▎ 摘　　要

NOVELTY - Preparing graphene/polytetrafluoroethylene film involves melt-extruding graphene-added polytetrafluoroethylene, calendering into a film, biaxially stretching, and then using on the upper and lower surfaces. The temperature is chilled at different temperatures and then heat-set. The method involves uniformly mixing the polytetrafluoroethylene powder and graphene, silica aerogel uniformly, heating and melting in the extruder to form a melt extrusion, and calendering into a composite base film, streching the base film longitudinally, and then transversely, such that the upper and lower surfaces of the base film are chilled by liquid nitrogen, and a gradient microporous structure is formed inside the base film by using a cooling temperature difference between the upper and lower surfaces in the transverse stretching process. The upper surface chill surface temperature is 180 degrees C, and the lower surface chill surface temperature is 100 degrees C. USE - Method for preparing graphene/polytetrafluoroethylene film for sewage treatment. ADVANTAGE - The method enables to prepare graphene/polytetrafluoroethylene film, which has a wide pore size distribution, improves the filtration water flow rate and the purification effect, enhances the synergy with the graphene, enhances the adsorption effect, and improves the adsorption efficiency of the sewage. DETAILED DESCRIPTION - The chilling is completed, heat setting, cooling to room temperature, winding to obtain graphene/polytetrafluoroethylene film for sewage treatment.