Laboratory of Papermaking, School of Textiles & Clothing, Jiangnan University, Wuxi 214122, China; Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China; Department of Chemical Engineering, University of New Brunswick, Fredericton E3B5A3, Canada.
Laboratory of Papermaking, School of Textiles & Clothing, Jiangnan University, Wuxi 214122, China; Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University, Wuxi 214122, China; Key Laboratory of Pulp and Paper Science & Technology of Ministry of Education of China, Qilu University of Technology, Jinan 250353, China.
Carbohydr Polym. 2017 Aug 1;169:83-91. doi: 10.1016/j.carbpol.2017.03.043. Epub 2017 Mar 15.
N,N,N-trimehtyl chitosan (TMC) is a water-soluble derivate of chitosan, which has been widely used as a biomedical material due to its excellent biocompatibility, biodegradability and bacterial properties. To date, TMC can only be prepared by the quaternization of chitosan using alkyl halide or dimethyl sulfate. However, alkyl halide and dimethyl sulfate are highly toxic, cancerigenic for humans, and harmful to the environment. This paper puts forward a novel approach to preparing TMC using dimethyl carbonate as a methylation reagent in an ionic liquid. The as-synthesized O-methyl-free TMC was characterized using NMR, FTIR, XRD and TG analyses. The results showed that TMC with a degree of quaternization of 9.11% was successfully obtained and the crystallinity of chitosan decreased with the increasing degree of N-methylation, the thermal stability of TMC was lower than that of chitosan. Furthermore, the effects of the dose of ionic liquid and dimethyl carbonate were disscussed.
N,N,N-三甲基壳聚糖（TMC）是壳聚糖的水溶性衍生物，由于其良好的生物相容性、生物降解性和抗菌性能，已被广泛用作生物医学材料。迄今为止，TMC 只能通过壳聚糖与卤代烷或硫酸二甲酯的季铵化反应来制备。然而，卤代烷和硫酸二甲酯毒性很高，对人类具有致癌性，对环境也有害。本文提出了一种在离子液体中使用碳酸二甲酯作为甲基化试剂来制备 TMC 的新方法。采用 NMR、FTIR、XRD 和 TG 分析对合成的 O-甲基化 TMC 进行了表征。结果表明，成功地获得了季铵化度为 9.11%的 TMC，壳聚糖的结晶度随 N-甲基化程度的增加而降低，TMC 的热稳定性低于壳聚糖。此外，还讨论了离子液体和碳酸二甲酯用量的影响。
