摘要：选择经典的Stöber二氧化硅为代表性样品, 采用热红联用技术 (TG-DSC-FTIR) 分析不同溶剂洗涤 (水和乙醇) 、不同温度干燥的Stöber二氧化硅样品, 探讨表面羟基、乙氧基随后处理条件的变化规律。结果表明:水洗能水解表面的乙氧基而形成羟基, 乙醇洗涤通过酯化作用使表面羟基转化为乙氧基;NH₃对Stöber二氧化硅孔内外乙醇与羟基的酯化过程具有显著的催化作用, NH₃存在时在50℃较低温度下干燥也能促进乙氧基的形成。

关键词：Stöber二氧化硅；后处理；酯化

Abstract：The classical Stöber silica was selected as representative samples, which were washed with different solvents (water and ethanol) , dried at different temperatures and then analyzed systematically by TG-DSC-FTIR. The variation of surfacehydroxyl and ethoxyl groups with post-treatments were investigated. The results demonstrate that water washing can hydrolyze ethoxyl groups into hydroxyl groups and ethanol washing can convert surface hydroxyls into ethoxyl groups by esterification. Ammonia can remarkably catalyze the esterification between ethanol and surface hydroxyls inside and outside of Stöber silica pores. Even with the relatively low temperature of 50 ℃ drying, ammonia is still able to promote the formation of ethoxyl groups.

Keywords：Stöber silica；post-treatment；esterification