Cationic Surfactants in Organic Solvents III. Critical Micelle Concentration of Dodecylammonium Halides in Benzene and Toluene

The behavior of pr imary, secondary, tert iary and quaternary dodecylammonium chloride and bromide in benzene and toluene was investigated by surface tension measurements , the dye-solubilizafion and iodine-complex formation method and vapor pressure osmometry a t 37 ° and 50°C. The smooth cont inui ty in the measured properties of these solutions as a function of concentration has been interpreted in terms of a progressive oligomerization of the cationic surfactants rather than in terms of a monomer --~ micelle equilibrium, familiar in aqueous solutions. No indication for the phenomenon of critical micelle concentration could be observed.