生物质纳米纤丝仿生定向可控制备与性能研究

According to the theory of "Integration of Structure to Function", this project aims to prepare the bundles of nanofiber with excellently high tensile strength and oriented strengthen nanocomposite with laminated structure, respectively. Through the idea from bionic, and regeneration, to controllable self-assembly, the super-length nanofibril was drawn in rotary direction as well as oriented formation. Then, starting from the formation mechanism of wood and its units of cell wall, in order to expose the relation between multiscale micro-nano structure of biomass materials and bionic structural materials, the nano-scalar self-assmble of wood cell wall is to be imitated. Next, the bionic preparation of nano structure material and spatial anisotropy of biomass nanofiber were in research, through the design from controllable preparation of oriented strengthen nanofiber as well as the structure units. Therefore, the biomass nano-structure model of "bionic representation- - self-assmbled units- - oriented lamination with super-length fiber" could be built. At last, to provide a theoretical basis of biomass material with high-valued utilization, two systems were to be presented including design and controllable preparation of oriented strengthen long nano-fiber as well as the theory of functional assembly with multi-scalar and classes of nano-structure materials.

本项目将根据复合材料结构－功能一体化的理论，通过仿生、再生、自组装可控制备的研究思路，对纤维素超长纳米纤丝进行旋转定向拉伸和定向铺装，制备具有超高抗拉强度的纤维素纳米纤维束和具有纳米纤维素定向增强的层合结构复合材料。从木材细胞壁组成单元及木材形成机理出发，效仿木材细胞壁组分纳米级的自组装方法进行仿生，揭示生物质材料多尺度微纳观结构与仿生结构材料的关系。通过生物质纳米长纤丝定向增强可控制备和定向增强纳米结构单元的设计，研究生物质纤维素纳米纤丝结构空间各向异性和纳米结构材料的宏观仿生制备方法，建立"仿生再现-纳米结构单元自组装-超长纤维定向层合"的生物质纳米结构模型。提出生物质纳米长纤丝定向增强的设计与可控制备，纳米结构材料的多尺度，多级次功能组装的理论体系，为生物质材料高值化利用提供理论依据。

本项目根据复合材料结构－功能一体化的理论，通过仿生、再生、自组装可控制备的研究思路，制备了高抗拉强度的纤维素纳米纤维束和具有纳米纤维素定向增强的层合结构复合材料，为生物质材料高值化利用提供理论依据：.1、研究内容：本项目依托前期项目“纤维增强木塑复合材料界面力学特性的研究”（31170514），根据流体力学理论和射流技术，采用湿法挤出方法，成功实现了将具有超长长径比的纳米纤维素长纤丝可控定向制备为高性能纳米纤维素定向增强的线状复合材料；仿生制备了具有木材细胞壁多层次、多孔状和各向异性结构特征的纳米纤维素纤丝增强的二维结构复合材料；利用超长纳米纤维素纤丝具有可实现网络互穿的特征，可控制备具有高回弹性的三维网络结构凝胶复合材料。.2、重要结果：将纳米纤维素纤丝与多壁碳纳米管复合，有效的解决了纳米纤维素纤丝易团聚不易分散的难题，为高效合理利用生物质纳米纤维制备高强度导电材料找到了一个很好的方法。将石墨烯与纳米纤维素纤丝进行插层复合，通过层层可控组装，实现了制备高强、高韧、高导电的线状超级电容器材料。.3、关键数据：利用湿纺纺丝法成功制备出高强度的生物质纳米纤维素/还原氧化石墨烯(CNFs/RGO)复合纤维，其拉伸强度可达338.4MPa，全固态结状超级电容器的比电容可达218mF/cm2，为利用生物质纳米材料制备可穿戴新能源材料提供了思路。.4、科学意义：本项目实现了生物质纳米纤丝仿生定向多尺度结构的可控制备；从理论上证明了生物质纳米纤丝重构具有木材细胞壁特征复合材料的可能性；从技术上实现了生物质纳米材料从解纤到纤丝重构的一体化技术和方法；为利用生物质纳米材料制备高附加值新材料提供了理论依据。