【摘要】 以TEMPO氧化纤维素纳米纤丝为原料,甲基三甲氧基硅烷为改性剂,N,N-亚甲基双丙烯酰胺(MBA)为交联剂,采用溶胶凝胶法与冷冻干燥法制备出疏水纤维素纳米纤丝气凝胶。在通过对反应条件的探讨后发现,当温度为55℃,pH值=8,改性剂添加量为3 mL,反应时间在5 h以上时可以得到低密度(<0.03 g/cm~3)、高孔隙率(>98%)的气凝胶,其接触角可达130°,吸油量达到气凝胶本身质量的18倍。更多还原

【Abstract】 In this study, hydrophobic cellulose nanofibril aerogel was prepared by sol-gel method and freeze drying method with TEMPO oxidized nanocellulose(CNF) as raw material, ammonium persulfate and anhydrous sodium sulfite as initiator, methyl trimethoxy silane(MTMS) as modifier and N,N′-methylene bis-acrylamide(MBA) as crosslinking agent. Silanol was generated by hydrolysis of methyl trimethoxy silane and hydrophobic modification was carried out through self-polymerization and hydroxy reaction on the surface of CNF to generate poly-siloxane bonds. MBA was cross-linked with hydroxyl, which increased the bonding strength between fibers. After discussion of the reaction conditions, it was found that when CNF was 10 g, the temperature was 55 ℃, pH was 8, the amount of MTMS was 3 mL, and the reaction time was more than 5 h, the aerogel with excellent performance, density less than 0.03 g/cm~3, and porosity more than 98% could be obtained. FTIR and scanning electron microscope analysis confirmed the successful reaction between MTMS, MBA and CNF. The adsorption capacity of aerogel to waste oil could reach 18 times of its own mass, and the contact angle to water could reach more than 130°, showing a good hydrophobic and oil absorption performance.更多还原