Study of dielectric properties of polypyrrole prepared using two different oxidizing agents

Polypyrrole samples that have been prepared in a conducting state by a chemical method using two different oxidizing agents, ferric chloride and potassium persulphate, in different concentrations have been transformed to a dielectric state by heating at 333 K for 7 days and then at 353 K for 4 days more. Then the frequency and temperature 32 dependence of the dielectric constant epsilon', loss tangent tan delta and AC conductivity sigma' were investigated using a complex impedance technique. It has been found that the concentrations of the reactants used in the preparation have a noticeable effect on the dielectric properties. It has been concluded also that heating at constant temperature has enhanced the resistivity of the samples, which can be considered as a simple method of obtaining polypyrrole (PPy) in a dielectric state rather than more complex electro-chemical methods which may be useful in some future applications such as the manufacture of supercapacitors. (c) 2006 Wiley Periodicals, Inc.