▎ 摘　　要

NOVELTY - Polytetrafluoroethylene modified filler comprises polydopamine, reducing graphene sheet and organic fiber. The filler has a three-dimensional network framework structure. The reduction graphene sheet is attached to the surface of the organic fiber by physical adsorption. A portion of the poly dopamine is combined with the reduced graphene sheet to form a nano sheet. The other portion is connected with an organic fiber surface. The organic fiber is a polyimide or polyether ether ketone, and is chopped fiber. USE - The polytetrafluoroethylene modified filler is useful in a modified polytometrafluoethylene composite material, which is useful as a sealing material (claimed). ADVANTAGE - The polytetrafluoroethylene modified filler is capable of greatly reducing material friction coefficient and reducing wear rate, and keeping excellent mechanical property of the material. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: (1) preparation method of the polytetrafluoroethylene modified filler comprising providing a solution of organic fiber and oxidized graphene sheet; dipping the organic fiber in the oxidized and graphene nano-sheet solution to obtain mixed dipping liquid; adding dopamine hydrochloride and Tris-HCl buffer solution into the mixed dipping solution, heating and reacting; and (2) modified polytetrafluoroethylene composite material, prepared by pressing and sintering the mixed powder, where the mixed powder comprises polytetrafluoroethylene and modified filler, and the modified filler is the polytetrafluoroethylene modified filler; and (3) preparation method of modified polytetrafluoroethylene composite material, comprising: preparing polytetrafluoroethylene modified filler; mixing the polytetrafluoroethylene and the polytetrafluoroethylene modified filler to obtain mixed powder; and pressing and sintering the mixed powder. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of polytetrafluoroethylene modified filler structure.