A dielectric study of the monothermal freezing of supercooled water dispersed within emulsions: a preliminary report

The dielectric properties of emulsions of supercooled water in blends of lanolin and Vaseline oil have been investigated in the frequency range 0.1 kHz-3 MHz. Preserved at subzero temperatures higher than about -15 degrees C, the emulsions exhibit a Debye-type relaxation that remains unchanged for at least a few months. At preservation temperatures lower than -15 degrees C but higher than about -40 degrees C the above mentioned dielectric relaxation evolves towards a relaxation of the same type, but similar to that related to ice dispersions in oil. This evolution, resulting from the progressive freezing of the population of droplets, can be described by means of a theoretical model based on the population of droplets, can be described by means of a theoretical model based on a computerized numerical analysis of Hanai's formula (1968). Thus, it is possible to show that the distribution in time of the freezing of the supercooled water droplets dispersed within an emulsion is of the gaussian type.