SYNERGISTIC EFFECTS BETWEEN BENZOTRIZOLE AND IMIDAZOLE IN CORROSION INHIBITION FOR COPPER IN 3% NaCl SOLUTION
3%NaCl溶液中咪唑和苯并三唑对Cu缓蚀协同作用的研究

The efficiency of imidazole(IM) and benzotriazole(BTA) as corrosion inhibitors for copper in 3%NaCl solution was investigated by weight-loss method. The inhibition efficiency of 100ppm IM for copper was only 47.7%, while the inhibition efficiency of 100ppm BTA for copper was 73 2%. When 70ppm IM and 30ppm BTA were used as complex corrosion inhibitor, inhibition for copper was increased and reached at value of 94.3%. This was beneficial to reduce the deficiency of BTA for its toxicity. Electrochemical polarization curve shows that IM suppressed the cathodic reaction of copper, BTA had inhibition effect for the anodic reaction and the complex inhibitor of IM and BTA suppressed both cathodic and anodic reactions. The molecular structure parameters of IM and BTA were obtained via MM2 forcefield program and PPP-SCF quantum chemical calculation. The electron transfer between IM and BTA was aid to their adsorption and passivity on copper electrode surface. This resulted in the synergistic effects between IM and BTA, improving their protective ability for copper in 3% NaCl solution.