▎ 摘　　要

NOVELTY - Preparation of flexible graphene/permeable fiber composite microwave absorbing material includes placing permeable fiber preform in a muffle furnace, under air atmosphere, heat treating, cooling, respectively washing with acetone and deionized water and drying, coating the surface of treated permeable fiber with graphene oxide aqueous solution, drying, repeating the coating step for multiple times, placing the graphene oxide-coated permeable fiber in a muffle furnace, heat treating under the protection of argon gas or nitrogen atmosphere, and forming graphene/fiber. USE - Preparation of flexible graphene/permeable fiber composite microwave absorbing material (claimed). ADVANTAGE - The method provides flexible graphene/permeable fiber composite microwave absorbing material, which has adjustable absorption frequency, minimum reflection loss of up to - 45 dB, reflection loss frequency width of less than 10 dB at 0-4.2 GHz, and stable electromagnetic wave absorbing property after bending. DETAILED DESCRIPTION - Preparation of flexible graphene/permeable fiber composite microwave absorbing material comprises placing permeable fiber preform in a muffle furnace, under air atmosphere, heat treating at 400-600 degrees C, keeping the temperature for 1-3 hours, cooling, respectively washing with acetone and deionized water and drying, coating the surface of treated permeable fiber with graphene oxide aqueous solution, drying at 40-80 degrees C, repeating the coating step for multiple times, placing the graphene oxide-coated permeable fiber in a muffle furnace, heat treating under the protection of argon gas or nitrogen atmosphere at 400-700 degrees C for 0.5-3 hours, forming graphene/fiber, vacuum impregnating with polydimethylsiloxane (PDMS) for 5-30 minutes, curing in drying box for 1-10 hours at 60-100 degrees C, and obtaining flexible reduction graphene/fiber composite material.