ENHANCED ELECTRORHEOLOGICAL FLUIDS USING ANISOTROPIC PARTICLES

The electrorheological (ER) phenomenon is widely attributed to the cha ining of micron-sized polarizable particles when subjected to an exter nal electric field. It has been hypothesized that the strength of the particle-particle interactions determines the rheological properties o f ER fluids. On the basis of an electrostatic polarization model, we p roposed that by controlling the geometry of the particles, the dielect ric properties of ER fluid can be enhanced, resulting in increased str ength of the particle-particle interactions. In this work, we have dev eloped systems featuring anisotropic particles and conducted a systema tic study of the role of particle geometry in the response of ER fluid s. Our findings appear to be in agreement with the electrostatic polar ization model. (C) 1998 The Society of Rheology.