The cetyltrimethylammonium bromide-hexanol-water system

An investigation has been carried out of the phase equilibria in the three-component system cetyltrimethylammonium bromide-hexanol-water at 25°C. Separation of the phases was effected by centrifugation and the composition of them was determined by analysis and their internal structure by X-ray diffraction measurements. Their consistency and gross appearance were examined and their texture was observed under the polarizing microscope. The investigation disclosed besides crystalline cetyltrimethylammonium bromide two homogeneous solution phases, the aqueous solution, L 1, and the hexanolic solution, L 2, and two homogeneous mesomorphous phases with different internal structure. One of the mesophases displayed a lamellar structure and the other a two-dimensional hexagonal structure. The vertices of the three-phase triangles and the direction of the tie-lines in the two-phase zones between the regions with homogeneous phases have been determined.