Abstract:
Monooctadecyl maleate was synthesized by the mono-esterification of maleic anhydride and octadecanol, and used to surface-modify Fe3O4 nanoparticles as a polymerizable surfactant. Polymerizable magnetic fluid was obtained by dispersing Fe3O4 nanoparticles into styrene monomer with ultrasonic wave and PSt-Fe3O4 magnetic nanocomposite was prepared through free radical polymerization. The structure, crystallization status and dispersion status in different dispersion phases of modified Fe3O4 nanoparticles were studied by FT-IR, XRD and TEM. Results show that the Fe3O4 nanoparticles modified by monooctadecyl maleate with the size of about 8-12 nm are of typical Fe3O4 cubic spinel structure and can be uniformly dispersed into styrene and fixed in nanocomposite during the polymerization. Results of TGA and Vibrating Sample Magnetometry (VSM) indicate that the prepared PSt-Fe3O4 nanocomposites are superparamagnetic and show the improved thermal stability compared with polystyrene under the same polymerization condition.