Dielectric Constants of Emulsions

in-oil (W/0), and nitrobenzene-in-water (N/W) emulsions at rest and under shear were measured over a wide range of concentration and at frequencies ranging from 20 cps. to 5 mc. The 0/W emulsions showed neither dielectric dispersion due to the interfacial polarization nor influence of shearing flow on dielectric properties, the concentra-tion dependence of their dielectric constants and conductivities being expressed best by the equations of the Bruggeman type. In the case of W/0 emulsions, striking dielectric dispersions due to the interfacial polarization were observed at high frequency range above 100 kc. Both the limiting dielectric constants at low frequencies and the conductivities at high frequencies decreased with increasing rate of shear. These shearing effects may he attributable to the breaking up of particle agglomerates, The limiting dielectric constants at high frequencies were subjected to no shearing effect, being expressed best by the Bruggeman equation. The N/W emulsions, which are a kind of 0/W emulsions, showed dielectri