A novel class of quaternary ammonium-based
cationic surfactants is synthesized and characterized via
spectroscopic methods (FTIR,
1
HNMR and13
C NMR).
The surface properties, foaming power and biodegrad-ability of the synthesized cationic surfactants are deter-mined using the surface tension technique. The
protection performance with their adsorption mecha-nisms for carbon steel is evaluated in a 15% HCl solu-tion by a series of techniques including electrochemical
impedance spectroscopy, potentiodynamic polarization
curves, scanning electron microscopy (SEM), X-ray
spectroscopy, and UV–visible spectroscopy. The surfac-tants are found to be excellent corrosion inhibitors for
carbon steel. The results show that the inhibition effi-ciencies are increased by increasing the concentration
and the hydrophobic chain length of the tested com-pounds reaching the maximum at 250 ppm. The poten-tiodynamic polarization curves suggested that the
inhibitors behave as a mixed type with predominant
cathodic inhibition and the corrosion behavior can be
explained by the adsorption film mechanism. Moreover,
the mode of adsorption obeys the Langmuir adsorption