【摘要】 气凝胶是将凝胶中的溶剂或水分被除去后,其空间网状结构的介质变为气体,外表呈固体状的一类材料。它们具有超低密度、均一纳米级孔径、高孔隙率和高比表面积的特性,同时又融入了自身优异性能,是一类具有广阔发展前景的功能材料。纤维素作为地球上储量最大的多糖大分子,具有安全、稳定、无毒、可生物降解等优点。以纤维素为基体的气凝胶除具备传统气凝胶的结构特征和优势外,通过结构设计或复合改性可构建为各种高性能材料。本文主要介绍近年来纤维素基气凝胶的制备方法及各种功能改性。着眼催化、电磁、隔热、医用、分离纯化等方面的应用,综述纤维素基气凝胶的构建及最新研究进展,并针对纤维素基气凝胶在材料构建中的问题及应用前景进行了展望。更多还原

【Abstract】 Aerogels is a type of intriguing material prepared by replacing the liquid solvent in a gel with air without substantially altering the network structure or the volume of the gel body. These materials have porous structure with high porosity, low-density, high specific surface area, low dielectric permittivity and extraordinarily low thermal conductivity. Cellulose as a biodegradable polysaccharide is the most abundant biopolymer on plants. Cellulose has gainedinteresting research because it safe, stable, nontoxic, biodegradable, renewable, low cost. Cellulose aerogel as the new generation of materials promise not only a very low density as typical for aerogels but also a comparatively high strength and ductility compared with inorganic or polymeric aerogels. This paper introduced the preparation and drying technologies of cellulose aerogels. More applicationsare evolving as the scientific and engineering community becomes familiar with the unusual and exceptional physicalproperties of cellulose aerogels, focusing on catalysis, electromagnetism, heat insulation, biomedical application and purification. Moreover, the current problems and future development about cellulose-based aerogel were also mentioned.更多还原