tEpoxy-poly p-phenylendiamine (EP/PpPDA) and its nanocomposite with SiO2nanoparticles(EP/PpPDA/SiO2) were synthesized and tested as potential corrosion inhibitors of steel in 1 M HClsolution. Performance of EP/PpPDA/SiO2and EP/PpPDA coatings on protection of steel against corrosionwas investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS),and Atomic force microscopy (AFM) and at various temperatures between 298 and 328 K. Changes inthe coating resistance and charge-transfer resistance with temperature were analyzed to determine theactivation energies of the processes involved. The determined values of activation energy showed that theEP/PpPDA/SiO2coating has better anti-corrosion effect than EP/PpPDA. The thermodynamic functions ofdissolution processes were also calculated and discussed. The results from AFM observations indicatedthat the presence of SiO2nanoparticles increased the roughness of Epoxy-poly p-phenylendiamine/SiO2nanocomposite (EP/PpPDA/SiO2). It was finally concluded that the presence of silica nanoparticlesenhance the protection properties of EP/PpPDA coating as a novel potential corrosion inhibitor for steel.
