SiO_2气凝胶微球及其性能研究  

Preparation and Properties of Silica Aerogel Microspheres

作　　者：刘霄昱 陈琦峰[1] 黄智明[1] 王慧[1] 曾令可[1] Liu Xiaoyu;Chen Qifeng;Huang Zhiming;Wang Hui;Zeng Lingke(Department of Materials Science and Engineering, South China University of Technology, Guangzhou, 510640)

机构地区：[1]华南理工大学材料科学与工程学院,广州510640

出　　处：《陶瓷》2018年第6期27-33,共7页Ceramics

基　　金：广东省产学研项目(项目编号:B2014B090903003)

摘　　要：气凝胶是一种由纳米粒子所组成的多孔网络结构,其孔隙率可以高达85%~95%,同时在网络中充满气态分散介质的固体材料。由于其独特的结构使得气凝胶具有高比表面积、低密度、低热导率等特点,而这些特点使其在热学、声学、催化科学方面有着广泛的应用。笔者以硅溶胶为原料,采用乳液成球法与溶胶凝胶法相结合,通过常压干燥的方法制备出了SiO_2气凝胶微球,采用了扫描电镜、傅里叶红外光谱和BET等测试对所制备的SiO_2气凝胶微球的形貌和性能进行了分析。实验所制备出的SiO2气凝胶微球属于非晶体,具有亲水性,其粒径分布在5~20μm,该方法所制备的气凝胶比表面积较小,最大为451m2/g,孔分布集中在20~40nm。Aerogels are a kind of solid materials which consist of nanoparticles and have continuous network structure filling with gaseous dispersive medium,the porosity can be as high as 85%～95%.Because of its unique structure makes the aerogel has a high specific surface area,low density,low thermal conductivity and other characteristics,which makes it widely used in the fields of thermal,acoustics and catalysis science.Silica aerogel microspheres based on alkaline silica sol were synthesized using the emulsion method,sol-gel polymerization and ambient pressure drying.There morphology and physical properties were analyzed by using scanning electron microscopy（SEM）,Fourier transform infrared spectroscopy（FTIR）and the Brunauer-Emmett-Teller（BET）method.The result shows that the silica aerogel microspheres prepared by the experiment are amorphous form and hydrophobic,and the particle size distribution is between 5～20μm.The specific surface area of the aerogel prepared by this method is small,the maximum is 451 m^2/g,pore size distribution concentrated in 20～40 nm.

关 键 词：气凝胶 微球 乳液法 

分 类 号：TQ174.75[化学工程—陶瓷工业]