INVESTIGATION OF THERMAL PHASE INVERSION IN EMULSIONS

In this paper the phase inversion temperature (PIT) in emulsions was d etermined by measuring the electrical conductivity, dielectric constan t and viscosity. In addition, the detection of the PIT by measuring th e interfacial tension was studied. The temperature-dependent theologic al properties of the emulsions were also examined. The influence of th e oil-phase and emulsifier polarity, the hydrophile-lipophile balances (HLB) value of the surfactant mixture and the phase volume ratio on t he PIT were studied. The phase inversion phenomenon and aspects of per colation theory are discussed. Knowledge of PIT-influencing factors is fundamental for the PIT-type production method of K. Shinoda and H. S aito (J. Colloid Interface Sci., 30 (1969) 258) by which fine disperse d emulsions are produced. Furthermore, the determination of the PIT is important for obtaining optimal storage conditions. The theological m ethod used (coaxial cylinder) as well as the conductivity measurements can be utilized routinely in process production control.