摘 要:气凝胶是一种由纳米粒子相互聚结构成的多孔性固态材料，具有密度低，孔隙率高，孔分布均匀，透光性能好等优点。因而在超低密度耐高温材料，高效高能电极，声阻抗耦合材料，高效催化剂及其载体，吸附剂等方面具有非常广阔的应用前景。
本文以正硅酸乙醋(TEOS)为原料，采用溶胶——凝胶(Sol-Gel)法制备了SiO2小球，将所得的湿凝胶经非超临界干燥技术，最终得到气凝胶小球。两种方法制得的气凝胶小球均为表面光滑的乳白色轻质固体，大小均匀，直径分别可控制在300-700nm的微球和1-5mm之间的小球，非超临界干燥工艺其直径的收缩率可稳定在30%左右。
此外本文在成功制备出SiO2 气凝胶小球的基础上通过通过溶胶——凝胶技术和非超临界干燥技术又成功的制备出了TiO2 ---- SiO2 气凝胶小球。并把制得的TiO2 ---- SiO2 二元气凝胶小球用于酯化反应中，实现了复合二元气凝胶的小球的催化作用。
关键词：TiO2 ---- SiO2 二元气凝胶小球 溶胶-凝胶 烃氨法 酯化反应 催化
Abstract:The airgel is a nanoparticles mutual polyethylene structure into the porous solid material having a low density, high porosity, uniform pore size distribution, good light transmission properties, etc.. Thus in ultra-low-density high-temperature materials, energy efficient, electrodes, acoustic impedance coupling materials, efficient catalyst and its carrier, adsorbent has a very broad application prospects.
In this paper, the positive silicic acid ethyl ester (TEOS) as raw materials by sol - gel (Sol-Gel) the prepared SiO2 ball, the wet gel obtained by supercritical drying, the resulting airgelball. The airgel obtained pellets of the two methods are the smooth surface of the milky white light solid, uniform size, diameter, respectively, can be controlled in the 300-700nm microspheres and 1-5mm between the small balls, non-supercritical drying process the shrinkage of its diameter can be stabilized at about 30%.
Addition, by in SiO2 airgel ball successfully prepared based on sol - gel technology and non-supercritical drying technology successfully prepared silica airgel TiO2 ---- ball. The prepared TiO2 ---- SiO2 binary airgel pellets used in the esterification reaction, the catalytic composite binary airgel ball.
Keywords: TiO2—SiO2 binary airgel ball sol - gel hydrocarbons ammonia catalyzed esterification reacti
