Fabrication and Magnetorheological Characteristics of Core–Shell-Typed Poly(2-Methylaniline)/Carbonyl Iron Microspheres

Core–shell particles of the poly-2-methylaniline (PMAN)/carbonyl iron (CI) composite material were prepared by dispersion polymerization. Dopamine was used as a chemical grafting agent to modify the surface of CI particles to enhance the affinity between PMAN particles and pure CI particles. The morphology and crystalline structure of the prepared core–shell PMAN/CI microspheres were tested by TEM and X-ray diffraction, respectively. Their magnetic behaviors were analyzed using a vibrating-sample magnetometer. The sedimentation stability of the particles was further analyzed using a Turbiscan analyzer. The analysis results revealed that the dispersion stability of the particles was better than that of the pure CI particles. The characteristics of the PMAN/CI particle-based magnetorheological fluid with a yield stress of 4800 Pa at 342 kA/m were measured using a rheometer.