Abstract
In this report, novel series of unsaturated polyesters Va-d and VIa-d containing indazole moiety were successfully prepared via interfacial polycondensation technique of indazole derivatives III and IV with different aromatic and aliphatic acid chlorides; isophthaloyl-, terephthaloyl-, adipoyl-, and sebacoyl chlorides. The prepared polyesters were categorized by elemental analyses, IR, H-1 NMR, Mass spectra, GPC, Thermogravimetric (TGA), X-ray analyses (XRD), and therefore the morphology was examined by scanning microscopy (SEM). They showed high thermal stability and different morphology structure. The corrosion protection performance of prepared polyesters Va-d and VIa-d on X65-steel in molar oil of vitriol was assessed using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), and SEM. Electrochemical tests (EIS and PDP) displayed polymers could efficiently impede the X65-steel corrosion and acted as inhibitors of the mixed type. At the optimal dose of 150 mg/L, the protection capacities of Va-d and VIa-d polymers ranged from 86.9% to 97.8%. adsorption of Va-d and VIa-d followed the adsorption model of Langmuir isotherm. Surface morphology examination by SEM also revealed that Va-d and VIa-d polymers form an efficient block layer on the surface of X65-steel to separate the acidic solution.