▎ 摘　　要

Here, Ni@graphene nanoplatelet (GNP) nanohybrids are obtained via an interfacial reaction growth method and a series of poly(methyl methacrylate) (PMMA)/Ni@GNP composites are prepared by a solution mixing-ultrasonic dispersion-hot pressing technology. The influence of Ni@GNP on the electromagnetic interference (EMI) shielding, dielectric, and thermal management behaviors of the composites is intensively investigated. The microcapacitors formed using Ni@GNP as plates and PMMA as matrix significantly improve the dielectric properties of the composites. Enhancement on thermal conduction and EMI properties of PMMA composites with increasing Ni@GNP content can be ascribed to the unique structure of Ni@GNP and it is the filler interconnection network that renders the composite's desirable thermally conductive and thermomechanical properties. A facile way of fabricating polymeric composites with satisfactory thermal conductivity and high-performance electromagnetic shielding is provided here. The obtained polymer composites display highly promising applications in the thermal management and EMI shielding of electronic devices.