Construction of brick/mortar-like graphene/thermoset composites with highly anisotropic thermal conductivity and strong electromagnetic interference shielding performance

The increasing demand for integrated and miniaturized electronic components requires the simplified production of high-performance and versatile nanocomposites. Herein a novel approach for obtaining graphene/thermoset composites with switchable properties was proposed via smart structural rearrangement of graphene/thermosetting resin hybrids. Specifically, highly oriented layered graphene composite sheets were successfully constructed by using the vacuum-assisted self-assembly method. Besides, an amide and furan functional benzoxazine resin was synthesized and used as an interlayer adhesive for consolidating the brick/mortar-like graphene/thermoset composites. The additional thermal treatment facilitated the chemical conversion of polybenzoxazine into polybenzoxazole networks, which significantly enhances the interface interaction between the polymeric matrix and graphene nanosheets. Notably, the newly obtained brick/mortar-like graphene/thermoset composites showed exceptionally high thermal conductivity (47.8 W m-1 K-1), remarkable toughness, and outstanding electromagnetic shielding effectiveness (48.4 dB), suggesting their high potential applications in the fields of electronics, military, and aerospace. A new fabricating strategy has been successfully employed to prepare brick/mortar-like graphene/thermoset composites with highly anisotropic thermal conductivity and excellent electromagnetic interference shielding performance.