Kinetics of polymerization of polypyrrole in dielectric matrices probed by electrical impedance spectroscopy

In this work, we describe the use of electrical impedance spectroscopy to investigate not only the process of absorption of monomers of pyrrole in films of conventional polymers, but also the kinetics of their subsequent polymerization in the interior of dielectric matrices of this kind. By exposing the matrix to pyrrole vapor and monitoring the in situ dielectric response of the composite system, as the polymerization proceeds we can observe the gradual increase in the number of percolation pathways for the electrical current by following the associated shift in the frequency of the dielectric relaxation of the polymeric blend formed. By comparing the different rates in which these mechanisms occur, we can estimate how easily the polypyrrole (PPY) chains are formed in the interior of distinct dielectric matrices, establishing in this manner the relative feasibility of use of these polymeric blends as convenient materials in molecular electronic devices.