期刊
CHEMISTRY OF MATERIALS
卷 17, 期 16, 页码 4262-4271出版社
AMER CHEMICAL SOC
DOI: 10.1021/cm048483j
关键词
-
Silica monoliths exhibiting a unique hierarchical network structure with a bimodal pore size distribution and high surface areas were prepared from three different glycol-modified silanes by sol-gel processing. Tetrakis(2-hydroxyethyl)-, tetrakis(2-hydroxypropyl)-, and tetrakis(2,3-dihydroxypropyl)orthosilicate were obtained by transesterification reaction from tetraethylorthosilicate and the corresponding alcohols. The present work shows that, for ethylene glycol- and propane- 1, 2 -diol- modified silanes, simply the release of the corresponding diols during sol-gel processing in the presence of block copolymeric surfactants such as Pluronic P123 results in phase separation on different levels. In addition to an extraordinary cellular network structure with interconnected macropores of several hundreds of nanometers in diameter, the material exhibits a well-ordered mesostructure with periodically arranged mesopores of about 6-7 nm in diameter. Interestingly, the application of glycerol-modified silanes at the given synthesis conditions results in the formation of a disordered silica mesostructure. The architectural properties and the morphology of the gel network cannot only be controlled by the choice of the glycol but also by the amount of acid catalyst in the starting composition.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据