Influence of counter-ions on the protection against corrosion effect of epoxy coatings containg conducting polypyrrole.

Abstract

The conducting potypyrrole doped by thee different dopant (dodecylbenzensulfonic acid, aminotrimethylene phosphonic acid and molydate) was prepared by chemcal oxidative method using ammoniumpersulphate, The polymer obtained was characterized by SEM, TEM and Ranum spectra. The polymer was dispersed in epoxi resin and the corrosion protection property of the coating for steel has been evaluated by open circuit potential measurements and EI15. The result of corrosion test showed that Ppy had a posibility of adherence improvement of the epoxi coating and can self-heal by supply of its positive charge and canter-ions dopant at corrosion metal possitions. So the epoxi coating in the presence of Ppy had protection time more dura hie than the coating without Ppy.