FACTORS INFLUENCING THE SOLUBILIZATION CAPACITY OF WATER/OIL MICROEMULSIONS / FACTEURS INFLUENÇANT LA CAPACITÉ DE SOLUBILISATION DES MICROÉMULSIONS EAU/HUILE

Abstract

The solubilization capacity of water / oil / AOT (sodium bis(2 ethylhexyl)sulfosuccinate) microemulsions was studied as a function of a fourth component added in the system. Addition of cosurfactant modifies the water solubility and the properties of the system. The influence of some alcohols with linear and branched hydrocarbon chains and a cationic hydrosoluble dye, methylene blue (MB), on the solubilization of water in water/oil microemulsions was studied. The value of the molar ratio of water to surfactant, R, increases in the alcohols presence as the volume of solubilized water was increased. The increasing of R leads also to a significant increase of the radius of water-core of the droplets in microemulsion. A separation of water in w/o microemulsion appears when concentration of alcohol is 9×10-4 M and the volume of water increases, becoming 1.2 to 2.5 times higher if the concentration of alcohol rises to 1.2×10-3 M. Addition of MB into microemulsion leads to the doubling of the volume of separated water. The partition of MB between microemulsion and water phases shows that the dye migrates preferentially in the microemulsion phase in the presence of alcohols.

Keywords

• AOT
• methylene blue
• micro emulsion
• solubilization