Composite of polyaniline containing iron oxides

A composite of polyaniline (PANI) containing iron oxides with nanometer size was prepared by a chemical method. Polymer adsorption on the surface of magnetite particles was investigated. The electrical and ferromagnetic properties of the composites were measured as a function of the pH value of the reaction solution during polymerization. The conductivity of the composites at room temperature decreases with the increase of the pH as the doping level in the composite decreased. For the basic preparation conditions, the resulting PANI-FexOy composite can be attracted by a magnet at room temperature and shows an insulating behavior. Doping of PANI with acids leads to electrical conducting properties of ferromagnetic composites. (C) 2004 Elsevier B.V. All rights reserved.