Flexible conducting polyaniline/polyacrylonitrile composite films

Conducting polymers have been expected as promising transducers for chemsensors and biosensors owing to their unique electrical, electrochemical and optical properties. However, potential applications of these polymers are restricted by poor mechanical properties-low strength and high brittleness. The most efficient solution of this problem is to elaborate composite systems where a polymer support provides good mechanical properties, and a conducting polymer acts as an active component. Now a new method of making polymer films with conductive surfaces by permeation of the conducting guest species into the host is reported. The flexible polyaniline (PANI)/polyacrylonitrile (PAN) composite films were successfully prepared by permeation of the aniline monomers into the solution of PAN in dimethyl sulfoxide and one-step in-situ polymerization of aniline monomers from and in microporous PAN layer. The existence of a layered structure was shown by attenuated total reflection Fourier transform infrared spectroscopy and scanning electron microscopy. Good adherence between PANT and PAN benefited from the formation of a continuous gradient network in the film thickness along the capillary. The electrical conductivity of the resulting composite film was also determined.