摘要
基于可持续发展的需求,生物聚合物因成本低廉、绿色可再生、易于功能化等优点而受到极大关注。由生物聚合物构筑的气凝胶还具有气凝胶材料的低密度、低热导率、高孔隙率、高比表面积等优点,近10年来得到了迅速的发展,成为国际前沿热点研究方向。生物聚合物需要先形成均匀的料液体系才能进一步凝胶、干燥得到气凝胶,而构筑的气凝胶材料也需要提高其结构稳定性和多功能化才能实现进一步的应用。因此,前期的研究主要集中于制备过程的优化和应用领域的拓展两方面。除了少数可以通过调节pH或温度来进行溶解/分散外,大多数生物聚合物需要采用极性溶剂或离子液体来破坏氢键网络实现溶解/分散;随后的凝胶化可以通过氢键交联、化学共价键交联、离子交联和低温诱导等实现;湿凝胶的干燥则有超临界干燥、冷冻干燥和常压干燥;进一步,可以通过疏水改性、化学改性、复合化、衍生碳化等方法实现生物聚合物气凝胶多功能化,进而拓展其应用领域。目前,生物聚合物气凝胶材料在生物医药材料、重金属离子吸附、油水分离、隔热保温、电磁微波吸收等领域都发挥了重要的作用。本文从生物聚合物气凝胶的制备体系入手,综述了生物聚合物的溶解体系、凝胶化过程、干燥方法和功能化改性等,同时对生物聚合物气凝胶的应用和发展历程进行了介绍,进一步对其未来应用前景进行了展望,为开发生物聚合物气凝胶的研究者们提供参考。
On the basis of sustainable development,biopolymers have attracted great attention because of their low cost,regeneration potential and easy functionalization,etc.Aerogels constructed of biopolymers combine the advantages of low density,high porosity,low thermal conductivity and high specific surface area,which have become a hot research topic and made tremendous progress in the past decade.Generally,a uniform liquid system(solutions/slurries)of biopolymer is required,prior to the gelation and drying to obtain aerogels.The structural stability and the multifunctionality of assembled biopolymer aerogels need to be enhanced before their advanced applications.Therefore,previous studies mainly focus on the optimization of the preparation of biopolymer aerogels and expanding their applications.A few biopolymers can be dissolved/dispersed by adjusting pH or temperature.Typically,polar solvents or ionic liquids are adopted to break the hydrogen bonding networks of biopolymers to form uniform liquid systems.Several gelation methods,such as hydrogen bond crosslinking,covalent crosslinking,ionic crosslinking and/or low temperature induced gelation,are applied to construct the liquid system into wet gels.The aerogels are obtained through drying the as-prepared wet gels using supercritical drying,freezing drying or ambient pressure drying.The biopolymer aerogels are further multifunctionalized by hydrophobic modification,chemical modification,compositing or derivative carbonization,in order to expand the areas of their application.Biopolymer aerogels have been widely used in biomedicine materials,heavy metal ion adsorption,oil-water separation,thermal insulation,electromagnetic microwave absorption and other fields.In this paper,we review the preparation methods of biopolymer aerogels,and outline their dissolution system,gelation process,drying me-thods and functional modifications.Meanwhile,we summarize the applications and developments of biopolymer aerogels,and provide perspectives on their potential applications for future scientific research on biopolymer aerogels.
作者
肖维新
袁静
严开祺
张敬杰
XIAO Weixin;YUAN Jing;YAN Kaiqi;ZHANG Jingjie(State Key Laboratory of Technologies in Space Cryogenic Propellants,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;School of Chemical Sciences,University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2022年第20期239-248,共10页
Materials Reports
基金
中国科学院青年创新促进会项目(2019029)
中国科学院战略性先导科技专项(A类)(XDA22010201)
国家重点研发计划(2016YFC0304501,2019YFC0311401)
航天低温推进剂技术国家重点实验室开放研究课题(SKLTSCP1904)。
关键词
生物聚合物
气凝胶
生物医药材料
重金属离子吸附剂
油水分离
隔热
微波吸收
biopolymer
aerogel
biomedical material
metal ion absorbent
oil-water separation
thermal insulation
microwave absorption
