Synthesis of 1,3-bis-[(dodecanoyl oxypropyl dimethylammonium) propanel dibromide ester-quat surfactant: Micellar, thermodynamic and corrosion-inhibiting properties

Ester-quat surfactant: 1,3-bis-[(dodecanoyl oxypropyl dimethylammonium) propane] dibromide referred as 12-3-3-3-12 was synthesized, purified and characterized by Elemental Analysis, H-1-NMR, C-13-NMR, IR and Mass Spectra. The thermodynamic properties of aqueous solutions of this ester-quat were investigated using Electrical Conductivity and SurfaceTension measurements. The corresponding parameters of micellisation were determined for each technique. otherwise the inhibitive action of the ester-quat (12-3-3-3-12) on the corrosion behaviour of iron was investigated in HCl and H2SO4 medium by means Electrochemical Resistance and Polarisation methods. The ester-quat 12-3-3-3-12 acts as a cathodic-type inhibitor. The maximum inhibition efficiency was reached around the critical micellar concentration. The ester-quat appears to be adsorbed in the metal/ liquid interface through the general mode following the Frumkin adsorption model.