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.

A nanocolloidal dispersion of lead chromate (PbCrO4) has been prepared in H2O/sodium bis(2-ethylhexyl)sulfosuccinate (AOT)/n-heptane water-in-oil (w/o) microemulsion medium. The formation of the PbCrO4 in the water pool of the microemulsion has been established by Fourier transform infrared measurements. The absorbance and fluorescence behaviors of the colloidal PbCrO4 have been investigated with varying water pool size, i.e., varying [water]/[AOT] mole ratio, ω. The dimension of the lead chromate encapsulated microemulsion droplets has also been determined by the dynamic light scattering method under varied ω. The dimension and shape of the colloidal dispersions in microemulsion have been examined by transmission and scanning electron microscopic measurements.

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