Micellar interactions in water-in-oil microemulsions. 2. Light scattering determination of the second virial coefficient

Both the intensity and the autocorrelation function of the light scattered by water-in-oil (W/O) microemulsions have been studied. The investigated microemulsions were formed from water, dodecane, sodium dodecyl sulfate, and pentanol or hexanol or heptanol. Micellar size and virial coefficients were extracted from experimental data. The data evidence that interactions in these systems mainly depend on alcohol chain length. They are strongly attractive in microemulsions containing pentanol and much less in hexanol and heptanol systems. The intermicellar potential presented in paper 1 allows one to interpret the scattering results and provides an approach for the understanding of the variations of the B values; the agreement between theory and experiment is very good.