▎ 摘　　要

NOVELTY - N-methyl pyrrolidone and oxidized graphene are weighed and added to three-necked bottle. Then, graphene oxide, polyvinylpyrrolidone and polyvinylidene fluoride are added to bottle. The bottle is placed in water bath and stirred, to obtain casting film liquid. The casting film liquid is placed on clean glass plate, film is coated, dipped in distilled water, to obtain the composite ultrafiltration membrane. The obtained composite ultra-filtration membrane is immersed in distilled water and dried, to obtain oxidized graphene/polyvinylidene fluoride composite ultrafiltration membrane. USE - Preparation of graphene oxide/polyvinylidene fluoride composite ultrafiltration membrane. Uses include but are not limited to food industry, drinking water preparation, pharmaceutical industry, biotechnology, chemical field and environmental engineering field. ADVANTAGE - The method enables preparation of graphene oxide/polyvinylidene fluoride composite ultrafiltration membrane having excellent hydrophobicity and anti-pollution performance. DETAILED DESCRIPTION - N-methyl pyrrolidone and oxidized graphene are weighed at 2-24 degrees C in mass ratio of 8-85:1, respectively and added into three-necked bottle under the ultrasonic condition of 240-260 W for 1.8-2 hours. Then, graphene oxide, polyvinylpyrrolidone and polyvinylidene fluoride are weighed in a mass ratio of 1:1:1-18, respectively and added to the three-necked bottle. The bottle is placed in water bath at 42-48 degrees C and continuously stirred at speed of 40-600 rpm for 11-13 hours, to obtain the casting film liquid. The casting film liquid is placed on clean glass plate, coating film thickness is set to 140-160 mu m with coating device, film is coated for 5-10 minutes, dipped in distilled water for 35-45 seconds and dropped, to obtain the composite ultrafiltration membrane. Then, the obtained composite ultra-filtration membrane is immersed in distilled water for 12 hours, distilled water is changed for every 4 hours and dried, to obtain oxidized graphene/polyvinylidene fluoride composite ultrafiltration membrane.