Cao Min, Li Shu-Liang, Cheng Jin-Bo, Zhang Ai-Ning, Wang Yu-Zhong, Zhao Hai-Bo
The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu 610064, China.
The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials (MoE), National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan), State Key Laboratory of Polymer Materials Engineering, College of Chemistry, Sichuan University, Chengdu 610064, China.
J Hazard Mater. 2021 Feb 5;403:123977. doi: 10.1016/j.jhazmat.2020.123977. Epub 2020 Sep 16.
Elastic biomass aerogels have attracted widespread attention but are seriously hindered by environmentally unfriendly cross-linkers and fire hazards for functional applications. This study outlines the fabrication of a fully bio-based, low fire-hazard and superelastic aerogel without any cross-linkers for excellent thermal insulation and oil absorption, via creating highly oriented wave-shaped layer microstructures and subsequently depositing nonflammable siloxane coating on the surface of the aerogel skeleton. The resultant environmental-safety aerogel showed the combined advantages of anisotropic super-elasticity, hydrophobicity, low density and high flame retardancy (limiting oxygen index value of 42%, UL-94 V-0 rating, and extremely low heat release), thus leading to many benefits for solving environmental hazards. For instance, this fire-safety biomass aerogel can be used as the high-performance thermal insulator with low thermal conductivity and high shielding efficiency. The aerogel also exhibited a great selectively oil clean-up absorption with a high absorption capacity of 117 times its own weight and excellent recyclability. Especially, due to the highly oriented microstructures, the aerogel as a filter showed the fastest separation rates of oil/water mixture (flux rate of 145.78 L h g) ever reported. Such a method of preparing super-elastic biomass aerogels will provide new insights into their multifunctional applications with high environmental safety.
弹性生物质气凝胶已引起广泛关注，但在功能应用中受到环境不友好的交联剂和火灾隐患的严重阻碍。本研究概述了一种完全基于生物的、低火灾隐患且超弹性的气凝胶的制备方法，该气凝胶无需任何交联剂即可实现出色的隔热和吸油性能，通过创建高度取向的波浪形层微结构，随后在气凝胶骨架表面沉积不可燃的硅氧烷涂层。所得的环境安全气凝胶具有各向异性超弹性、疏水性、低密度和高阻燃性（极限氧指数值为42%，UL-94 V-0等级，且热释放极低）的综合优势，从而为解决环境危害带来诸多益处。例如，这种防火生物质气凝胶可作为具有低导热率和高屏蔽效率的高性能隔热材料。该气凝胶还表现出出色的选择性油污清理吸收能力，吸收容量高达自身重量的117倍，且具有出色的可回收性。特别是，由于高度取向的微结构，该气凝胶作为过滤器显示出有史以来报道的最快的油/水混合物分离速率（通量率为145.78 L h g）。这种制备超弹性生物质气凝胶的方法将为其具有高环境安全性的多功能应用提供新的见解。
