▎ 摘　　要

NOVELTY - A magnetic carbon fiber-steel fiber modified PTFE material comprises 15-20 pts. wt. magnetite, 80-90 pts. wt. PTFE, 10-15 pts. wt. carbon fiber, 5-10 pts. wt. steel fiber, 5-10 pts. wt. fluororubber powder, 5-10 pts. wt. ferric oxide, 1-3 pts. wt. graphene oxide, 5-10 pts. wt. silicon dioxide, silane coupling agent KH550 (RTM: ( gamma )-aminopropyltriethoxysilane), citric acid, acetone, ethanol, acetic acid, polyisocyanate JQ-1, dimethylformamide, 4-dimethylaminopyridine, dicyclohexylcarbodiimide and water. The fluororubber powder has a particle size of 80-200 mesh. USE - Magnetic carbon fiber-steel fiber modified PTFE material used in sealant, sensor and biomedical applications. ADVANTAGE - The PTFE material has improved tensile strength and excellent friction properties. The surface sintering state of the polytetrafluoroethylene is improved at high temperature sintering condition, so that bonding strength is significantly improved. The magnetic properties of PTFE material are increased. DETAILED DESCRIPTION - A magnetic carbon fiber-steel fiber modified PTFE material comprises 15-20 pts. wt. magnetite, 80-90 pts. wt. PTFE, 10-15 pts. wt. carbon fiber, 5-10 pts. wt. steel fiber, 5-10 pts. wt. fluororubber powder, 5-10 pts. wt. ferric oxide, 1-3 pts. wt. graphene oxide, 5-10 pts. wt. silicon dioxide, 15-20 pts. wt. silane coupling agent KH550 (RTM: ( gamma )-aminopropyltriethoxysilane), 20-30 pts. wt. citric acid having concentration of 0.1 mol/L, 20-25 pts. wt. acetone, 95% of 30-40 pts. wt. ethanol, acetic acid, 5-10 pts. wt. polyisocyanate JQ-1, 15-20 pts. wt. dimethylformamide, 10-15 pts. wt. 4-dimethylaminopyridine, 15-20 pts. wt. dicyclohexylcarbodiimide and 90-100 pts. wt. water. The carbon fiber has a median length of 75-150 mu m. The median length of the steel fiber is 50-150 mu m. The fluororubber powder has a particle size of 80-200 mesh. An INDEPENDENT CLAIM is included for preparation of magnetic carbon fiber-steel fiber modified PTFE material, which involves (i) adding carbon fiber to 95% of 20-25 pts. wt. ethanol solvent, ultrasonically dispersing uniformly, adding acetic acid to adjust the pH to 4-5, adding 8-12 pts. wt. silane coupling agent KH550, stirring for 8-15 hours, then washing with deionized water, and vacuum drying, (ii) oxidizing the graphene oxide in the remaining 95% of ethanol solvent by glow discharge plasma technology to obtain graphene peroxide, (iii) adding the obtained graphene peroxide to dimethylformamide, ultrasonically processing for 2-3 hours, stirring, then sequentially adding 4-dimethylaminopyridine, dicyclohexylcarbodiimide and the treated carbon fiber, reacting at room temperature for 18-36 hours, then washing with deionized water, and vacuum drying to obtain graphene peroxide-grafted carbon fiber, (iv) adding the fluororubber powder to the polyisocyanate JQ-1, mechanically stirring evenly, adding the dried steel fiber, stirring for 1-3 hours, washing and drying to obtain mixture, (v) adding magnetite and ferric oxide to the citric acid solution, stirring for 1-3 minutes, washing magnetite and ferric oxide were with acetone and vacuum drying, (vi) adding graphene peroxide-grafted carbon fiber, and obtained mixture and magnetite and ferric oxide, homogeneously mixing with 70-75 pts. wt. PTFE in a high-speed mixer, cold forming, sintering in air atmosphere at 360-390 degrees C to plate-like sample having diameter of 150-250 mm and thickness of 3-4 mm, (vii) immersing the plate-like sample in a dipping coating solution for 4-8 minutes, drying in an oven at 80-100 degrees C, sintering in a muffle furnace at 120-200 degrees C for 10-30 minutes and taking out. The dipping coating solution is prepared by grinding silicon dioxide with remaining PTFE and silane coupling agent KH550, dispersing in water, and evenly and ultrasonically dispersing.