Electrorheological effect in immiscible polymer blends

A new model of the electrorheological (ER) effect for immiscible polymer blends is' proposed on the basis of microscopic observations. In the absence of an electric field the polymer with high viscosity is dispersed as droplets in the other polymer with low viscosity, while in the presence of an electric field, the droplets stretch and coalesce to form bridges between electrodes, resulting in the increase of the macroscopic viscosity. A few experimental results are given to confirm the validity of this model. (C) 1997 The Society of Rheology.