Poly(2,5-dimethoxyaniline) Film for Corrosion Protection of Iron

摘要

Among the various materials used for the anti-corrosion of metals, conductive polymer film coatings are some of the most effective, cheapest and also the most environmentally friendly materials (1). Even though pinholes and/or cracks are formed in the coatings, the anti-corrosion ability is only slightly decreased because of the features of the anti-corrosion coatings. The coatings are said to simply serve as an in-situ oxidant or anodic protectant (2). When the coating oxidizes the metal surface to which it is in contact, the coating is reduced. Since the reduced coating is re-oxidized by ambient air, it continues to oxidize the metal surface and the passive state is maintained. Among the conductive polymers, it is widely recognized that polyaniline (PANI) is one of the best candidates of conductive polymers for an anti-corrosion coating since the anti-corrosion ability was found (3,4). Although numerous studies about the anti-corrosion ability of PANI (4-19), the effort to enhance its ability is necessary for practical use (4-19). For example, the adhesion problem must be solved. The adhesion of an electro-deposited PANI coating is generally quite poor on iron and steel (20).