▎ 摘　　要

NOVELTY - Cyclotriphosphazene derivative (I) is new. USE - Cyclotriphosphazene derivative used in the preparation of flame-retardant polymers (claimed). ADVANTAGE - The cyclotriphosphazene derivative is prepared in simple and cost-effective manner under mild reaction condition. DETAILED DESCRIPTION - Cyclotriphosphazene derivative of formula (I) is new.. n=natural number from 2-6. An INDEPENDENT CLAIM is included for a methods for preparing a cyclotriphosphazene-modified graphene, which involves: (A) adding hexachlorocyclotriphosphazene, sodium 2-naphtholate, and acid binding agent to dichloromethane, mixing and dissolving under the protection of nitrogen, heating to 60-80 degrees C, stirring and refluxing for 3-6 hours; (B) filterting reaction solution, washing, filtering with suction, drying, and separating and purifying by column chromatography to obtain trinaphthyloxytrichlorocyclotriphosphazene; (C) adding the trinaphthyloxytrichlorocyclotriphosphazene and bridging agent obtained to dichloromethane, mixing and dissolving, stirring and reacting for 1-3 hours under nitrogen protection and ice bath, heating to 60-80 degrees C, stirring and refluxing for 3-6 hours to obtain fully substituted cyclotriphosphazene solution; and (D) adding graphite oxide to the fully substituted cyclotriphosphazene solution, mixing ultrasonically, then adding cyclohexylcarbodiimide and 4-dimethylaminopyridine, then heating to 60-80 degrees C, stirring and refluxing for 3-6 hours, filtering, washing, suction filtering and freeze-drying the reaction solution to obtain product.