纤维素纳米晶杂化过渡金属二硫化物纳米片的制备及其轻质高强功能材料构筑研究

Cellulose-based lightweight and high-strength composites have attracted extensive attention due to their environment-friendly and high performance. Transition metal dichalcogenides nanosheets (TMDNs) have the advantages of high modulus and versatility, making them as ideal fillers for building lightweight, high-strength and functional cellulose-based composites. However, problems such as the difficulty of preparing in large-scale and keeping high concentration dispersion in polymer matrix have hampered its development. An effective strategy for solving this bottleneck is to prepare hybrid TMDNs by liquid phase exfoliation. And the challenges are the high cost，high pollution of exfoliation reagent and difficulty in regulating size and thickness of TMDNs. The present proposal plans to prepare CNC hybrid TMDNs using cellulose nanocrystals (CNC) as liquid phase exfoliation reagent, and study the structure-activity relationship between the physicochemical structure of CNC, properties of dispersion system and the physical characteristics of TMDNs. We will establish a preparation method of TMDNs with low-cost, high-efficiency, environmentally friendly and water-dispersed. Furthermore, the CNC/TMDNs nanocomposites were fabricated by in-situ self-assembly. We aim to reveal the mechanism of non-covalent bond strengthening and functional intensification of TMDNs, and realize the construction of CNC-based lightweight, high-strength and functional materials on demand. It is expected that this planned research will not only promote the development of two-dimensional nanomaterials, but also expand the application of cellulose-based materials in high-tech fields, such as biomedicine, sensing and engineering materials.

纤维素基轻质高强复合材料因其环保、高性能得到了广泛关注，而过渡金属二硫化物纳米片（TMDNs）具有高模量、多功能特性等优点，是构建纤维素基复合材料的理想填料。然而TMDNs缺乏可大规模制备的方法及难以在基体内高浓度分散等问题一直阻碍着其发展。解决该瓶颈的有效策略是通过液相剥离制备杂化TMDNs，面临的难题是剥离分散剂的高成本、高污染和难以调控制备TMDNs。本项目拟以纤维素纳米晶（CNC）为辅助剥离剂，通过液相超声剥离制备CNC杂化TMDNs，研究CNC的物化结构、分散体系性质与TMDNs各项物性间的构效关系，建立绿色高效、水相分散的TMDNs可控制备方法。并原位自组装构筑CNC/TMDNs复合材料，探究TMDNs对材料的非共价键增强及功能强化机制，实现CNC基轻质高强功能材料的按需构筑。该项目的成功实施，不仅推动了二维纳米材料的发展，也将拓展纤维素在生物医学、传感、工程材料等领域的应用。

纤维素基轻质高强复合材料因其环保、高性能得到了广泛关注，而过渡金属二硫化物纳米.片（TMDNs）具有高模量、多功能特性等优点，是构建纤维素基复合材料的理想填料。然而TMDNs缺乏可大规模制备的方法及难以在基体内高浓度分散等问题一直阻碍着其发展。解决该瓶颈的有效策略是通过液相剥离制备杂化TMDNs，面临的难题是剥离分散剂的高成本、高污染和难以调控制备TMDNs。本项目以纤维素纳米晶（CNC）为辅助剥离剂，通过液相超声剥离制备CNC杂化TMDNs，研究了CNC的物化结构、分散体系性质与TMDNs各项物性间的构效关系，建立了绿色高效、水相分散的TMDNs可控制备方法。申请人利用纤维素纳米晶可调控的尺寸和表面化学，实现了纤维素纳米晶杂化过渡金属二硫化物的高效可调控制备（层数1-5层，尺寸50-200 nm）（Chem. Eng. J. 2022, 428, 132594.），并且实现了宽温度（0-95℃）和酸碱（1-13）的稳定水相分散，远超过了本领域文献报道。并原位自组装构筑CNC/TMDNs复合材料，可拉伸200%的纤维素纳米晶/WS2/聚氨酯柔性彩色薄膜可实现力、光、热、湿度多刺激响应柔性变色皮肤，探究了TMDNs对材料的非共价键增强及功能强化机制，实现了CNC基轻质高强功能材料的按需构筑。该项目不仅推动了二维纳米材料的发展，也拓展了纤维素在生物医学、传感、工程材料等领域的应用。.在本基金支持下，负责人已发表中科院1区SCI文章6篇（ACS Nano, 2021, 15, 19877； Chem. Eng. J. 2022, 428, 132594.； Carbohyd. Polym., 2022, 297, 119990； Compos. Sci. Technol., 2023, 231, 109801.; Chem. Commun., 2022, 58, 13349.; J. Colloid Interf. Sc., 2022, 628, 566.;），其中以唯一通讯作者发表中科院1区SCI论文3篇（ACS Nano, 2021, 15, 19877； Chem. Eng. J. 2022, 428, 132594.； Carbohyd. Polym., 2022, 297, 119990），申请并公开专利2项（CN112939082A； CN112851205B