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首页> 外文期刊>Journal of Non-Crystalline Solids: A Journal Devoted to Oxide, Halide, Chalcogenide and Metallic Glasses, Amorphous Semiconductors, Non-Crystalline Films, Glass-Ceramics and Glassy Composites >Effects of progressive changes in organoalkoxysilane structure on the gelation and pore structure of templated and non-templated sol-gel materials
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Effects of progressive changes in organoalkoxysilane structure on the gelation and pore structure of templated and non-templated sol-gel materials

机译：有机烷氧基硅烷结构的逐步变化对模板化和非模板化溶胶-凝胶材料的凝胶化和孔结构的影响

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摘要

We study how progressive changes in silane structure affect the synthesis and properties of organosilicas. Tetraethoxysilane (TEOS), tetramethoxysilane (TMOS), methyltrimethoxysilane (MTMS), bis(trimethoxysilyl)ethane (BTMSE), bis(trimethoxysilyl)hexane (BTMSH), and bis(trimethoxysilylpropyl)amine (BTMSPA) are used as precursors in non-templated base and acid-catalyzed sol-gel processes, and in templated processes with cetyltrimethylammonium bromide (CTAB) and polyoxyethylene 10 lauryl ether (C12E10). The gel time of materials made without templates is mainly controlled by the structure of the silane rather than its reactivity. For instance, a dangling methyl group (MTMS) inhibits gelation, while a short bridging chain (BTMSE) promotes gelation. In basic conditions, mesoporous materials are obtained with TEOS and TMOS, while microporous materials are obtained with organically modified silanes without added amine. Dipropylamine, originally added as a catalyst, in fact templates mesopores in BTMSH-derived organosilica. In acidic conditions without pore templates, all products are microporous. In the presence of CTAB, mesopore templating occurs with TEOS. TMOS. BTMSE, and BTMSPA. With C12E10, mesopore templating occurs with TEOS, TMOS, and BTMSE. Surprisingly, the BTMSE-based material has the most uniform mesopores of all samples in the C12E10 series. Mesopore templating fails when a dangling organic limits the formation of stable pore walls (MTMS) or a large hydrophobic chain disrupts the formation surfactant micelles (BTMSH). (c) 2006 Elsevier B.V. All rights reserved.
机译：我们研究了硅烷结构的逐步变化如何影响有机硅的合成和性能。四乙氧基硅烷（TEOS），四甲氧基硅烷（TMOS），甲基三甲氧基硅烷（MTMS），双（三甲氧基硅烷基）乙烷（BTMSE），双（三甲氧基硅烷基）己烷（BTMSH）和双（三甲氧基硅烷基丙基）胺（BTMSPA）被用作非模板的前体碱和酸催化的溶胶-凝胶工艺，以及在模板工艺中使用十六烷基三甲基溴化铵（CTAB）和聚氧乙烯10月桂基醚（C12E10）。无模板制得的材料的胶凝时间主要由硅烷的结构而不是其反应性控制。例如，悬空的甲基（MTMS）抑制胶凝，而短桥连（BTMSE）促进胶凝。在碱性条件下，中孔材料是通过TEOS和TMOS获得的，而微孔材料是通过有机改性的硅烷而未添加胺获得的。最初作为催化剂添加的二丙胺实际上是在BTMSH衍生的有机二氧化硅中模板化中孔的模板。在没有孔模板的酸性条件下，所有产品都是微孔的。在存在CTAB的情况下，TEOS会产生中孔模板。 TMOS。 BTMSE和BTMSPA。对于C12E10，TEOS，TMOS和BTMSE会产生中孔模板。出乎意料的是，基于BTMSE的材料在C12E10系列的所有样品中具有最均匀的中孔。当悬挂的有机物限制了稳定孔壁（MTMS）的形成或较大的疏水链破坏了表面活性剂胶束（BTMSH）的形成时，中孔模板化失败。 （c）2006 Elsevier B.V.保留所有权利。

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