【摘要】 为解决SiO2气凝胶质脆的难题,以正硅酸乙酯为硅源,采用溶胶-凝胶法和超临界干燥工艺制备了硅酸铝纤维增强纳米孔超级绝热材料,容重为74～189 kg.m-3,并采用瞬时热带法和BET法分别测试了样品的热导率和孔径分布。结果表明,常温常压热导率为25.3～30.5 mW.(m.K)-1,103 kg.m-3典型样品723 K时的热导率为93.78 mW.(m.K)-1,孔径主要集中在10～20 nm,并且与SiO2气凝胶相比具有一定的强度,因而可用于工程实际,必将拥有广阔的应用前景。更多还原

【Abstract】 To solve the low strength problem of silica aerogel,the nanoporous super insulation materials,reinforced with aluminum silicate fiber,were prepared from TEOS through sol-gel process and supercritical drying technology.Their bulk densities were 74-189 kg·m-3,and their thermal conductivity and pore diameter distribution were measured by using the transient hot-strip and BET methods respectively.The test results indicated that their thermal conductivity is 25.3-30.5 mW·(m·K)-1 at normal temperature and pressure,the thermal conductivity of the typical sample(103 kg·m-3) is 93.78 mW·(m·K)-1 at 723K and the pore diameter of it is mainly in the range of 10-20 nm.Additionally,these materials have adequate strength compared with silica aerogel,so they can be used in project and have wide application.更多还原