Mixed‐surfactant system of dodecylbenzene sulfonate and alpha‐olefin sulfonate: Micellar and volumetric studies

• Published in: Journal of the American Oil Chemists' Society Vol. 73; no. 1; pp. 39 - 45
• Main Authors: Bharadwaj, Satish, Ahluwalia, J. C.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.01.1996; Springer
• Subjects: Alpha‐olefin sulfonate; Chemistry; dodecylbenzene sulfonate; Exact sciences and technology; General and physical chemistry; interaction parameters; mixed micelle; mixed‐surfactant system; partial molar volumes; Surface physical chemistry; Surface-active agents: properties; synergism; Alkali metal Compounds; Monolayer; Molar volume; Binary system; Mixed micelle; Experimental study; Density; Synergism; Sulfonate; Sodium Compounds; Anionic surfactant; Micellar critical concentration; Organic salt; Surface tension; Physicochemical properties
• ISSN: 0003-021X; 1558-9331
• DOI: 10.1007/BF02523446

Critical micelle concentrations of sodium salts of dodecylbenzene sulfonate, alpha‐olefin (C16) sulfonate, and their mixtures have been evaluated by measuring the surface tensions of solutions at 298.15 K. Interaction parameters for mixed monolayer formation (βσ) and mixed‐micelle formation (βM) have been calculated from the critical micelle concentration data. Densities of solutions of surfactants and their mixtures were measured with a vibrating‐tube densimeter at 298.15 K. Apparent and partial molar volumes have been evaluated from solution density data. Results of the micellar properties have been eplained on the basis of a nonideal multicomponent mixed‐micelle model. The mixed‐surfactant system exhibits synergism in all aspects when the mole fraction of alpha‐olefin sulfonate in the mixture is 0.2. Volumetric properties correlate well, as the partial molar volumes also show a minimum at the same composition of the mixture. Formation of a compact mixed micelle at this composition has been envisaged.