Constructing hierarchical polymer@MoS2 core-shell structures for regulating thermal and fire safety properties of polystyrene nanocomposites

Two dimensional MoS2 acting as reinforcing fillers had attracted intense interests in recent years. However, the homogeneous dispersion of MoS2 nanosheets in polymer matrix and exact interface control were still difficult to achieve due to potent van der Waals forces and surface inactiveness. In this work, hierarchical polystyrene@MoS2 core-shell structures were constructed by combining latex technology and self-assembly of oppositely charged MoS2 nanosheets onto the surface of polystyrene spheres. The formed core-shell structures were characterized by X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy, transmission electron microscopy and further employed as reinforcing fillers in a host polystyrene matrix by solvent blending method. It was clearly observed that the construction of polystyrene@MoS2 core-shell structures not only improved the dispersion of MoS2 in the matrix and the interfacial adhesion between MoS2 and polystyrene, but also obviously improved the thermal stability and fire safety of polystyrene. The method proposed here had proved to be an efficient and facile approach to fabricate polymer/MoS2 nanocomposites with good dispersion and markedly improved properties.