The critical micelle concentrations (CMC) and the counter ion binding constants (B) in a micellar state of the mixed surfactant systems of sodium dodecylbenzenesulfonate (DBS) with polyoxyethylene(4) lauryl ether (Brij 30) in water were determined as ...
The critical micelle concentrations (CMC) and the counter ion binding constants (B) in a micellar state of the mixed surfactant systems of sodium dodecylbenzenesulfonate (DBS) with polyoxyethylene(4) lauryl ether (Brij 30) in water were determined as a function of 1 (the overall mole fraction of DBS) by the use of electric conductivity method and surface tensiometer method from 288 K to 308 K. Various thermodynamic parameters (Smo, Hmo, and Gmo) for the micellization of DBS/Brij 30 mixtures were calculated and analyzed from the temperature dependence of CMC values. The measured values of Gomare all negative but the values of Smo are positive in the whole measured temperature region. On the other hand, the values of Hmo are positive or negative, depending on the measured temperature and 1.