Pickering-Emulsion-Polymerized Polystyrene/Fe2O3 Composite Particles and Their Magnetoresponsive Characteristics

• Published in: Langmuir 2013-04, Vol.29 (16), p.4959-4965
• Main Authors: Kim, Young Jae, Liu, Ying Dan, Seo, Yongsok, Choi, Hyoung Jin
• Format: Article
• Language: English
• Subjects: Chemistry; Colloidal state and disperse state; Emulsions. Microemulsions. Foams; Exact sciences and technology; General and physical chemistry; Physical and chemical studies. Granulometry. Electrokinetic phenomena
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la400523w

Core–shell-structured magnetic polystyrene (PS)/inorganic particles were fabricated by Pickering emulsion polymerization using nanosized Fe2O3 particles as a solid stabilizer. Scanning electron microscopy and transmission electron microscopy confirmed the synthesized PS/Fe2O3 particles to be comprised of a PS surface coated with Fe2O3 nanoparticles. The chemical structure of the composite nanospheres was characterized by Fourier transform infrared spectroscopy and X-ray diffraction. The thermal properties of composite nanospheres and corresponding pure polymer were examined by thermogravimetric analysis. The rheological properties of the core–shell-structured magnetic PS/inorganic particles dispersed in silicone oil were investigated under an external magnetic field strength using a rotational rheometer. The particles with extremely lower density than common magnetic particles exhibited solid-like magnetorheological phase characteristics, and the flow curves were fitted to the Cho–Choi–Jhon model of the rheological equation of state.