Electrorheological characteristics of phosphate cellulose-based suspensions

As a potential candidate for the development of anhydrous electrorheologica l (ER) materials, phosphate cellulose particles were synthesized from a pho sphoric ester reaction between cellulose particles and a 2 M phosphoric aci d-urea mixture, and then dispersed in silicone oil to prepare the phosphate cellulose-based ER fluid. Rheological measurements were carried out via a rotational rheometer with a high voltage generator in both steady and oscil latory shear modes to investigate the effects of electric field strength an d particle concentration on ER performance. The results show not only that the ER properties are enhanced by increasing the particle concentration and electric field strength, but also the cellulose-based ER fluids exhibit vi scoelastic behavior under an applied electric field due to the chain format ion induced by electric polarization between particles. (C) 2001 Published by Elsevier Science Ltd.