Three cationic surface active agents were synthesized from the chemical modification of 2-
aminobenzothiazole. The chemical structures of these surfactants were confirmed, IR and 1
H NMR
spectra. The synthesized compound showed high surface activity. The inhibition of the cationic
surfactant on the corrosion of carbon steel in acidic media of 1 M HCl was studied by weight loss
measurements, potentiodynamic and electrochemical impedance spectroscopy (EIS). The inhibition
efficiency depends on both of concentration and length of hydrophobic chain. The inhibition efficiencies
obtained from the used techniques were in good agreement with each other. The adsorption of the
inhibitors obeyed Langmuir adsorption model. Polarization measurements showed the mixed type
behavior of the synthesized inhibitors, which inhibits the cathodic and anodic parts of the corrosion
reaction in the acidic media