Li Lengwan, Chen Pan, Medina Lilian, Yang Lin, Nishiyama Yoshiharu, Berglund Lars A
Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, 10044 Stockholm, Sweden.
Beijing Engineering Research Centre of Cellulose and Its Derivatives, School of Materials Science and Engineering, Beijing Institute of Technology, 100081 Beijing, People's Republic of China.
ACS Nano. 2023 Aug 22;17(16):15810-15820. doi: 10.1021/acsnano.3c03664. Epub 2023 Aug 2.
Cellulose nanofibrils (CNF) with 2D silicate nanoplatelet reinforcement readily form multifunctional composites by vacuum-assisted self-assembly from hydrocolloidal mixtures. The final nanostructure is formed during drying. The crystalline nature of CNF and montmorillonite (MTM) made it possible to use synchrotron X-ray scattering (WAXS, SAXS) to monitor structural development during drying from water and from ethanol. Nanostructural changes in the CNF and MTM crystals were investigated. Changes in the out-of-plane orientation of CNF and MTM were determined. Residual drying strains previously predicted from theory were confirmed in both cellulose and MTM platelets due to capillary forces. The formation of tactoid platelet stacks could be followed. We propose that after filtration, the constituent nanoparticles in the swollen, solid gel already have a "fixed" location, although self-assembly and ordering processes take place during drying.
具有二维硅酸盐纳米片增强的纤维素纳米原纤维（CNF）通过真空辅助自组装，能轻易地从水胶体混合物中形成多功能复合材料。最终的纳米结构在干燥过程中形成。CNF和蒙脱石（MTM）的晶体性质使得利用同步加速器X射线散射（广角X射线散射、小角X射线散射）来监测从水和乙醇中干燥过程中的结构演变成为可能。研究了CNF和MTM晶体的纳米结构变化。确定了CNF和MTM面外取向的变化。由于毛细作用力，先前从理论上预测的纤维素和MTM薄片中的残余干燥应变得到了证实。可以追踪类晶体薄片堆叠的形成过程。我们认为，过滤后，肿胀的固体凝胶中的组成纳米颗粒已经有了一个“固定”位置，尽管在干燥过程中会发生自组装和有序化过程。
