How to prepare reproducible, homogeneous, and hydrolytically stable aminosilane-derived layers on silica.
How to prepare reproducible, homogeneous, and hydrolytically stable aminosilane-derived layers on silica.
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DOI：
10.1021/la203638g
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发表时间：
2012-01-10
期刊：
影响因子：
--
通讯作者：
Chen W
中科院分区：
文献类型：
--
作者：
Zhu M;Lerum MZ;Chen W
评估了5种官能硅烷，3-氨丙基三乙氧基硅烷（APTES）、3-氨丙基三甲氧基硅烷（APTMS）、N-（2-氨乙基）-3-氨丙基三乙氧基硅烷（AEAPTES）和N-（2-氨乙基）-3-氨丙基三甲氧基硅烷（AEAPTMS）和N-（6-氨己基）氨甲基三乙氧基硅烷（AHAMTES）用于制备水解稳定的胺官能化二氧化硅基底。根据胺官能团与硅中心的分子内配位能力，这些可分为三组（G1、G2和G3）。硅烷化在无水甲苯中以及在升高的温度下在气相中进行。在溶液中制备的氨基硅烷衍生的层在性质上是多层的，并且在气相中产生的那些具有单层特性。一般来说，气相反应对湿度和试剂纯度的变化不太敏感，比溶液相方法更实用，并且产生更可重复的结果。分子内催化胺功能被发现是重要的硅烷化和水解。G1硅烷（APTES和APTMS）中的伯胺基团可以容易地催化硅氧烷键的形成和水解，使其硅烷层对水解不稳定。G3硅烷（AHAMTES）中的胺官能团不能进行硅烷化的分子内催化，使得硅烷分子和表面硅烷醇之间不容易形成稳定的硅氧烷键。另一方面，G2硅烷（AEAPTES和AEAPTMS）中的仲胺基团可以催化硅氧烷键的形成，但键分离的分子内催化是空间位阻的。G2硅烷是制备稳定的胺官能化表面的最佳候选物。在两种G2氨基硅烷之间，由于AEAPTES对反应体系中水含量的敏感性较低，因此在气相中AEAPTMS比AEAPTMS产生更可再现的硅烷层。
Five functional silanes, 3-aminopropyltriethoxysilane (APTES), 3-aminopropyltrimethoxysilane (APTMS), N-(2-aminoethyl)-3-aminopropyltriethoxysilane (AEAPTES), and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (AEAPTMS), and N-(6-aminohexyl)aminomethyltriethoxysilane (AHAMTES) were assessed for the preparation of hydrolytically stable amine-functionalized silica substrates. These can be categorized into three groups (G1, G2, and G3) based on the intra-molecular coordinating ability of the amine functionality to the silicon center. Silanizations were carried out in anhydrous toluene as well as in the vapor phase at elevated temperatures. Aminosilane-derived layers prepared in solution are multilayers in nature and those produced in the vapor phase have monolayer characteristics. In general, vapor-phase reactions are much less sensitive to variations in humidity and reagent purity, are more practical than solution-phase method, and generate more reproducible results. Intra-molecular catalysis by the amine functionality is found to be important for both silanizaton and hydrolysis. The primary amine group in the G1 silanes (APTES and APTMS) can readily catalyze siloxane bond formation and hydrolysis to render their silane layers unstable toward hydrolysis. The amine functionality in the G3 silane (AHAMTES) is incapable of intra-molecular catalysis of silanization so that stable siloxane bonds between the silane molecules and surface silanols do not form easily. The secondary amine group in the G2 silanes (AEAPTES and AEAPTMS), on the other hand, can catalyze siloxane bond formation, but the intra-molecular catalysis of bond detachment is sterically hindered. The G2 silanes are the best candidates for preparing stable amine-functionalized surfaces. Between the two G2 aminosilanes, AEAPTES results in more reproducible silane layers than AEAPTMS in the vapor phase due to its lower sensitivity to water content in the reaction systems.
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影响因子：
9.9
作者：
Metwalli, E.;Haines, D.;Pantano, C. G.
通讯作者：
Pantano, C. G.
影响因子：
3.9
作者：
Pasternack, Robert M.;Amy, Sandrine Rivillon;Chabal, Yves J.
通讯作者：
Chabal, Yves J.
影响因子：
3.9
作者：
Kim, Joonyeong;Holinga, George J.;Somorjai, Gabor A.
通讯作者：
Somorjai, Gabor A.
DOI：
10.1021/i360030a002
发表时间：
1969-01-01
期刊：
INDUSTRIAL & ENGINEERING CHEMISTRY PRODUCT RESEARCH AND DEVELOPMENT
影响因子：
--
作者：
ZISMAN, WA
通讯作者：
ZISMAN, WA
影响因子：
3.9
作者：
Chen, Chi-Fan;Tzeng, Shien-Der;Gwo, Shangjr
通讯作者：
Gwo, Shangjr