Thermodynamic and Electrochemical Investigations of Poly(Methyl Methacrylate–Maleic Anhydride) as Corrosion Inhibitors for Mild Steel in 0.5 M HCl

Abstract

In this research, poly(methyl methacrylate-maleic anhydride)P(MMA-MAH)s with different percentages methyl methacrylate and maleic anhydride were synthesized and studied. Then the inhibitory potential of these copolymers on simple carbon steel in a 0.5 M HCl environment was investigated. Electrochemistry techniques have investigated the inhibitory potential of P(MMA-MAH)s in different concentrations at 25°C. Electrochemical investigations show that these copolymers with different percentages of mixed inhibitors has the inhibitory superiority of anodes over cathodes. Also, the adsorption of these polymers onto plain carbon steel follows the Langmuir adsorption isotherm. Field emission scanning electron microscopy (FE-SEM), X-ray energy dispersive spectroscopy (EDX) were employed to confirm the results of the potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The results of this study showed that P(MMA 30 mol %-MAH 70 mol %) had the highest corrosion resistance, followed by P(MMA 50 mol %-MAH 50 mol %) and P(MMA 70 mol %-MAH 30 mol %).