Use of polyaniline and its derivatives in corrosion protection of copper and silver

This study explores the use of spin-dried polymers such as polyanilines for corrosion and dissolution protection of silver and copper. In particular the parent unsubstituted polyaniline and poly-o-phenetidine are evaluated. The polyanilines were produced by the chemical oxidation of the appropriate aniline monomer. The polymers were dissolved in organic solvents such as N-methylpyrrolidinone and γ-butyrolactone and spin-dryed on the metal surface, followed by a short bake at temperatures below 85°C. The corrosion protection of the resulting structure was determined by electrochemical and inductively coupled plasma (ICP) techniques using water as an electrolyte as well as by an exposure to a temperature/humidity/bias test. Data indicate that depending on the monomer and specific preparation conditions used in the process, the polymerized film could either enhance the corrosion rate or produce a significant corrosion protection.