杨絮纤维细胞壁超微结构及化学组成对其微纤化性能的影响

Poplar seeds appendage hairs well known as Poplar blowballs, are harmful to the environment as it is very difficult to be collect them effectively due to their low density and flying characters. Previous studies have shown that Poplar blowball fibers own great potential to be used as a raw material for the production of nanocellulosic fibrils (NCF) as the energy consumed during the separation was very low. In order to explain why NCF is so easy to be isolated from Poplar blowball fibers, the ultrastructure and chemical compositions of the fiber cell walls will be systematically studied with various advanced techniques for structural and chemical characterization. The fine physical structure model of the cell walls will be established. Meanwhile, NCF will be isolated from the Poplar blowball fibers with optimal processes of high-pressure homogenization and high intensity ultrasonication. The energy consumption and the quality of the NCF will be quantitatively evaluated, which will be explained from the aspect of ultrastructure and chemical compositions of cell walls.These studies will not only contribute to the comprehensive understanding of cell wall structures and chemical compositions of poplar blowball fibers, but also provide meaningful inspiration for the efficient isolation of NCF from other plant fibers.

杨树种缨纤维俗称杨絮，质轻易漂浮，收集麻烦，对环境有一定危害。前期研究显示，杨絮纤维制备纤维素纳米纤丝（NCF）的能耗很低，因此具有很好的开发利用价值。为了阐明杨絮纤维易于微纤化的根本原因，本项目拟集成应用多种成像、结构和力学表征手段，系统研究杨絮纤维细胞壁超微构造和化学组成，比较分析其与木材细胞壁之间的差异，从而提出杨絮纤维细胞壁物理结构模型。在此基础上，采用高压均质化法与高频超声波破碎法制备纳米纤维素（NCF）溶胶，优化工艺，并对其微纤化解离难易程度和溶胶质量进行定量评价；从细胞壁结构和化学组成角度对其独特的微纤化特性进行解释。通过上述研究，不仅可以获得杨絮纤维细胞壁结构及化学组分的系统知识，还可能为从其它植物纤维高效提取NCF提供有意义的借鉴。

杨树种缨纤维俗称杨絮，质轻易漂浮，收集麻烦，对环境有一定危害。本项目以杨絮纤维为研究对象，从纤维细胞壁的壁层构造、化学组分分布等入手，利用现代研究手段和先进方法，深入研究了纤维细胞壁超微构造和物质组成。采用高分辨率原子力显微镜等手段揭示了纤维细胞壁的壁层构造，并解析了细胞壁超微结构；基于纤维细胞壁精细构造的研究结果，并结合前人的研究成果，提出了杨絮纤维细胞结构模型。对杨絮纤维的酶解性能进行了分析，讨论了各化学成分在其降解过程中的作用，采用高频超声波破碎法制备纳米纤维素（NCF）溶胶，优化工艺，并对其微纤化解离难易程度和溶胶质量进行定量评价；从细胞壁结构和化学组成角度对其独特的微纤化特性进行了解释。该研究促进了对杨絮纤维细胞壁精细结构的认识，研究成果将为杨絮纤维的高值利用、材料设计、生物仿生、生物能源转化及纳米纤维素制备等提供科学依据。相关研究结果发表于《Journal of Materials Science》、《Journal of wood science》、《Industrial Crops and Products》、《Holzforschung》等重要学术刊物。项目目前共计发表SCI收录学术论文12篇，培养研究生1名。