Tang Wei, Zhang Hengyi, Hess Dennis W, Xie Chunmei, Liu Jing, Chai Xijuan, Xu Kaimeng, Zhang Lianpeng, Wan Hui, Xie Linkun
Yunnan Provincial Key Laboratory of Wood Adhesives and Glued Products, Southwest Forestry University, Kunming 650224, People's Republic of China.
College of Materials and Chemical Engineering, Southwest Forestry University, Kunming 650224, People's Republic of China.
ACS Appl Mater Interfaces. 2024 Aug 21;16(33):44077-44093. doi: 10.1021/acsami.4c09951. Epub 2024 Aug 9.
Wood, as a natural biomass material, has long been a research focus. Superhydrophobic modified wood, in particular, has shown great promise in a myriad of engineering applications such as architecture, landscape, and shipbuilding. However, commercial development has encountered significant resistance due to preparation difficulties and sometimes unsatisfactory performance. In this study, hydrophobic/superhydrophobic wood comodified with methyltrimethoxysilane (MTMS) and 1,1,2,2-perfluorodecyltrimethoxysilane (PFDTMS) was fabricated by a one-step sol-gel method that uses an growth process. Low-molecular-weight MTMS was allowed to permeate the three-dimensional porous wood interior. Then, acid-base catalysts were used to regulate the hydrolytic condensation process of MTMS and PFDTMS composite silanes to generate micro/nano hierarchical structures with low surface energy on the wood surface. The physicochemical characteristics of modified wood were investigated and the reaction mechanism established. The modified wood displayed excellent internal hydrophobicity/surface superhydrophobicity, water-moisture resistance, and dimensional stability at low fluorine concentrations. The resulting superhydrophobic surface provided stain resistance, self-cleaning ability, and loading capacity in water while exhibiting good mechanochemical stability; wood mechanical strength was also enhanced. This methodology created a superhydrophobic surface and bulk hydrophobization of wood in one step. Beyond wood, this approach is expected to provide a promising approach for functional modification of other porous composite materials.
木材作为一种天然生物质材料，长期以来一直是研究重点。特别是超疏水改性木材，在建筑、景观和造船等众多工程应用中展现出巨大潜力。然而，由于制备困难且有时性能不尽人意，其商业开发遭遇了重大阻力。在本研究中，采用一步溶胶 - 凝胶法，利用生长过程制备了用甲基三甲氧基硅烷（MTMS）和1,1,2,2 - 全氟癸基三甲氧基硅烷（PFDTMS）共改性的疏水/超疏水木材。低分子量的MTMS渗透到三维多孔木材内部。然后，使用酸碱催化剂调节MTMS和PFDTMS复合硅烷的水解缩合过程，以在木材表面生成具有低表面能的微/纳分级结构。研究了改性木材的物理化学特性并建立了反应机理。改性木材在低氟浓度下表现出优异的内部疏水性/表面超疏水性、耐水防潮性和尺寸稳定性。所得超疏水表面具有耐污性、自清洁能力和在水中的负载能力，同时展现出良好的机械化学稳定性；木材的机械强度也得到了增强。这种方法一步实现了木材超疏水表面的创建和整体疏水化。除木材外，该方法有望为其他多孔复合材料的功能改性提供一种有前景的途径。
