Adsorption and Surface Properties of Mixtures of Fatty Acid Methyl Ester Ethoxylates and Sodium Dodecylbenzene Sulfonate

摘要

Adsorption behavior of mixtures of fatty acid methyl ester ethoxylates (FMEE) and sodium dodecylbenzene sulfonate (LAS) was studied and the adsorption parameters were calculated. The critical micelle concentration (CMC) and surface tension were measured by Wilhelmy plate method. Physicochemical properties of the mixtures were also investigated, such as cloud point and foaming property. The results show that the CMC of LAS was much higher than that of FMEE and decreased significantly by adding a low quantity of FMEE, while a powerful interaction between FMEE and LAS molecules in the micelles and the surface adsorption layer was exhibited. The cloud point and foaming property of the mixtures increased with increasing LAS content. An obvious change of the physical form of LAS solution by adding FMEE was observed.