一锅法合成氨基化纳米纤维素及其性能表征

为实现纳米纤维素衍生物的绿色高效制备,以过硫酸铵为氧化剂,基于机械力化学作用,在微波-水热条件下氧化降解竹浆粕得到羧基化纳米纤维素(CNC),然后与二乙烯三胺发生缩合反应,实现水相中氨基化纳米纤维素(ACNC)的一锅法合成,并对其性能进行研究。结果表明:ACNC呈棒状,直径为10~40 nm,长度为50~300 nm, 氨基的接枝率为6.29%;ACNC的晶型并未发生改变,仍为纤维素Ⅰ型,结晶度由竹浆粕的59%增加到79%;ACNC的热稳定性较竹浆粕并未显著下降,但较CNC显著提高,说明CNC表面接枝氨基后热稳定性能得到改善;该制备方法绿色高效,得到的纤维素衍生物有望在生物固化和物理性能增强方面发挥作用。

One-pot synthesis and characterization of aminated cellulose nanocrystals

In order to realize green preparation of nanocellulose derivatives, ammonium persulfate was used to oxidize bamboo pulp fibers to obtain carboxylated nanocellulose (CNC) under microwave-hydrothermal condition based on mechanical force chemistry. Then condensation reaction between CNC and diethylenetriamine was carried out in the aqueous phase to realize the one-pot synthesis of aminated nanocellulose (ACNC), and its properties were explored. The results show that ACNC is rod-shaped with a diameter of 10-40 nm and a length of 50-300 nm, and the grafting ratio of ACNC is 6.29%. The crystal form of ACNC is still cellulose type I, besides the crystallinity increases from 59% to 79%. The thermal stability of ACNC is not significantly lower than that of bamboo fiber, but it is significantly higher than that of CNC, indicating that the thermal stability of CNC is improved after grafting amino groups. The preparation method is green and efficient, and the obtained cellulose derivatives are expected to play a role in the field of biosolidification and physical property enhancement.