水玻璃法SiO_2气凝胶的制备及其疏水改性  

Preparation of SiO_2 aerogel from water-glass and it's hydrophobic modification

作　　者：曹继杨 王国建[1,2] Cao Jiyang Wang Guojian(School of Materials Science and Engineering, Tongji University, Shanghai 201804 Key Laboratory of Advanced Civil Engineering Materials, Ministry of Education, Shanghai 201804)

机构地区：[1]同济大学材料科学与工程学院,上海201804 [2]同济大学先进土木工程材料教育部重点实验室,上海201804

出　　处：《化工新型材料》2016年第10期213-215,共3页New Chemical Materials

摘　　要：以水玻璃为硅源,水为溶剂,采用冷冻干燥法制备了纳米多孔SiO_2气凝胶材料。采用三甲基氯硅烷(TMCS)和六甲基二硅胺烷(HMDS)进行疏水改性,以减少样品在使用过程中的收缩和坍塌。结果表明,TMCS疏水改性SiO2气凝胶的表观密度为0.1682g/cm3,比表面积为363m2/g,HMDS疏水改性SiO_2气凝胶的表观密度为0.2536g/cm3,比表面积为336m2/g。SEM测试结果表明,所得产品具有非晶纳米介孔结构。接触角测定分析表明,TMCS疏水改性SiO2气凝胶与水的接触角为149°,表现出良好的疏水性。Nano-porous SiO2 aerogels were prepared via freeze drying method with water-glass as precursor and wa- ter as solvent. TMCS and HMDS were used as hydrophobic modifiers, so as to reduce shrinkage and collapsing of the sam- ple during the application. The results showed that the bulk density and specific surface area of TMCS modified SiO2 aero- gels were 0. 1682g/cm3 and 363m2/g, respectively. In addition, the bulk density and specific surface area of HMDS modified SiO2 aerogels were 0. 2536g/cm3 and 336m2/g, respectively. The experimental results of SEM showed that SiO2 aerogels had amorphous nano-mesoporous structure. The results of contact angle test proved that the contact angle of TMCS modi- fied SiO2 aerogels could reach 149°,so it showed good hydrophobicity.

关 键 词：SIO2气凝胶 水玻璃 真空冷冻干燥 疏水改性 

分 类 号：TQ427.26[化学工程]