▎ 摘　　要

NOVELTY - Preparing modified graphene oxide comprises mixing graphene oxide, solvent and modifying agent, and reacting to obtain modified graphene oxide, where the modifying agent is diamine composite containing two primary amine groups. USE - The method is useful in composite pipe material (claimed) and preparing implanted medical appliances. ADVANTAGE - The modified oxidation graphene and polyimide has high compatibility, and can improve the lubricity, mechanical strength and toughness of the composite pipe. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: modified graphene oxide prepared by the preparation method; preparing composite pipe, comprising dispersing the modified graphene oxide in solvent, adding monomers for preparing polyimides, reacting, preparing precursor solution, treating core wire at least once with the precursor solution, subjecting the precursor solution loaded on the core wire to imidization treatment after each treatment, and pulling the core to obtain the composite pipe; and composite pipe material, prepared by the preparation method.