▎ 摘　　要

NOVELTY - Polyurethane-based wave-absorbing composite material comprises thermoplastic polyurethane substrate and a hydro-gasification semicoke graphene- graphene composite absorbent, whose content is 0.84-30 wt.% and the rest is thermoplastics polyurethane. USE - Polyurethane-based wave-absorbing composite material. ADVANTAGE - The polyurethane-based wave-absorbing composite material has excellent electromagnetic wave absorbing performance, flexibility, thermal stability, and dispersibility. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a preparation method of the polyurethane-based wave-absorbing composite material comprising (1) carrying out oxidation treatment to the hydrogasification semi-coke; (2) ultrasonically dispersing the oxidized hydrogenated gasified semicoke powder and graphene oxide in water, then mixing the two, stirring, filtering, and freeze-drying; (3) subjecting freeze-dried powder for annealing treatment to obtain composite absorbent; (4) adding composite absorption agent into the thermoplastic polyurethane solution, performing ultrasonic treatment, stirring, and drying to obtain composite material.