Preparation and Microstructures of Nano-porous SiO2 Thermal Insulation Materials by Freeze-casting of SiO2 in TBA/H2O Suspensions
A kind of porous SiO2 monolithic materials with pore size distributed in nano and micron scales has been fabricated by freeze-casting of SiO2 nano-size powders in TBA (tert-butyl alcohol)/H2O suspensions.The content of TBA in the well mixed TBA/H2O binary co-solvent plays an important role in size and morphology control of the pores in the obtained SiO2 monolithic materials,since the ratio of TBA/H2O determines the competition of crystallization of TBA and ice,therefore,the microstructure of the monolithic SiO2.It was found that the content of TBA in the range from 30 to 40% was suitable for formation of more nano-pores in the SiO2 monolith.The insulation materials freeze-casted from the suspension of SiO2 in 13wt% and TBA in 40wt% has the density of 0.17g/cm3,and the specific surface area of 282m2/g.The pore size has a trimodal size distribution with three mean diameters of 15nm,100nm and 4μm,respectively.
nano-porous SiO2 freeze-casting TBA/H2O mixture
Jie Tang Yufeng Chen Hailin Liu Yanli Huo Chunpeng Wang
China Building Materials Academy,Chaoyang District,Beijing,China,10024
国际会议
The Seventh China International Conference on High-Performance Ceramics (第七届先进陶瓷国际研讨会(CICC-7))
厦门
英文
315-318
2011-11-04（万方平台首次上网日期，不代表论文的发表时间）