木质素无机杂化纳米颗粒的自组装构建及应用基础研究

Lignin is the aromatic polymer from plants having anti-UV, anti-aging and three-dimensional network structure. Enzymatic hydrolysis lignin from the biorefining industry retains the original lignin macromolecule structure and has excellent anti-UV and anti-oxidant functions, which is an ideal raw material for preparing biomass-based functional materials. However, the serious accumulation, dark color and poor mechanical properties for materials of the industrial lignin have become the bottleneck of its application in polymer materials. In this project, enzymatic hydrolysis lignin will be used as the raw material to prepare negative and positive amphoteric lignin, which will be further used to prepare light-colored lignin/inorganic hybrid nanoparticles having anti-UV, anti-aging and mechanical enhancement properties by an in-situ reaction self-assembly technology, and its application in polymer materials of the lignin/inorganic hybrid will be systematically studied. Furthermore, the influence of the molecular structure of amphoteric lignin on its microstructure and assembly characteristics with inorganic particles will be investigated. The ordered assembly of lignin and inorganic particles can be realized based on the regulation of intermolecular forces between them, and the influence mechanism of the intermolecular forces such as hydrogen bonding and static electricity on the preparation of lignin/inorganic particles will be elucidated. The key technologies and scientific problems in the preparation of lignin/inorganic hybrid particles and its application in polymer materials will be solved and clarified. The expected research results will explore a new way for the large-scale utilization of lignin, which is of great theoretical significance and practical value for promoting the sustainable development of the biological refining industry. and the green development of functional polymer materials.

木质素是植物中具有防紫外、抗老化功能及三维网络结构的芳香族酚类聚合物。生物炼制工业产生了大量酶解木质素，较好地保留了原木质素大分子结构，是制备木质素基功能材料的理想原料。由于其无规结构产生的严重聚集和较深的颜色、增强效果差，成为在高分子材料中应用的瓶颈。本项目以酶解木质素为原料，制备阴阳离子两性木质素，采用原位反应自组装技术制备颜色浅且具有防紫外抗老化、增强等功能的木质素无机杂化纳米颗粒，并探索其在高分子材料中的应用。深入研究两性木质素的结构特征对微结构及与无机颗粒自组装特性的影响机理，基于作用力的调控实现木质素与无机颗粒的有序组装，阐明分子间作用力对杂化颗粒构建的影响机制；解决与阐述木质素杂化颗粒构建及在高分子材料中应用的关键技术和科学问题。研究成果将开拓工业木质素规模化利用的新途径，对于无规天然聚合物研究、生物炼制行业及高分子材料可持续和绿色化发展具有重要科学意义和应用价值。

本项目通过化学改性和微结构调控，成功制备了系列木质素/纳米无机氧化物复合材料，并成功将其应用于极性和非极性高分子材料中。（1）成功制备了系列季铵化木质素，探究了季铵化木质素自身微结构调控规律；（2）通过沉淀法制备了表面亲水和疏水的两种木质素/SiO2纳米复合颗粒，并探究了其在高密度聚乙烯和水性聚氨酯中的应用；（3）通过水热法、溶胶凝胶法、溶剂诱导自组装法分别制备了三种木质素/TiO2纳米复合颗粒，并探究了其在水性聚氨酯抗老化领域中的应用；（4）通过沉淀法和水热法制备了三种木质素/ZnO纳米复合颗粒，并探究了其在水性聚氨酯中的应用。（5）进一步研究木质素基碳材料的构建机理及其与无机氧化物的复合机理，探索在光催化剂和储能领域的中应用。在研期间共发表SCI论文14篇,EI论文1篇；申请授权中国发明专利11件，美国专利2件；获得2020年度广东省科技进步一等奖1项，举办国内木质素专题会议2次；培养博士后2名、博士生2名、硕士生5名。本项目成功将生物质资源木质素开发成具有光学性能的纳米复合功能材料，开辟了木质素在高分子材料功能助剂领域的应用空间，有望实现木质素在高分子材料领域的规模应用。