Aramid fiber/polyimide composite material and preparation method thereof

The invention discloses an aramid fiber/polyimide composite material and a preparation method thereof. The method comprises the following steps: uniformly mixing aramid fiber with pyromellitic dianhydride, placing the obtained mixture in a self-made microwave device, carrying out a grafting reaction, and radiating under a microwave radiation frequency of 0.5-5GHz and a radiation dose of 0.1-2mW/cm for 1-240s; carrying out a pre-polycondensation reaction on aramid fiber grafted pyromellitic dianhydride and ethene diamine at 50-70DEG C to generate a aramid fiber/polyimide prepolymer; and carrying out melt blending on the prepolymer and polyimide through a double screw extruder to prepare the aramid fiber/polyimide composite material. The composite material has excellent transverse tensile strength, and can be used in the aviation and aerospace field.