▎ 摘　　要

NOVELTY - Preparation of nano composite flame retardant containing DOPO involves dispersing graphene matrix in an organic solvent in the presence of inert gas, silane containing isocyanate and catalyst (A) at 30-100 degrees C for 24 hours to modify graphene, adding phosphorus compound, water and another catalyst(B), stirring at room temperature, carrying out sol-gel reaction, and removing solvent by distillation under reduced pressure. The catalyst (B) is chosen from ammonia, acetic acid, hydrochloric acid, sulfuric acid and hydrofluoric acid. USE - Preparation of nano composite flame retardant for polymer matrixes of epoxy resin and polycarbonate. ADVANTAGE - The nano composite flame retardant having improved dispersity of graphene and fire resistance is produced. DETAILED DESCRIPTION - Preparation of nano composite flame retardant involves dispersing graphene matrix in an organic solvent in the presence of inert gas, silane containing isocyanate and catalyst (A) at 30-100 degrees C for 24 hours to modify graphene, adding organic phosphorus compound (DOPO) water and another catalyst (B), stirring at room temperature, carrying out sol-gel reaction, and removing solvent by distillation under reduced pressure. The catalyst (A) is chosen from N,N-dimethyl cyclohexylamine , bis(2-dimethylaminoethyl)ether, N,N,N', N'-tetramethylethylenediamine alkyl diamine, triethylamine, N,N-dimethylbenzylamine, N-ethyl morpholine, N-methylmorpholine, N,N'-diethyl piperazine, triethanolamine, pyridine, N,N'-dimethyl pyridine and dibutyltin dilaurate. The catalyst (B) is chosen from ammonia, acetic acid, hydrochloric acid, sulfuric acid and hydrofluoric acid.