Synthesis and Electrical Characterization of Self-Supported Conducting Polypyrrole-Poly(vinylidene fluoride) Composite Films

We report the synthesis of polypyrrole composite films by chemical oxidation polymerization of pyrrole dif- fused inside poly(vinylidene fluoride) matrix and temperature dependant dc conductivity study of these composite films. Ammonium persulfate is used as an oxidizing agent and HCl as the dopant in aqueous medium. This technique produces highly conductive, flexible and free standing polymer composite films in semi-interpenetrating architecture. It is observed that conductivity of the composite films can be controlled by varying the dopant concentration. The variation of conduc- tivity with temperature indicates the semiconducting nature of these composite films. The temperature dependence of conductivity is explained in the light of two different models from which activation energy (Ea) and other hopping pa- rameters are determined. Experimental data fits well with variable range hopping model and three dimensional charge transport mechanism is shown to occur in these films.