Kinetic stability of toluene-perfluorooctane emulsions

The miscibility of toluene-perfluorooctane-mixtures was investigated and compared to the predictions of some commonly used models. Functional surfactant precursors and nonreacting surfactants were used for emulsifying toluene in perfluorooctane. The effect of surfactant concentration, temperature and volume fraction of toluene on the emulsion stability was studied by measuring the phase volumes and the near infrared backscattering. It was found that toluene and perfluorooctane are completely miscible only at relatively high temperatures and that the common models could not accurately predict the demixing temperatures. The emulsion breakdown and phase separation followed first order kinetics.