| Polystyrene (PS)/Fe3O4 nanocomposites with various Fe3O4 particle loadings were synthesized by a solvent extraction method. The dispersion of Fe3O4 nanoparticles (NPs) and the morphology of the PS/Fe3O4 nanocomposites were characterized by the scanning electron microscope (SEM). The effects of the Fe3O4 NPs on the crystallization of PS were also studied by X-ray diffraction (XRD). Fourier transform infrared (FT-IR) spectroscopy analysis indicated a physical entanglement rather than chemical bonding between the NPs and the PS matrix. The thermal properties of the PS/Fe3O 4 nanocomposites were characterized by a thermogravimetic analyzer (TGA) and differential scanning calorimeter (DSC). High thermal stability was observed after introducing the nanoparticles into the polymer matrix. The effects of nanoparticle loading and temperature on the storage/loss modulus of the PS/Fe 3O4 nanocomposites were studied systematically. The mechanical, magnetic, dielectric, and flame retardant properties were studied as well. The glass transition temperature (Tg) of the PS/Fe3O4 nanocomposites has shifted to the higher temperature in the dynamic mechanical analysis (DMA) compared with that of the pure PS. Enhanced dielectric and flame retardant properties of the PS/Fe3O4 nanocomposites were related to the Fe3O4 nanoparticle loadings. The PS/Fe3O4 PNCs exhibit superparamagnetic behavior at room temperature. |
