Abstract: Comparison of azo polyesters and their monomer precursors on corrosion of mild steel in acid medium has been studied by electrochemical and non-electrochemical techniques. The result of the study revealed that the inhibition efficiency of the polyesters vary with concentration and temperature. Values of activation energy of inhibited solution were greater than the value obtained for blank. Thermodynamic consideration revealed that the adsorption of polyesters on mild steel surface was spontaneous and occurred according to Langmuir adsorption isotherm. Physical adsorption mechanism has been proposed for the adsorption of the inhibitors. Polarization data indicated that the polyesters behave as mixed type inhibitors but slightly cathodic in nature. The synergistic influence of halide ions and CTAB has been evaluated by weight loss method. The surface morphology of mild steel specimen was evaluated using optical microscope.

 

Keywords: Corrosion, Inhibitors, Polyesters, CTAB, Optical microscope.