Synthesis and characterization of diglycidyl bisphenol A aryl ether sulfone epoxy resin as a corrosion inhibitor for mild steel in 1 M HCl solution: DFT, MC, and MD studies

In this study, we prepared an epoxy resin, namely diglycidyl bisphenol A aryl ether sulfone (DGBAAES). The chemical structure of this inhibitory resin (DGBAAES) was confirmed by spectroscopic techniques, namely proton and carbon nuclear magnetic resonance (¹H-NMR, ¹³C-NMR), as well as infrared spectroscopy (FT-IR). DGBAAES inhibitory resin was assessed its ability as an effective agent to protect the mild steel (MS) in 1 M HCl environment, including experimental (PDP and EIS) and theoretical approaches (DFT, MC and MD simulations). The inhibitory performance of DGBAAES was found to be enhanced based on the results of the electrochemical tests. The results demonstrated that at an ambient temperature of 298 K, 10⁻³ M of DGBAAES exhibited a protection level of 95.2%. The polarization curve affirmed that DGBAAES acted as a mixed-type inhibitor, effectively impeding both anodic and cathodic reactions on mild steel. According to the Langmuir model, DGBAAES formed a defending deposit on the surface of metal. SEM, EDS, and CA characterization revealed a significant difference in MS area owing to the protective barrier formed on used substrates.