Micellar behavior of tetradecyldimethylbenzylammonium chloride in water-alcohol mixtures.

The effect of butanol and benzyl alcohol on the critical micelle concentration and the degree of ionization of micelles of tetradecyldimethylbenzylammonium chloride has been studied conductometrically in the temperature range of 5 to 40 degrees C at 5 degrees C intervals. The results indicate that some self-association process of benzyl alcohol in the aqueous phase commences when its concentration amounts to ca 0.05 m. By applying the theoretical treatment suggested by Motomura for binary surfactant systems, the molar fraction of alcohol in the micelle and the standard free energy of solubilization were estimated from the dependence of cmc on temperature and alcohol concentration. For comparative purposes the micellar properties of tetradecyltrimethylammonium bromide in water-alcohol systems at 25 degrees C have also been studied.