Physicochemical Studies on Microemulsions. 6. Phase Behavior, Dynamics of Percolation, and Energetics of Droplet Clustering in Water/AOT/n-Heptane System Influenced by Additives (Sodium Cholate and Sodium Salicylate)

The phase behavior as well as the volume- and temperature-induced percolation of a water in oil (w/o) microemulsion system of water/AOT/ n -heptane have been studied in detail in the absence and presence of additives, sodium cholate (NaC) and sodium salicylate (NaS). The results have been examined in light of the appropriate scaling equations. The scaling parameters have been observed to be not in agreement with the predicted values. The energetics of droplet clustering leading to percolation have been also estimated. The amphiphile-coated size of the water nanodroplets and their diffusion coefficient and polydispersity have been estimated in the pre- and postpercolation stages. Rationalization of the results has been attempted.