Copper corrosion inhibition by polyaspartic acid and imidazole

This work reveals the corrosion inhibition effect of polyaspartic acid (PASP) and imidazole (IM) on copper in 3wt% aminosulfonic acid acting as mixed-type inhibitor of predominant cathodic effect. Potentiodynamic polarization and electrochemical impedance spectroscopy work prove that at 30 degrees C, 1.0g/L PASP alone gave the best inhibitory effect of 89.8%; the inhibition efficiency could reach up to 95.4% when combining PASP and IM at the same ratio in total of 1.0g/L. The anti-corrosion mechanism of PASP and IM on copper is proposed from the characteristic molecular structures of these two chemicals.