneling conduction) has been retained.