Liu C F, Sun R C, Zhang A P, Ren J L, Wang X A, Qin M H, Chao Z N, Luo W
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
Carbohydr Res. 2007 May 21;342(7):919-26. doi: 10.1016/j.carres.2007.02.006. Epub 2007 Feb 13.
The homogeneous chemical modification of sugarcane bagasse cellulose with succinic anhydride using 1-allyl-3-methylimidazolium chloride (AmimCl) ionic liquid as a reaction medium was studied. Parameters investigated included the molar ratio of succinic anhydride/anhydroglucose units in cellulose in a range from 2:1 to 14:1, reaction time (from 30 to 160min), and reaction temperature (between 60 and 110 degrees C). The succinylated cellulosic derivatives were prepared with a low degree of substitution (DS) ranging from 0.071 to 0.22. The results showed that the increase of reaction temperature, molar ratio of SA/AGU in cellulose, and reaction time led to an increase in DS of cellulose samples. The products were characterized by FT-IR and solid-state CP/MAS (13)C NMR spectroscopy, and thermal analysis. It was found that the crystallinity of the cellulose was completely disrupted in the ionic liquid system under the conditions given. The data also demonstrated that homogeneous modification of cellulose with succinic anhydride in AmimCl resulted in the production of cellulosic monoester. The thermal stability of the succinylated cellulose decreased upon chemical modification.
研究了以1-烯丙基-3-甲基咪唑氯盐(AmimCl)离子液体为反应介质,用琥珀酸酐对甘蔗渣纤维素进行均相化学改性。研究的参数包括纤维素中琥珀酸酐/脱水葡萄糖单元的摩尔比,范围为2:1至14:1,反应时间(30至160分钟),以及反应温度(60至110摄氏度)。制备的琥珀酰化纤维素衍生物的取代度(DS)较低,范围为0.071至0.22。结果表明,反应温度、纤维素中SA/AGU的摩尔比以及反应时间的增加导致纤维素样品的DS增加。通过傅里叶变换红外光谱(FT-IR)、固态交叉极化/魔角旋转(13)C核磁共振光谱(CP/MAS (13)C NMR)以及热分析对产物进行了表征。发现在给定条件下,纤维素的结晶度在离子液体体系中完全被破坏。数据还表明,在AmimCl中用琥珀酸酐对纤维素进行均相改性会生成纤维素单酯。化学改性后,琥珀酰化纤维素的热稳定性降低。