Performance of EP/PpPDA and EP/PpPDA/SiO2 nanocomposite on corrosion inhibition of steel in hydrochloric acid solution

摘要

Epoxy-poly p-phenylendiamine (EP/PpPDA) and its nanocomposite with SiO2 nanoparticles (EP/PpPDA/SiO2) were synthesized and tested as potential corrosion inhibitors of steel in 1 M HCl solution. Performance of EP/PpPDA/SiO2 and EP/PpPDA coatings on protection of steel against corrosion was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), and Atomic force microscopy (AFM) and at various temperatures between 298 and 328 K. Changes in the coating resistance and charge-transfer resistance with temperature were analyzed to determine the activation energies of the processes involved. The determined values of activation energy showed that the EP/PpPDA/SiO2 coating has better anti-corrosion effect than EP/PpPDA. The thermodynamic functions of dissolution processes were also calculated and discussed. The results from AFM observations indicated that the presence of SiO2 nanoparticles increased the roughness of Epoxy-poly p-phenylendiamine/SiO2 nanocomposite (EP/PpPDA/SiO2). It was finally concluded that the presence of silica nanoparticles enhance the protection properties of EP/PpPDA coating as a novel potential corrosion inhibitor for steel. (C) 2014 Elsevier B.V. All rights reserved.