Photo-induced polymerization of polyaniline

A straightforward route to prepare polyaniline is presented in which photons and metallic ions replace conventional oxidants to promote polymerization of aniline monomer. The photopolymerization methods yield a composite material that has been characterized by its UV, visible and Raman spectroscopic analysis and by scanning electron microscopy and X-ray microanalysis as well. Intriguing forms of silver wires embedded in polyaniline are observed, typically of 1 mum wide and up to 100 mum long. It is shown that the morphology of the resulting conducting polymer strongly depends on the excitation wavelength, while a globular morphology is found for the UV synthesis and a fibrillar one is found for visible light excitation. (C) 2003 Elsevier Inc. All rights reserved.