Qi Yungeng, Wang Shihao, Liza Afroza Akter, Li Jimin, Yang Guihua, Zhu Wenyuan, Song Junlong, Xiao Huining, Li Haiming, Guo Jiaqi
Liaoning Key Laboratory of Lignocellulose Chemistry and BioMaterials, Liaoning Collaborative Innovation Center for Lignocellulosic Biorefinery, School of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China; Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China.
Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China.
Carbohydr Polym. 2023 Nov 1;319:121146. doi: 10.1016/j.carbpol.2023.121146. Epub 2023 Jun 24.
Nanocellulose (NC) is the desired building block for novel biomaterials. The morphology of NC is one of the core parameters impacting the functionality and property of engineered functional materials. This work aims to reveal the relationship between the product morphology and sulfuric acid hydrolysis conditions (including acid concentration, temperature and time), and to realize morphological regulation of obtained NC. Three representative products were obtained from microcrystalline cellulose via sulfuric acid hydrolysis, which are cellulose nanocrystals with broad size distribution (W-CNC, 383.9 ± 131.7 nm in length, 6 ± 2.1 nm in height) obtained by 61 % HSO, 55 °C and 90 min, cellulose nanospheres (CNS, 61.3 ± 15.9 nm in diameter) obtained by 64 % HSO, 35 °C and 75 min, and CNC with narrow size distribution (N-CNC, 276.1 ± 28.7 nm in length, 4.1 ± 0.6 nm in height), obtained by 64 % HSO, 45 °C and 45 min. The results showed that the crystallographic form of W-CNC and N-CNC are cellulose I, while cellulose I and II coexist in CNS. Only W-CNC and N-CNC can form chiral nematic structures through evaporation-induced self-assembly strategy and reflected light with specific wavelengths. In addition, the formation mechanism of CNS with cellulose I/II was proposed, which provided a better understanding of NC morphology regulation.
纳米纤维素（NC）是新型生物材料理想的构建单元。NC的形态是影响工程功能材料功能和性能的核心参数之一。本工作旨在揭示产物形态与硫酸水解条件（包括酸浓度、温度和时间）之间的关系，并实现所得NC的形态调控。通过硫酸水解从微晶纤维素中获得了三种代表性产物，分别是通过61%的硫酸、55℃和90分钟获得的长度为383.9±131.7纳米、高度为6±2.1纳米且尺寸分布较宽的纤维素纳米晶体（W-CNC），通过64%的硫酸、35℃和75分钟获得的直径为61.3±15.9纳米的纤维素纳米球（CNS），以及通过64%的硫酸、45℃和45分钟获得的长度为276.1±28.7纳米、高度为4.1±0.6纳米且尺寸分布较窄的CNC（N-CNC）。结果表明，W-CNC和N-CNC的晶体形式为纤维素I，而CNS中纤维素I和II共存。只有W-CNC和N-CNC能够通过蒸发诱导自组装策略形成手性向列相结构并反射特定波长的光。此外，还提出了纤维素I/II共存的CNS的形成机制，这有助于更好地理解NC的形态调控。
