木质基仿生智能复合材料可控构筑与变色发光机制

Based on the study of the structures of organisms in nature and their responsive for the environmental changing, we will develop wood-based discoloration and luminescence biomimetic intelligent materials by utilizing wood as raw materials. First, we will screen the appropriate wood and thoroughly characterize the hierarchical porous structures of the wood. We will also optimize the synthesis strategies of the organic discoloration microcapsules and inorganic luminescence rare-earth complexes. The composites will be prepared through vacuum negative pressure method and sol-gel method. The micro-/nano- structures derived from the aggregation of the active materials will be controlled by adjusting the reaction conditions such as synthesis technique and vacuum suction parameters. The effect of the micro-/nano- structures of the active materials on the discoloration and luminescence performance of the composited will be revealed. Next, the discoloration and luminescence active materials will be spontaneously integrated with wood through coupling and layer-by-layer self-assembly methods. By comparing study the discoloration and luminescence performance of the composites and the single active material-derived composites, the mechanism of the synergy effects of the active materials on the wood biomimetic of “chameleon discoloration” and “fireflies glowing”, will be clarified. We expect our study can provide some exploratory research inspiration for the highly value-added and multifunctional utilization of wood-based materials.

在对自然界中的生物体的结构与环境响应性进行深入学习研究的基础上，以木材为基础结构材料构筑木质基仿生变色发光智能材料。在对多种木材进行筛选及其层状多孔微/纳结构表征分析的基础上，优化有机变色微胶囊及无机发光稀土配合物的合成策略，借助真空负压法、溶胶凝胶法等将变色、发光单元复合于木材基底表面，并通过调控合成工艺、真空负压参数等反应条件控制活性单元在木材表面自聚集后衍生的微/纳结构，揭示复合材料表面的微/纳结构对复合材料的变色与发光性能的影响机制。采用偶联复合、层层自组装等复合策略将具有变色性能和发光性能的活性单元同时复合于木材基底表面，通过对比研究复合材料与单一活性组分衍生的材料在变色、发光等综合性能上的差异，揭示复合材料中的活性单元对木材仿生“变色龙环境变色”和“萤火虫自然发光”的协同作用机制。为木质材料的智能化、功能化开发提供探索性研究基础。

项目从木材仿生的形成机理为核心科学问题出发，以有机变色微胶囊的可控合成、木质基仿生智能复合材料微/纳结构可控构筑、复合材料构效关系与变色发光机制为主要研究内容，取得的主要创新性成果如下：采用尿素-三聚氰胺-甲醛树脂通过原位聚合法对光致变色材料进行微胶囊化。以三聚氰胺甲醛作为外壳，有机变色材料作为内核，优化复合策略，提高有机变色材料的稳定性和抗氧化性，为构筑智能仿生木材制备了关键性材料。采用滴涂法制备微胶囊化光致变色材料/聚二甲基硅氧烷木质复合材料。分析木质光致变色复合材的热稳定性、变色发光性能指标及变化规律，为建立智能仿生机理模型提供数据支撑。揭示出活性单元在木材表面的自聚集规律及其衍生微/纳结构对木质仿生复合材料变色性能的影响机制，系统阐明了木质仿生复合材料表面具有良好的光致变色性能和耐老化性能，有效提高了光致变色复合材料的疏水性能及机械性能，为开发具有感知、自驱动功能的智能型、多功能型木材仿生变色发光复合体系，建立探索性科学理论基础，为木质资源高值化开发与利用提供新的研究思路和科学依据。