Electrochemical and surface analyses of X70 steel corrosion in simulated acid pickling medium: Effect of poly (N-vinyl imidazole) grafted carboxymethyl chitosan additive
By Eduok, Ubong; Ohaeri, Enyinnaya; Szpunar, Jerzy
Published in Electrochimica Acta
2018
Abstract
In this work, water-soluble poly (N-vinyl imidazole) grafted carboxymethyl chitosan composite (CMCh-g-PVI) has been synthesized from chitosan, characterized and deployed as a corrosion inhibitor for API X70 in 1 M HCl. CMCh-g-PVI composite significantly reduced the corrosion of X70 steel when compared with equimolar concentration of chitosan and carboxymethyl chitosan in the same medium due to the formation of stable protective polymeric films on the metal surface. This was confirmed by means of scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. In depth electrochemical corrosion study was conducted after chloride treatment using potentiodynamic polarization and electrochemical impedance spectroscopic techniques on precleaned substrates. This polymer composite may have a future as an efficient ingredient in corrosion inhibitor formulations for metal surface treatments.