THEORETICAL EVALUATION OF CORROSION INHIBITION PERFORMANCE OF ISOXAZOLIDINES DERIVATIVES

The corrosion resisting property of four corrosion inhibitors in HC1 on mild steel,including 2-methyl-5-hexylisoxazolidine(A),2-methyl-5-dodecylisoxazolidine(B),2-isopropyl-5-dodecylisoxazolidine(C) and 2-tert-butyl-5-dodecylisoxazolidine(D),was theoretically evaluated using quantum chemistry calculations and molecular dynamics simulations.The corrosion inhibition mechanism was analyzed.The quantum chemical calculations indicated that the frontier orbitals of four molecules were located in the isoxazole ring and side chain of the molecules.The electrophilic attack centers of the inhibitors were on the N and O atoms.Molecular dynamics calculation shows that under liquid conditions the polarity head group of isoxazolidine corrosion inhibitors priority adsorbed in the metal surface,while the alkyl chain stayed in the water phase with distortion. The strength of molecules adsorbed on the surface enhanced with increasing the number of methyl in the molecular heads.The theoretical evaluation was shown to be in complete accord with experiment results.