Interaction and Properties of the Synthesized Anionic Surfactant with CTAB: An Experimental and Theoretical Investigation

Abstract Anionic surfactant salt‐type fatty alcohol ether carboxylic ester (AEC 5 E−Na) having poly(oxyethylene) group was synthesized with a green and efficient method, and the structure of it was characterized by Fourier Transform Infrared Spectroscopy (FT‐IR), 1 H‐Nuclear Magnetic Resonance ( 1 HNMR) as well as Matrix‐assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI‐TOF‐MS). The interactions between AEC 5 E−Na and cationic surfactant hexadecyl trimethyl ammonium bromide (CTAB) were elucidated based on the Rubingh's theory by comparing the actual and ideal values of critical micelle concentration (cmc), maximum surface excess concentrations (Γ max ) and minimum surface area of per surfactant molecule (A min ). In addition, the compositions, interaction parameters and activity coefficients for surfactant mixtures AEC 5 E−Na/CTAB in the micelles and at the interfaces were evaluated. It has been observed that there is a synergism in the surfactant mixtures AEC 5 E−Na/CTAB. Moreover, synergism is also manifested in the contact angle, dynamic surface tension, wetting, emulsification and foam stability. The thermodynamics results of the micelles demonstrated that the formation of micelles in the binary mixtures is a process of enthalpy‐drive and exothermic.