▎ 摘　　要

NOVELTY - 0.5-6 Parts mass graphite oxide is mixed with 202 parts mass 85% concentration phosphoric acid, 253 parts mass phosphorus pentoxide, 100 parts mass 4,6-diamino resorcinol dihydrochloride, 1-10 parts mass tin chloride, 78 parts mass terephthalic acid and 183 parts mass phosphorus pentoxide and ultrasonically-dispersed. Then, 253 parts mass phosphorus pentoxide is added to obtained product and reacted. 4,6-Diamino resorcinol dihydrochloride and tin (II) chloride are further added to resultant mixture, and further processed, to obtain graphene/polybenzoxazole composite film. USE - Preparation of graphene/polybenzoxazole composite film (claimed). ADVANTAGE - The method efficiently and economically provides graphene/polybenzoxazole composite film having high heat resistance and mechanical property. DETAILED DESCRIPTION - 200-1500 mL Concentrated sulfuric acid is mixed with 20-100 mL concentrated hydrogen phosphate. Then, 1-10 g nano-graphite and 6-50 g potassium permanganate are added, mixed at 0-50 degrees C, stirred for 12-48 hours, cooled using 0.5-5 L distilled water. The mixture is stirred for 0.5-2 hours, filtered using 0.22 mu m microporous filtration membrane, filter cake is washed with distilled water until neutral, and filter cake is freeze-dried, to obtain graphite oxide. 0.5-6 Parts mass graphite oxide is mixed with 202 parts mass 85% phosphoric acid, 253 parts mass phosphorus pentoxide, 100 parts mass 4,6-diamino resorcinol dihydrochloride, 1-10 parts mass tin chloride, 78 parts mass terephthalic acid and 183 parts mass phosphorus pentoxide, ultrasonically-dispersed for 5-10 hours, and stirred. Then, 253 parts mass phosphorus pentoxide is added to obtained product and reacted at 60-100 degrees C for 1-5 hours under nitrogen atmosphere. 4,6-Diamino resorcinol dihydrochloride and tin (II) chloride are added to resultant mixture, reacted at 60-100 degrees C for 12-36 hours and heated to 120 degrees C for 8-24 hours. Then, terephthalic acid is added, stirred at 140-160 degrees C for 4-8 hours, and further heated to 180-200 degrees C for 3-5 hours. 183 Parts phosphorus pentoxide is added to product and reacted for 3-5 hours. The obtained film is hot-pressed using stainless steel plate at 120-240 degrees C for 0.2-2 hours under pressure of 5-300 MPa. The film is immersed in 0-30% phosphoric acid solution for 8-48 hours, and then dried at room temperature, to obtain graphene/polybenzoxazole composite film.