| 초록 |
Electrorheological (ER) fluid is a smart material whose rheological properties including yield stress, shear viscosity and shear modulus, can be dramatically and reversibly changed by external electric fields. It was recently reported that one dimensional polyaniline (PANI) fiber had better ER response and reduced sedimentation than normal PANI particles. Therefore, in this study, we fabricated PANI fibers via an interfacial polymerization process. The fibers were washed and re-dispersed in ethanol/water solution together with tetraethyl orthosilicate (TEOS) and hydrous ammonia. Flow curves of pure PANI fiber and silica modified PANI fiber based ER fluids in silicone oil were tested by a rotational rheometer (MC 120) . The special flow curves were fitted very well by our suggested Cho-Choi-Jhon (CCJ) model. Dielectric analysis, observed by LCR meter supported the ER result very well that higher dielectric constant and shorter relaxation timer are favorable for better ER effect. |
