▎ 摘　　要

As the primary matrix resin for advanced composites, bismaleimide (BMI) is highly demand in the aerospace field, but its development is limited due to the brittleness of the cured resin. Graphene oxide (GO) is often used as a toughening filler for thermosetting resins due to the special structure, but the dispersion and interface interaction with the matrix have been puzzling. To improve toughening effect of GO in BMI, we proposed a strategy to selectively functionalize the surface of GO. In our work, GO was functionalized by maleic anhydride (MAH) and BMI resin (QY8911-IV) was selected as the matrix of the nanocomposite. A series of characterizations demonstrated that MAH has been bonded to the surface of GO and modified GO still maintained a nanoscale dimension. Moreover, the short-chain of MAH can provide a bridging effect. The impact strength of MAH-GO/QY8911-IV nanocomposite was 29.06 kJ/m(2) at 0.05 wt% loading of MAH-GO, which was 93.2% higher than that of neat QY8911-IV. Morphology analysis revealed that the fracture behavior of MAH-GO modified nanocomposites changed from brittle to ductile. Meanwhile, the nanocomposite showed great heat resistance and thermal stability, so it could be expected to be popularized in high-load and high-temperature working environments.