Undoped polyaniline anticorrosive properties

The anticorrosive properties of undoped polyaniline (PAni) casted onto mild - and galvanised steels were studied by a classical methodology used for or ganic coatings. Pure PAni, as well as, PAni plus an epoxy topcoat were test ed in total immersion conditions monitored by electrochemical impedance. Th e influence of the substrate and the electrolyte composition were discussed . PAni performance was evaluated in terms of underfilm corrosion and adhesi on loss in comparison with other coating systems. It was shown that undoped PAni did not have good barrier properties and adhesion to the substrates w as very poor. Even with an epoxy topcoat PAni coated samples had the worst performance in comparison with the other coating systems herein used as ref erence. (C) 2001 Elsevier Science Ltd. All rights reserved.