Corrosion protection of copper using polypyrrole electrosynthesised from a salicylate solution

Reproducible electrodeposition of adherent and homogeneous polypyrrole was achieved on copper from a salicylate solution. The process was facilitated by the formation of a passive layer which inhibited further dissolution of copper but was sufficiently conducting to allow electropolymerisation. The deposited polymer adopted the characteristic cauliflower morphology. The corrosion protection properties of the coating were assessed using polarisation plots, Tafel analysis, OCP measurements and electrochemical impedance spectroscopy in 0.1 and 0.6 M (3.5% w/v) NaCl solutions. The polymer coating was effective in protecting copper and was stable for periods exceeding 2 weeks of immersion in 0.6 M NaCl. (C) 2012 Elsevier Ltd. All rights reserved.