▎ 摘　　要

NOVELTY - Preparing a graphene-based polymer composite nerve catheter involves slowly adding ammonium nitrate and sodium acetate to concentrated sulfuric acid while stirring, then adding flake graphite to the mixture. The molar ratio of concentrated sulfuric acid, ammonium nitrate, sodium acetate and flake graphite is 0.15-0.2:0.5-0.8:0.2-0.4:1 and stirred in a water bath at 30-50 degrees C for 30-50 minutes. The reaction solution is poured into deionized water and filter with suction to obtain a solid product. The above solid product is dried and then heated it at a high temperature at a rate of 60-120s to 900-1050 degrees C, and then cooled down naturally to obtain expanded graphite for use. The potassium permanganate and phosphorus pentoxide are slowly added to concentrated sulfuric acid, and then added the above-mentioned expanded graphite to the mixed solution. The molar ratio of concentrated sulfuric acid, potassium permanganate, phosphorus pentoxide and expanded graphite. USE - Method for preparing graphene-based polymer composite nerve catheter. DETAILED DESCRIPTION - Preparing a graphene-based polymer composite nerve catheter involves slowly adding ammonium nitrate and sodium acetate to concentrated sulfuric acid while stirring, then adding flake graphite to the mixture. The molar ratio of concentrated sulfuric acid, ammonium nitrate, sodium acetate and flake graphite is 0.15-0.2:0.5-0.8:0.2-0.4:1 and stirred in a water bath at 30-50 degrees C for 30-50 minutes. The reaction solution is poured into deionized water and filter with suction to obtain a solid product. The above solid product is dried and then heated it at a high temperature at a rate of 60-120s to 900-1050 degrees C, and then cooled down naturally to obtain expanded graphite for use. The potassium permanganate and phosphorus pentoxide are slowly added to concentrated sulfuric acid, and then added the above-mentioned expanded graphite to the mixed solution. The molar ratio of concentrated sulfuric acid, potassium permanganate, phosphorus pentoxide and expanded graphite is 8-10:0.2 0.4: 0.2 0.4: 1,40 60 degrees C in a water bath and continuous stirring for 4-6 hours, then pour the reaction solution into deionized water, added hydrogen peroxide solution, the amount of hydrogen peroxide added is the molar amount of expanded graphite dilute hydrochloric acid is added to adjust the pH value of the solution to 6.5-7.5, added deionized water to centrifuge and washed to obtain a high-concentration graphene oxide dispersion, which is ready for use. The printing ink preparation configuration is 50-80mg/mL sodium alginate solution, which is printing ink one. The graphene dispersion is adjusted to 8-20mg/mL, added 0.5-2 vol.% ethylenediamine solution, the volume ratio of graphene dispersion to ethylenediamine solution is 100:0.6-3 and stirred fully and set aside for printing ink two. The 3D printing rGO catheter adopts a coaxial bi-material 3D printing needle. The first ink passes through the main printing needle of the 3D printer to give an extrusion pressure of 0.002-0.0.2-5mL/min. The receiving box contains 1-10 vol.% ethylenediamine solution. The printed sample is put in a 40-100 degrees C water bath to heated it. At this time. The printing ink is used as a sacrificial material to dissolve in the water, and the graphene oxide is dissolved in the ethylenediamine and partially reduced and self-assembled in an amine environment to form a macroscopic three-dimensional rGO catheter, which is freeze-dried for use. An argon is used as the protective gas to burn and reduce the dried rGO tube. The burning temperature is controlled within 1000 degrees C to improve the conductivity of the rGO tube. The polymer is dissolved in dichloromethane, the polymer concentration after dissolution is 30-400mg/mL, after fully dissolved, soak the rGO catheter in the above liquid, soaked for a period of time until the liquid fills the graphene stent of the rGO catheter. The rGO catheter is taken out and dried under natural conditions, and the graphene-based polymer composite nerve catheter is prepared.