Dielectric and rheological, behaviors of semiconductive polymer suspensionas an electrorheological fluid

We have studied the dielectric and rheological characteristics of semicondu ctive polymer based ER fluids. Under static electric field, yield stress of suspension was found to be closely related to the dielectric properties: t hat is in accord with the Maxwell-Wagner interfacial polarization. The diel ectric constant showed maximum then decreased with increasing bulk conducti vity of particle as the yield stress behaviors did. Particle-medium interac tion on ER response was also examined by utilizing appropriate surfactant. These experimental results were consistent with the prediction based on the recent model studies. Over wide range of temperature, our ER fluid maintai ns its activity so that it can broaden the potential applicability as a sma rt material.