THE ELECTRORHEOLOGICAL PROPERTIES OF POLYANILINE SUSPENSIONS

The electrorheological properties of suspensions containing polyaniline particles in silicon oil are reported for a range of suspension volume fractions, applied field strengths, shear stresses, and particle dielectric constants. Suspension viscosity at a fixed stress is found to increase slowly as the field strength is raised to a value of E*. Over a very narrow field strength range near E* the suspension viscosity is found to increase 106-108 Pa s. At field strengths greater than E*, the suspensions take on solid-like behavior. The scaling of yield stress on volume fraction and field strength is similar to that reported on other systems and the yield stress is found to increase monotonically with particle dielectric constant. © 1990.