writer：Liang-Qing Zhang, Shu-Gui Yang , Long-Gui Peng, Ke-Peng Zhong and Yan-Hui Chen*
keywords：boron nitride， graphene; polyphenylene sulfide， thermal conductive，electromagnetic interference shielding
source：期刊
specific source：Nanomaterials, 2022, 12(19), 3543.
Issue time：2022年

  The practical application of polymer composites in electronic and communication industry often requires multi-properties, such as high thermal conductivity (TC), efficient electromagnetic interference (EMI) shielding ability with low electrical conductivity, superior tribological performance, reliable thermal stability and excellent mechanical properties. However, the integration of these mutually exclusive properties is still a challenge, ascribed to their different requirement on the incorporated nanofillers, composite microstructure as well as processing process. Herein, a well-designed boron nitride nanosheets (BN)/graphene nanosheets (GNP)/polyphenylene sulfide (PPS) composite with dual segregated structure is fabricated via high-pressure molding. Rather than homogenous mixing of the hybrid fillers, GNP is first coated on PPS particles and followed by encapsulating the conductive GNP layers with insulating BN, forming BN shell-GNP layer-PPS core composite particles. After hot-pressing, dual segregated structure is constructed, in which GNP and BN are distinctly separated arranged in the interfaces of PPS, which on the one hand gives rise to high thermal conductivity, and on the other hand the aggregated BN layer can act as “isolation belt” to effectively reduce the electronic transmission. Impressively, high-pressure is loaded and it has a more profound effect on the EMI shielding and thermal conductive properties of PPS composites with segregated structure than that with homogenous mixed structured composites. Intriguingly, synergetic enhancement effect of BN and GNP on both thermal conductive performance and EMI shielding is stimulated by high-pressure. Consequently, PPS composites with 30 wt% GNP and 10 wt% BN hot-pressed under 600 MPa present the most superior com-prehensive properties with a high TC of 6.4 W/m/K, outstanding EMI SE as high as 70 dB, marvelous tribological performance, reliable thermal stability and satisfactory mechanical properties, which make it promising for application in miniaturized electronic devices in complex environments.