摘要
本文用CC-gA气相色谱仪测定并计算了正硅酸乙酯水解与缩合形成溶胶-凝胶的转化过程中的ROH、H2O、Si-OR、Si-OH的浓度变化.研究了温度、pH对水解与缩合反应的影响.得出了水解与编合反应机理与速率常数.发现酸性体系对水解有利而对缩合不利;且缩合反应主要是在硅醇之间进行.碱性体系对缩合有利而对水解不利;且缩合反应主要是在硅醇与硅酯之间进行.
The hydrolysis and polycondensation process of TEOS were studied by taking into measuring of ROH, HOR, Si-OR Si-OH with CC-9A Gas Chromatoraphy, and temperature, pH. The mechanism and reaction rate constants of hydrolysis and condensation on TEOS were first deduced. It was found that: 1)The hydrolyzing rate is quickened with acid as catalyst, but polycondensation rate slows down and polycondensation reaction is Si-OH+HO-S-St-O-St+H2O. 2) Polycondensation rate is quickened, hydrolying rate slows down with base as catalyst and polycondensation reaction is: St-OR+HO-Si-St-O-Si+ROH.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
1996年第4期703-707,共5页
Journal of Inorganic Materials
基金
机械部教育司基金
关键词
水解
缩合
溶胶凝胶法
硅酸乙酯
sol-gel, hydrolysis, polycondensation, silicagol