▎ 摘 要
NOVELTY - Preparing konjac fiber/graphene airgel involves taking 2-3 g graphite powder into a three-opening bottle, placing in ice water bath at 0-5 degrees C, stirring, slowly dropping 98% concentrated 80-100 mL sulfuric acid and 85 % concentrated 10-15 mL phosphoric acid solution at a dropping speed of 4-6 mL/min, then adding 12-15 g potassium permanganate, stirring for 20-30 min, placing in water bath, stirring and reacting for 10-12 hours at a temperature of 50-60 degrees C. USE - Method for preparing konjac fiber/graphene airgel (claimed). ADVANTAGE - The method enables to prepare konjac fiber/graphene airgel in simple, cost-effective manner, that has good hydroscopic property, excellent electrical conductivity, thermal and mechanical performance and wide market prospect. DETAILED DESCRIPTION - Preparing konjac fiber/graphene airgel involves taking 2-3 g graphite powder into a three-opening bottle, placing in ice water bath at 0-5 degrees C, stirring, slowly dropping 98% concentrated 80-100 mL sulfuric acid and 85 % concentrated 10-15 mL phosphoric acid solution at a dropping speed of 4-6 mL/min, then adding 12-15 g potassium permanganate, stirring for 20-30 min, placing in water bath, stirring and reacting for 10-12 hours at a temperature of 50-60 degrees C. The temperature of the water bath, after finishing reaction, is raised to 90-95 degrees C, continuously stirred and reacted for 25-30 min and placed in ice bath after finishing the reaction, added with 30% concentrated 4-6 mL hydrogen peroxide into the flask, stirred and mixed for 40-50 mins at -5 degrees C to 0 degrees C and filtered to obtain the filtered residue, which is centrifuged to obtain precipitate. The precipitate is subjected to ultrasonic cleaning with 5% hydrochloric acid and de-ionized water for 5-10 min, 3-5 times washed with 90% ethanol, freeze-dried, ground and sieved to obtain graphene oxide powder of 120-150 meshes. The graphene oxide powder is heated at 400-500 degrees C, reduced under the protection of argon for 1-2 hours to obtain graphene, which is added with N,N-dimethylformamide solvent, according to the solid-liquid ratio of 1:5-10 and subjected to ultrasonic treatment for 1-2 hours at 80-120 kilohertz. The lower precipitate after processing is removed to obtain an upper layer of graphene dispersion liquid. The 10-20 g konjac powder is mixed with distilled water according to the solid-liquid ratio of 1:5, mechanically stirred for 5-10 min, then added with graphene dispersion liquid according to the volume ratio of 1:1. The ultrasonic dispersion is carried out for 5-10 min, added with 2-3 wt.% sodium carbonate, 3-5 wt.% dioctylphthalate, placed in water bath, stirred and reacted for 3-5 hours at 60-70 degrees C, cooled to room temperature and reserved for 20-30 hours to form a gel state to obtain the konjak fiber/graphene aerogel. The konjak fiber/graphene aerogel is filtered, 3-5 times washed with de-ionized water, cleaned and freeze-dried to obtain konjak fiber/graphene aerogel.