纳米SiO_2气凝胶的表面改性与分形  

Surface Modification and Fractal Analysis of Nano SiO_2 Aerogels

作　　者：刘世明[1] 曾令可[1] 王慧[1] 

机构地区：[1]华南理工大学材料科学与工程学院,广州510640

出　　处：《材料导报》2009年第6期8-10,共3页Materials Reports

基　　金：国家自然科学基金资助项目(50676033)

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。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.

关 键 词：分形维数 改性 SIO2气凝胶 疏水性 

分 类 号：TQ127.2[化学工程—无机化工] TQ622.23