| 초록 |
Magnetorheological (MR) fluids have been considered as one of the smart materials because of their controllable characteristics with external magnetic field. Since their first discovery, there have been a lot of studies on MR characteristics and their applications. However, the MR fluids have an issue with sedimentation of suspended particles due to mismatch to the MR fluids for the industrial applications. Nano-sized PMMA and PS particles were adopted to prevent the sedimentation problem via being dispersed between the micron-sized CI spheres. For purifying the dispersant, both PMMA and PS were synthesized by soap free emulsion polymerization. The weight fraction of polymer particles in suspensions was fixed to 0.1 ~ 1%. Physical morphology of the nano-sized PMMA and PS particles was confirmed via SEM images. Stability of sedimentation was observed by turbiscan. Rheological properties of the MR suspensions were observed via a rotational rheometer. |
