Electrical Behaviour of Non-Aqueous Disperse Systems

Abstract

THE electrical conductivity of dispersions of conductive powders increases with time of rest after shear according to the expression: , where n is an exponent between unity and 1.5, and K is equal to when time is unity. The instantaneous conductivity, however, at any given state of rest after shear increases with increase in the A.C. or D.C. potential applied, attaining an asymptotic value at an E.M.F. depending on the composition of the material. Measurement of specific inductive capacity of flocculated dispersions on an A.C. bridge presents great difficulties owing to the time involved in securing a balance and the constant growth of conductivity due to thixotropic effect. Nevertheless, indications are shown of specific inductive capacities of the order of thousands when measured at 50 cycles, down to tens at 300,000 cycles.