Conductive copolymers of polyaniline, polypyrrole and poly (dimethylsiloxane)

Two step electrochemical polymerization method was used to obtain various conductive homopolymers, composites and copolymers of Polyaniline (PAn), Polypyrrole (PPy) and Poly(dimethylsiloxane) (PDMS). PAn/PPy, PDMS/PAn/PPy, PPy/PAn and PDMS/PPy/PAn conductive polymer films were synthesized with different compositions and their properties were compared. Films were characterized by conductivity measurements, cyclic voltammetry (CV), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. When both PPy and PAn existed in the films, the major contribution to the conductivity was due to the PPy component. PDMS/PPy/PAn films were more conductive than PDMS/PAn/PPy films similar to their binary counterparts without PDMS. When PPy was coated over PAn, thermally more stable films were obtained than the films synthesized in reverse order. The characterization tests implied the formation of chemically bounded new structures such as crosslinking copolymer structures. SEM microphotographs of PDMS/PAn/PPy films indicated a clear double layer structure. Hence, changing the order of coating had significant effects on the structure and properties of films. (C) 2005 Elsevier B.V. All rights reserved.