▎ 摘　　要

How to prepare high thermal conductive epoxy composites is still a challenge. In this work, polyethylene glycol (PEG) is introduced to the interface of liquid crystalline epoxy/graphene composite (EO/GR) as a route to ultrahigh thermally conductive yet mechanically robust nanocomposites. Assisted by PEG, the EO/GR composite is prepared by a simple blending method. The thermal conductivity of the prepared composite can reach to 10.17 W m(-1) K-1, and its electromagnetic interference shielding effectiveness (EMI SE) shielding efficiency is about 50 dB. The ultrahigh thermally conductive composite is mechanically robust and thermal stable. The ultrahigh thermal conductivity of the composite might be originated from the improved interfacial compatibility between EO and GR, which facilitates the successful preparation of composite at a high loading fraction of GR. Highly filled graphene in the matrix makes it possible to form massive GR-GR thermal conductive paths, which contribute to the ultrahigh thermal conductivity of the composite. This work provides an effective and simple method to prepare ultrahigh thermally conductive yet mechanically robust epoxy composites.