▎ 摘　　要

The increasing demand for packaging materials calls for new technologies to achieve excellent thermal conductivity of polymer composites with low content of thermal conductive filler. This article prepared a kind of magnetically functionalized multilayer graphene (Fe3O4@MG) via electrostatic interactions, which efficiently enhanced the thermal conductivity of silicone rubber (SR) composites by the alignment of Fe3O4@MG in an external magnetic field. The morphology and structure of the Fe3O4@MG together with the thermal conductivity of corresponding Fe3O4@MG/SR composites were systematically investigated by SEM, TEM, XRD, elemental mapping, and thermal conductivity tester. The obtained results showed that Fe3O4@MG was induced to form chain-like bundles in silicone rubber matrix under the applied magnetic field, which enhanced the MG-MG interaction, and formed effective thermal pathways in the alignment direction. Furthermore, as coating mass ratio of Fe3O4@MG increased, the thermal conductivity of randomly oriented Fe3O4@MG/silicone rubber composites (R-Fe3O4@MG/SR) decreased gradually, whereas the through-plane thermal conductivity of vertically aligned Fe3O4@MG/silicone rubber composites (V-Fe3O4@MG/SR) increased even filled with same contents of thermal conductive filler. (c) 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47951.