以对甲苯磺酸为催化剂,滤纸和乙酸为原料,采用一锅法制备了乙酰化纤维素纳米晶(CNC-Ac),并优化了反应条件。结果表明,当对甲基苯磺酸和滤纸的质量比为1∶1时,较佳反应条件为:90%(wt,质量分数)乙酸水溶液和对甲苯磺酸质量比为10∶1,反应温度为90℃,反应时间为90min,该条件下得到的CNC-Ac的产率为79%,分子取代度为0.8。采用SEM、FT-IR、XRD等对CNC-Ac的结构形态进行了表征。研究了CNC-Ac对醋酸纤维素膜的增强性能,结果表明,当CNC-Ac的质量分数为2%时,得到的醋酸纤维素-CNC-Ac纳米复合膜的拉伸强度和断裂伸长率分别为纯醋酸纤维素膜的6.6倍和1.3倍。
The acetylated cellulose nanocrystals (CNC-Ac) were prepared by a one-pot method using p-toluenesulfonic acid as a catalyst,filter paper and acetic acid as raw materials,and the reaction conditions were optimized.The results shown that when the mass ratio of p-toluenesulfonic acid to filter paper was 1∶1,the optimum conditions were as follows: the mass ratio of 90wt% acetic acid aqueous solution to p-toluenesulfonic acid was 10∶1,and the reaction temperature was 90℃.The reaction time was 90 min.The yield of obtained CNC-Ac was 79%,and the degree of molecular substitution was 0.8.The structure and morphology of CNC-Ac were characterized by SEM,FT-IR and XRD.The enhancement performance of CNC-Ac on cellulose acetate membrane was studied.The results showed that when the mass percentage of CNC-Ac was 2%,the obtained cellulose acetate-CNC-Ac nanocomposite membrane was better than pure cellulose acetate membrane.The tensile strength and the elongation at break were increased by 6.6 times and 1.3 times,respectively.
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基金资助
国家自然科学基金(21376041,21878036)
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