摘要
稀Na2SiO3溶液经过阳离子交换树脂除去Na+离子后,经碱化浓缩制成质量分数约为25％-30％的二氧化硅溶胶,添加化学添加剂丙三醇后加入乙酸乙脂,搅拌水解使溶胶的pH值适当降低,聚乙烯醇能使二氧化硅溶胶具有网状结构,易于成膜。薄膜在750-850℃下热处理后孔径分布在100-300 nm之间。二氧化硅薄膜在热处理过程中的微结构衍化过程可通过调节二氧化硅溶胶的pH值、添加化学添加剂和热处理温度加以控制。讨论了纳米二氧化硅胶粒溶胶的形成和形成的二氧化硅溶胶先体的成膜化学机理,并对制备的多孔二氧化硅薄膜的微结构,形貌变化和相关的物理性能进行了表征。
25%-30% colloidal silica sol was prepared from a diluted Na2SiO3 solution through removing Na + ions with positive ion exchange resin column, then concentrating under basic conditions. The pH value of the colloidal silica sol was decreased properly by adding chemical additive glycerol and then CH3COOC2H5 under stirring. Poly (vinylalcohol) (PVA) was used to make the colloidal silica sol with polymerized structure. The silica films that had average porous size of 100-300 nm were fabricated by spin-coating in 100 class clear room after being annealed at 750-850℃ for 30 min. The microstructure evolution of the silica films was controlled by adjusting the pH value of the silica sol, chemical additives and the thermal annealing temperature. The microstructure, morphology and corresponding physical properties of the microporous silica films are characterized and the chemical mechanisms of preparing colloidal silica sol and colloidal silica sol filming are discussed.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2002年第6期766-770,共5页
Journal of The Chinese Ceramic Society
基金
国家863项目(715002-0250)。
