Preparation of core–shell structured alumina–polyaniline particles and their application for corrosion protection

Abstract

Abstract Polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline (ANI) in the presence of alumina (Al 2 O 3 ) particles. The polymerization of ANI occurred preferentially on the surfaces of the particles, resulting core–shell structured alumina–polyaniline (Al 2 O 3 ‐PANI) particles. Morphology examination showed that with decreasing of the weight ratio of Al 2 O 3 /ANI in the reactants, the thickness of the PANI layer increased and changed from an even surface morphology to a particulate morphology. UV–vis and Fourier transformed infrared (FTIR) spectra indicated that there is no chemical interaction between the PANI layer and the Al 2 O 3 surfaces. The PANI layer adhered well to the particles and can be used as anticorrosive fillers for polymer coatings. Enhanced corrosion protection performance was achieved for the emeraldine base (EB) form of PANI deposited Al 2 O 3 particles (Al 2 O 3 ‐EB) filled epoxy coating on carbon steel in 3.0 wt % aqueous NaCl solution. The particles demonstrate both excellent corrosion protection performance and lower cost, which will be of great importance in practical applications. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4372–4377, 2006