摘要
本文利用正庚醇或正辛醇与硅胶表面羟基反应制备了酯化硅胶.测定了酯化硅胶的物理结构、水蒸气吸附等温线、润湿热、差热分析和红外光谱.结果表明:(1)所有酯化硅胶的真密度(d_T)、比表面(S)和比孔体积(V)均减少,而表观密度(d_A)增加,但平均孔半径(r)变化不大;(2)酯化硅胶是憎水的,其对水蒸气吸附,以及对水和环己烷的润湿热均显著减少;(3)酯化硅胶的表面酯基在空气中于235—350℃破坏;(4)酯化反应是可逆的,硅胶表面酯基在水中大约可水解41—47％.
The esterified silica gel has been prepared by the reaction between the surface hydroxyl groups of silica gel and n-heptanol or n-octanol. The physical structure, water vapor adsorption isotherms, heat of wetting, DTA and IR for esterified silica gel were determined. The results indicate: (1) for all esterified silica gels d_T, S and F are all decreased, and d_A is increased, but r suffers only a small change; (2) the esterified silica gel is hydrophobic, it shows a remarkable decrease in water vapor adsorption, and in heat of wetting for water and cyclohexane; (3) the surface ester groups of esterified silioa gel are destroyed at 235-350℃ in air; (4) the esterification reaction is reversible and the surface ester groups of silica gels were hydrolyzed in water by about 41-47%.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1991年第5期446-450,共5页
Acta Chimica Sinica
基金
江苏省科委资助的应用基础研究项目
