Anticorrosion coatings based on epoxy ester containing different concentrations of dodecyl benzene sulfonic acid doped polyaniline nanoparticles (nPAni(DBSA)) were prepared and applied on the carbon steel surface. The corrosion behavior of this system in saline-alkaline solution (3.5% NaCl and pH 9) was studied using electrochemical impedance spectroscopy (EIS) during 100 days immersion. At the end of immersion, the metal/coating interface was analyzed using scanning electron microscopy (SEM) and Raman spectroscopy. The obtained results showed that nPAni(DBSA) particles could efficiently improve the anticorrosion performance of the epoxy ester coating through both the barrier and the active mechanisms where the best corrosion inhibition of carbon steel was attained at 1.5% of nPAni(DBSA). The active inhibition of nPAni(DBSA) is attributed to the formation of a secondary passive layer at the metal/coating interface.

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