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The present study is focusing on evaluating theoretically and experimentally stability and type of interactions between the epoxy resin bisphenol A diglycidyl ether (DGEBA)‐polyaminoamide anticorrosive coating and high strength low alloy steel surface 15CDV6. The coated steel samples were subjected to a harsh environment of an electrolyte solution of 3 wt % NaCl to simulate the corrosive marine environment. The performance of the epoxy coating was investigated using electrochemical impedance spectroscopy (EIS). The EIS results revealed the occurrence of some deterioration in the film after subjecting it to a harsh environment for 4392 h, because the impedance of the coating dropped by about 1.4 kΩ.cm2. Surface morphological study of metallic specimens before and after exposing to the simulated marine environment (3 wt % NaCl) was carried out using scanning electron microscopy, energy dispersive spectroscopy (EDS), and optical microscope (OM) methods. The interactions between DGEBA‐polyaminoamide and the metallic surface were further carried out using computation modeling such as density functional theory (DFT)‐based quantum chemical calculations, Monte Carlo (MC), and molecular dynamics (MD) simulations. Results showed that DGEBA‐polyaminoamide possesses a strong tendency to adhere and inhibits the corrosive dissolution of 15CDV6 steel surface in the stimulated marine environment. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48402.

This study aims to use the tissues of Cyclamen persicum tubers to prepare activated carbon (CTAC) by different methods then to set up a thermodynamic study of the pharmaceutical diclofenac sodium (DCF) adsorption from aqueous solution onto this activated carbon. Optimum percent of DCF removal was 72% when CTAC dosage was 0.25 g and DCF concentration 50 mg/L. Percentage removal of DCF increases when the concentration of DCF increases as the maximum percentage removal reached 81% when DCF concentration was 70 mg/L and 0.7 g CTAC and pH ranging from 6 to 2.Freundlich model describes efficiently adsorption isotherm of DCF onto CTAC with n equal to 1.398 whose value indicates a favorable adsorption. This finding validates the assumption of multilayer physical adsorption process of DCF. The results showed that DCF was physically adsorbed onto CTAC, as confirmed by the values of DH°minor than 40 kJ/mol. As DG°had negative charge, the adsorption process is exothermic, and the adsorption process of the DCF onto CTAC is spontaneous, depending on temperature. ª 2014 The Authors. Production and hosting by Elsevier B.V. on behalf of University of Bahrain. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

The inhibitive action and adsorption behaviour of pomegranate leave extract (PGLE) on corrosion of carbon steel in 1M HCl solution at 293-333 K was investigated through chemical (weight loss measurements), electrochemical (potentiodynamic polarisation) and surface analysis [Fourier transform infrared (FTIR) and X-ray diffraction (XRD)] methods. Results obtained shows that the adsorption of PGLE molecules on the C steel surface obeyed the Langmuir adsorption isotherm and acts as mixed type inhibitor for C steel in 1M HCl with anodic as its dominant inhibitor at high concentration. The inhibitory property of the extract was discussed in terms of the mechanism by which its components adsorb onto the C steel surface. Activation energy of corrosion and other thermodynamic parameters such as standard free energy, standard enthalpy and standard entropy of the adsorption process as well as FTIR and XRD examinations of the electrode surface revealed that the corrosion inhibition of C steel in 1M HCl in the presence of PGLE is mainly controlled by the physical adsorption process.