Aniline/p-phenylenediamine copolymer [poly(ANI-co-p-PDA)] was prepared by chemical oxidative polymerization. FTIR and H-1-NMR analysis indicate that the poly(ANI-co-p-PDA) is oligomer with end-capped amino groups, which can cure epoxy resin. The anticorrosion performance of carbon steel (CS) samples coated by epoxy resin coating cured with poly(ANI-co-p-PDA) and epoxy resin coating cured with triethylenetetramine exposed to 5 wt % NaCl and 0.1 mol/L HCl aqueous solution is studied by the potentiodynamic polarization and electrochemical impedance spectroscopy. The results show that the CS coated by epoxy resin coating cured with poly (ANI-co-p-PDA) has more excellent corrosion protection than that of epoxy resin coating cured with triethylenetetramine. Raman spectroscopy analysis indicates that the surface of CS coated by epoxy resin coating cured with poly(ANI-co-p-PDA) forms passive layer, which is composed of alpha-Fe2O3. (C) 2009 Wiley Periodicals, Inc. J Appl Polym Sci 112: 1988-1993, 2009