STRUCTURAL STUDY OF BIMETALLIC BIS(2-ETHYLHEXYL) SULFOSUCCINATE AGGREGATES

Bimetallic bis(2-ethylhexyl) sulfosuccinate surfactant is used to form water in oil aggregates. It is shown strong structural changes by increasing the water content. At low water content spherical droplets are observed. By increasing the water content, the cylinder aggregates are formed. The maximum amount of water solubilized using bimetallic surfactants is relatively low (the limit value of the ratio of water over sodium bis(2-ethylhexyl) sulfosuccinate concentration, w, is less than 7 using bimetallic surfactants and is equal to 60 using sodium bis(2-ethylhexyl) sulfosuccinate). At higher water content a phase transition is observed with two isotropic phases, with the lower phase containing mainly the surfactant. Using mixed micelles (bimetallic and sodium bis(2-ethylhexyl) sulfosuccinate surfactants), the limit of w increases and spherical droplets are formed at high water content.