ELECTROCHEMICAL SYNTHESIS AND CHARACTERIZATION OF COMPOSITES OF POLYPYRROLE AND POLYIMIDE
A polyimide resin was used as a matrix for electrodeposition of polypyrrole. The electrodeposition was investigated by using different current densities. Another composite based on poly(amic acid) as a matrix for electrodeposition of polypyrrole demonstrated different electrochemical behavior from the composite based on polyimide. The electrical conductivity of the composite based on poly(amic acid) was higher than that for the composite based on polyimide. IR spectroscopy indicated possible interactions between the poly(amic acid) molecule and polypyrrole in the composite. Composites comprised of polypyrrole dispersed in a polyimide matrix were studied by cyclic voltammetry. It was shown that the polypyrrole/polyimide composite has higher permeability to ions than the polypyrrole-polyamic acid composite. The charge storage ability of the polypyrrole-polyimide composite was found to be higher than that of polypyrrole synthesized under similar conditions. The morphology of the composites on the different sides (facing the substrate and facing the solution) was found to be significantly different. Potential step amperometry was applied to investigate the electrochemical properties of polypyrrole-polyimide composites in order to evaluate the influence of the matrix on the kinetics of charging and discharging processes. Redox behavior of the composites was found to be different from that of polypyrrole, possibly because of the formation of complexes between polyimide and polypyrrole resulting in charge transfer in polypyrrole/poly(amic acid) higher than that in the polypyrrole/polyimide composite material. The charge stored per unit mass of the composite was higher than that of polypyrrole. Polypyrrole-polyimide composites can therefore find application in polymer based solid state batteries and supercapacitors.
School:University of Cincinnati
School Location:USA - Ohio
Source Type:Master's Thesis
Keywords:polypyrrole polyimide composite conducting polymers electrochemical synthesis
Date of Publication:01/01/2002