【摘要】 为解决SiO2气凝胶质脆和硬硅钙石热导率偏高的问题,以正硅酸乙酯为硅源采用溶胶-凝胶法制备SiO2气凝胶先驱体,而后将其与硬硅钙石复合经超临界干燥制备了硅酸钙复合纳米孔超级绝热材料.采用瞬时热带法测试样品常温下1.01×105～1×10-2Pa范围内的热导率,研究了制备条件对复合材料热导率的影响.结果表明,复合材料热导率随硬硅钙石体积质量的减小以及复合增重率的增加而降低,但随气凝胶体积质量的增大先降低后升高.更多还原

【Abstract】 To solve the problems of the low strength of silica aerogel and the high thermal conductivity of xonotlite,silica sol was prepared with TEOS through sol-gel process,and then xonotlite-silica aerogel nanoporous super insulation materials dried by supercritical drying technique were prepared with silica sol compounded into xonotlite.A transient hot-apparatus was used to measure the thermal conductivity of samples at normal temperature in an environmental pressure range of 1.01×105-1×10-2 Pa,and the effect of preparation condition on the thermal conductivity of the composite materials was studied.It is indicated that the thermal conductivity of the composite materials decrease with decreasing unit weight of xonotlite and increasing composite mass growth rate,but they experience the changeable process from decrease to increase with increasing unit weight of silica aerogel.更多还原