Electrorheological properties of phosphoric ester cellulose electrorheological suspensions at elevated temperatures

The electrorheological (ER) behavior of suspensions in silicone oil of phos phoric ester cellulose powder (average particle size: 17.77 mu m was invest igated at elevated temperatures up to 100 degrees C. For development of anh ydrous ER suspensions for use at wide temperature range, the effect of temp erature on ER activity has studied. Anhydrous ER suspensions were mixed wit h the phosphoric ester cellulose particles made from the phosphoric ester r eactions of cellulose. During increasing temperature, not only analysis of electrical properties, such as dielectric constant, current density and ele ctrical conductivity but also rheological properties of ER suspensions were studied. Current density, conductivity and electrorheological effect (tau( A)/tau(0)) of phosphoric ester cellulose ER suspensions showed law dependen ce on temperature. Shear stress was closely related to the square of dielec tric constant mismatch parameter (beta(2)) under constant shear rate and el ectric field.