Li Suiyi, Wang Haohao, Wan Zhangmin, Guo Yang, Chen Chuchu, Li Dagang, Zhu Mingwei, Chen Yanfeng
National Laboratory of Solid State Microstructures & Jiangsu Key Laboratory of Artificial Functional Materials & Department of Materials Science and Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China.
Bioproducts Institute, Departments of Chemical and Biological Engineering, Chemistry and Wood Science, The University of British Columbia, 2360 East Mall, Vancouver, BC V6T 1Z3, Canada.
ACS Appl Mater Interfaces. 2022 May 12. doi: 10.1021/acsami.2c01118.
Renewable and biodegradable natural polymeric materials are attractive candidates for replacing nonbiodegradable plastics. However, it is challenging to fabricate polysaccharide-based materials (such as cellulose and chitin) that can be used in humid or even watery environments due to their inferior stability against water. Here, a self-locking structure is constructed to develop a strong, water-resistant, and ionic conductive all-chitosan film without other additives. The densely packed self-locking structure introduces strong interactions between chitosan nanofibers, preventing the fibers from disentangling even in watery environments. The resulting film exhibits outstanding tensile strength of ∼144 MPa, superior wet strength of ∼54.3 MPa, and high ionic conductivity of 0.0012 S/cm at 10 M KCl, which are significantly higher than those of conventional polysaccharide-based materials and many commercially used plastics. Additionally, it also possesses outstanding flexibility, excellent thermal stability, good antimicrobial ability, and biodegradability, which make it a promising eco-friendly alternative to plastics for many potential applications, such as packaging bags, drinking straws, and ion regulation membranes.
可再生且可生物降解的天然高分子材料是替代不可生物降解塑料的理想选择。然而，由于多糖基材料（如纤维素和几丁质）在潮湿甚至水环境中的稳定性较差，制造可用于此类环境的材料具有挑战性。在此，构建了一种自锁结构，以开发一种无需其他添加剂的坚固、防水且具有离子导电性的全壳聚糖薄膜。密集堆积的自锁结构在壳聚糖纳米纤维之间引入了强相互作用，即使在水环境中也能防止纤维解缠。所得薄膜表现出约144 MPa的出色拉伸强度、约54.3 MPa的优异湿强度以及在10 M KCl下0.0012 S/cm的高离子电导率，显著高于传统多糖基材料和许多商业使用的塑料。此外，它还具有出色的柔韧性、优异的热稳定性、良好的抗菌能力和生物降解性，这使其成为塑料袋、吸管和离子调节膜等许多潜在应用中有望替代塑料的环保材料。
