Synthesis and Surface Active Properties of a Novel Linear Dodecyl Diphenyl Ether Sulfonate Gemini Surfactant

摘要

The linear dodecyl diphenyl ether sulfonate gemini surfactant (C12-DLADS) has been synthesized by a new route from lauric acid according to a five-step reaction sequence consisting of acidification, Friedel–Crafts acylation, Clemmensen reduction, sulfonation and a neutralization reaction. The surfactant and intermediates were characterized by 1H-NMR, HPLC/MS and elemental analysis. The properties have been studied by surface tension (γ CMC) and conductivity measurements. The thermodynamic parameters of micellization were calculated. The test results show that C12-DLADS has lower critical micelle concentration (CMC) and better capability for lowering the γ CMC. The γ CMC and CMC are 36.04 mN/m and 6.03 × 10−4 mol/L respectively at 45 °C. Moreover, with the increase in temperature, the conductivity of C12-DLADS increased, while the counterion binding K 0 decreased. The thermodynamic data show that the micellization process for the surfactant C12-DLADS is entropy driven.