Cai Lijian, Chen Yutong, Lu Zetan, Wei Ming, Zhao Xin, Xie Yanjun, Li Jian, Xiao Shaoliang
Key Laboratory of Bio-based Material Science & Technology (Ministry of Education), Northeast Forestry University, Harbin, PR China.
Engineering Research Center of Advanced Wooden Materials (Ministry of Education), Northeast Forestry University, Harbin, PR China.
Carbohydr Polym. 2024 Apr 1;329:121765. doi: 10.1016/j.carbpol.2023.121765. Epub 2024 Jan 8.
Developing bio-based sustainable wood adhesives is significant as a substitute for petroleum-derived adhesives. However, the existing bio-based adhesives have disadvantages of complex fabrication, uncontrollable viscosity, and poor water resistance. Herein, we developed a citric acid/chitosan adhesive with viscosity-controlled and water-resistant features by one-step dissolution at room temperature based on the supramolecular self-assembly strategy. Different wood products (plywood, laminated veneer lumber and particleboard) with superior performance were prepared by applying that adhesive on veneer and wood particles (fine and rough particles). The plywood test results showed that the citric acid/chitosan adhesive had dry and wet shear strengths outperforming the China National Standard (GB/T 9846-2015, ≥0.7 MPa), reaching 2.1 and 1.1 MPa, respectively. The adhesion mechanism was mechanical interlocks and cross-linking of citric acid/chitosan in adhesives with those in the cell wall. This work provides high promise for alternatives to traditional unsustainable wood adhesives (urea-formaldehyde, melamine-urea-formaldehyde and phenolic resins) for fabricating different wood products.
开发生物基可持续木材胶粘剂作为石油衍生胶粘剂的替代品具有重要意义。然而，现有的生物基胶粘剂存在制备工艺复杂、粘度不可控和耐水性差等缺点。在此，我们基于超分子自组装策略，通过室温一步溶解法开发了一种具有粘度可控和耐水特性的柠檬酸/壳聚糖胶粘剂。通过将该胶粘剂应用于单板和木材颗粒（细颗粒和粗颗粒）制备出了性能优异的不同木制品（胶合板、单板层积材和刨花板）。胶合板测试结果表明，柠檬酸/壳聚糖胶粘剂的干、湿剪切强度均优于中国国家标准（GB/T 9846-2015，≥0.7MPa），分别达到2.1MPa和1.1MPa。其粘附机理是胶粘剂中的柠檬酸/壳聚糖与细胞壁中的柠檬酸/壳聚糖发生机械互锁和交联。这项工作为制造不同木制品的传统不可持续木材胶粘剂（脲醛、三聚氰胺-脲醛和酚醛树脂）提供了极具潜力的替代品。
