▎ 摘　　要

High curing temperature and large brittleness are two bottlenecks that prevent the sustainable development of thermally resistant thermosetting resins. However, simultaneously overcoming the bottlenecks without sacrificing the thermal stability is still a great challenge. Herein, a novel multifunctional hybrid (GO/MnMOF) comprised of graphene oxide (GO) and a manganese based metal-organic framework (MnMOF) was fabricated and characterized. Then, the GO/MnMOF hybrid was used to prepare a new type of toughened cyanate ester (CE) resin with significantly reduced curing temperature, low dielectric loss and high thermal resistance. In particular, the addition of only 0.5 wt% of GO/MnMOF can reduce the postcuring temperature of CE from 240 degrees C to 220 degrees C and the curing temperature continuously decreased as the content of GO/MnMOF increased. Besides, the integrated performance of the modified resin containing 0.5 wt% GO/MnMOF (0.5GO/MnMOF/CE) was much better than those of original CE resin, including its thermal, mechanical and dielectric properties; this allows progress on solving the two bottlenecks of thermally resistant thermosetting resins. It should be noted that the role of GO/MnMOF on improving the catalysis and performance of CE resin was not due to a simple combination of GO and MnMOF, but a significant synergistic effect. The attractive performance of GO/MnMOF/CE demonstrates that GO/MnMOF is an efficient multifunctional modifier, and the mechanism revealed herein provides a new strategy to develop high performance CE resins with significantly improved comprehensive properties through controlling the structure of the crosslinked network.