Effects of High Electric Fields on Dielectric Liquids of High and Low Viscosity

When a portion of a liquid dielectric was subjected to an electric dc field of high intensity, the level rose locally. The maximum rise attained by different liquids above the liquid level outside the field increased with their dielectric constant and polarizability. The following observations indicate that electrostriction rather than electrophoresis was the cause of the observed rise in liquid level. (a) Molten polymers, which have such high viscosities that electrophoretic motion of ions or charged particles is virtually suppressed, rose to the same heights as fluid liquids. (b) Neither inverting the direction of the field nor (c) adding 0.05% finely dispersed aluminum or 0.15% ultramarine powder to molten polyethylene affected the rise in the dc field qualitatively or quantitatively. Repulsion occurred in very high fields, producing a slight depression in the liquid level.