不同晶型纤维素纳米晶体的制备与表征的比较研究。
A comparative study on the preparation and characterization of cellulose nanocrystals with various polymorphs.
机构信息
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China; United Lab of Plant Resources Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China; United Lab of Plant Resources Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
出版信息
Carbohydr Polym. 2018 Sep 1;195:18-28. doi: 10.1016/j.carbpol.2018.04.039. Epub 2018 Apr 12.
Polymorphic changes of cellulose nanocrystals (CNCs) are strongly associated with its properties and applications. In this study, CNCs with different polymorphs were produced by a simple polymorphic transformation treatment. Cellulose I nanocrystals were produced by typical sulfuric acid hydrolysis (CNC-I). Cellulose II nanocrystals were prepared by two different methods: (1) sulfuric acid hydrolysis of cellulose previously mercerized with 18.5 wt% NaOH (CNC-II), (2) mercerization of CNC-I with 18.5 wt% NaOH (MCNC-II). Cellulose III nanocrystals were prepared by ethylenediamine treatment of CNC-I (ECNC-III). The polymorphic changes of CNCs, and their properties including morphology, crystallinity, thermal stability, and re-dispersion ability were systematically investigated. The results showed that the other properties of CNC-II and MCNC-II were quite different from each other except for the morphology. The morphology of polymorphic transformed CNCs were strongly relate to the fashion of cellulose chains arrangement. Both CNC-II and MCNC-II exhibited a rod-like shape with short lengths, whereas the ECNC-III showed relatively long length, like CNC-I.
纤维素纳米晶（CNC）的多晶型变化与其性能和应用密切相关。在本研究中，通过简单的多晶型转变处理制备了具有不同多晶型的 CNC。通过典型的硫酸水解制备纤维素 I 纳米晶（CNC-I）。通过两种不同的方法制备纤维素 II 纳米晶：（1）用 18.5wt%NaOH 对纤维素进行丝光化后再进行硫酸水解（CNC-II），（2）用 18.5wt%NaOH 对 CNC-I 进行丝光化（MCNC-II）。通过乙二胺处理 CNC-I 制备纤维素 III 纳米晶（ECNC-III）。系统研究了 CNC 多晶型变化及其性能，包括形态、结晶度、热稳定性和再分散能力。结果表明，除形态外，CNC-II 和 MCNC-II 的其他性能差异很大。多晶型转化 CNC 的形态与纤维素链排列方式密切相关。CNC-II 和 MCNC-II 均呈现出短而直的棒状形态，而 ECNC-III 则呈现出与 CNC-I 相似的相对较长的形态。
Zotero 插件