Corrosion Inhibition Properties of Dodecylbiguaniding Salt (DODH) for Copper

Dodecylbiguanidine salt(DODH)was synthesized by nucleophilic addition reaction using dicyanodiamde and aliphatic amine as raw materials.The compound was characterized by FT-IR,and the corrosion inhibition effect of DODH on copper was investigated by means of static weight loss and potentiodynamic polarization in 5% HCl,5% NaHCO3 and 3% NaCl solutions.The results showed that the best corrosion inhibition effect of DODH on copper was in 5% NaHCO3,inhibition efficiency was 98.4% at 100 mg/L;the inhibition efficiency was 79.3% at 100 mg/L in 5% HCl;but the inhibition efficiency was common in 5% NaCl.Polarization curve results showed that DODH was a kind of mixed-type inhibitor,but the inhibition effect for cathodic reaction was dominant.