中文摘要：

采用正丁醇、正己烷、三甲基氯硅烷（TMcs）的混合溶液对SiO2醇凝胶进行表面改性，其中TMCS比例分别为1％、3％、6％、8％、10％，采用傅立叶红外光谱（IR）进行测试。结果表明，TMCS的比例为3％时，改性效果相对较好。N2吸附-脱附实验测试结果为比表面积高达838．57m2／g，孔半径主要分布在3．6～5．2nm，存在小于2nm的微孔，并根据实验数据采用FHH模型法计算得到SiO2气凝胶的表面分形维数Ds=2．4665。

英文摘要：

Surface of nano SiO2 aerogels are modified by admixture of n-butyl alcohol, n-hexane and ehlorotrimethylsilane（TMCS）. The ratio of TMCS respectively is 1%, 3%, 6 0%, 8% and 10%. The results of Fourier transform infrared spectroscopy（IR） test show that the modification effect is better than others as the TMCS ratio is 3 %.The results of N2 adsorption-desorption test is that the specific surface area is up to 838. 57m2/g, half pore radius mainly distributes from 3. 6nm to 5.2nm, the micropore less than 2nm exists. According to the data of absorption-desorption experiment, the surface fractal dimension of silica aerogels is calculated by Frekel-Halsey-Hill（FHH） model. The surface fractal dimension of silica aerogels is 2. 4665.