Emulsions as materials with adjustable dielectric properties

Emulsions are examined as materials with adjustable electrical properties (relative permittivity and conductivity). The emulsions are simple mixtures of oil, saline solution, and a stabilizing agent (emulsifier). The relative permittivity of oil is around two, while that of water is around 80. Thus, a wide range of relative permittivity can be obtained by mixing these components. The conductivity of the emulsion can be adjusted by changing the concentration of the electrolyte, sodium chloride, in the aqueous phase. Bruggeman´s theoretical formula for the electrical constitutive parameters of a heterogeneous system is applied to the emulsions. A series of oil-in-water emulsions has been formulated for use in scale models; this involves the selection of an appropriate emulsifier. The electrical constitutive parameters of these emulsions are predicted by the simplified Bruggeman´s formula for a wide range of volume fraction of oil and normality of the saline solution.<>