| 초록 |
A custom designed vertical oscillation rheometer (VOR) is used for the rheological measurements of electrorheological (ER) fluids consisting of 20 wt% cellulose particle suspended in silicone oil. The viscoelastic material functions, including complex viscosity and complex shear modulus, are measured via geometric parameters, measured force, and applied strain of the VOR. Viscoelastic properties of the ER fluids are also measured as a function of applied electric field strength and particle concentration [1, 2]. The VOR, equipped with a high voltage generator, can easily be constructed and used to measure ER properties. It was found that in linear viscoelastic conditions, elasticity was promoted with the increment of electric field due to particle chain structure in the presence of the applied electric field. [1] Langmuir 19, 5875 (2003) [2] J. Appl. Polym. Sci. 79, 108 (2001). |
