Electrorheological properties of anisotropically filled elastomers

We report the results of numerical simulations for the change of both mechanical and electrical properties of elastomers with anisotropically filled polarizable particles under capacitively graded electric and mechanical fields. Such composites have potential applications in electromechanical control. We have used numerical techniques to study the effect of particle shape, permittivity/conductivity ratio, and spatial arrangement on the shear modulus as a function of the electric field. We also investigated the influence of the high field and nonlinear conductivity in the polymer matrix. The results indicate that electrostatic energy and changes therein, which result in electro-rheological effects, are concentrated between particles, and that the electrostatic interaction between the particles is concentrated in a very narrow regime at the tip of the particles, The interaction increases with the electric field intensity until the field between the particles is high enough to cause nonlinear electrical conduction in the polymer, resulting in a redistribution of the electric field and electrostatic energy