The electrochemical behavior and anticorrosion properties of modified carbon black (CB) nanoparticles in epoxy coatings were investigated in accelerated conditions. Nanoparticles of CB were modified by sodium dodecyl sulfate (SDS) as surfactant. Dispersion of nanoparticles into epoxy was confirmed by Transmission Electron Microscopy (TEM). The accelerated condition was prepared at 65 degrees C. CB nanoparticles improved corrosion resistance of the epoxy coating. The optimum concentration of CB in the epoxy coating was 0.75 wt%. Results showed that the CB hinder the corrosion due to its barrier properties. CB can decrease the diffusion coefficient of water in the coating with filling the micropores. (C) 2015 Elsevier B.V. All rights reserved.