Template-Free Synthesis of Organically Modified Silica Mesoporous Thin Films for TNT Sensing

Adsorbents comprising swellable organically modified silica were characterized to optimize the adsorption of a wide range of perfluoroalkyl substances from water.

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A photorefractive organically modified silica glass with high optical gain

Nature ◽

10.1038/35040513 ◽

2000 ◽

Vol 408 (6808) ◽

pp. 64-67 ◽

Cited By ~ 98

Author(s):

Pavel Cheben ◽

Francisco del Monte ◽

Dennis J. Worsfold ◽

Dave J. Carlsson ◽

Chander P. Grover ◽

...

Keyword(s):

Silica Glass ◽

Optical Gain ◽

Modified Silica ◽

Organically Modified ◽

Organically Modified Silica

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Organically Modified Silica-Based Xerogels Derived from 3-Aminopropyltrimethoxysilane and 3-Isocyanatepropyltriethoxysilane through Carboxylic Acid Solvolysis

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.108 ◽

2006 ◽

Vol 514-516 ◽

pp. 108-112 ◽

Cited By ~ 2

Author(s):

Lianshe Fu ◽

Rute A. Sá Ferreira ◽

Sonia S. Nobre ◽

Luís D. Carlos ◽

João Rocha

Keyword(s):

Acetic Acid ◽

Carboxylic Acid ◽

Valeric Acid ◽

Silica Xerogels ◽

X Ray Diffraction ◽

Modified Silica ◽

13C Nuclear Magnetic Resonance ◽

Organically Modified ◽

Cross Links ◽

Organically Modified Silica

Organically-modified silica xerogels from 3-aminopropyltrimethoxysilane (APTES) and 3-isocyanatepropyltriethoxysilane (ICPTES) have been synthesized through carboxylic acid (formic acid, acetic acid and valeric acid) solvolysis. The resulting hybrid materials have been characterized by powder X-ray diffraction, mid-infrared spectroscopy, 29Si and 13C nuclear magnetic resonance, and photoluminescence spectroscopy. The results show that urea cross-links have been formed in these hybrids. The luminescence features depend on the selected carboxylic acids. For example, comparatively to the hybrids derived from formic and acetic acid solvolysis, valeric acid shows a red-shift of the emission features.

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Cross-Condensation Reactions in an Organically Modified Silica Sol-Gel

MRS Proceedings ◽

10.1557/proc-346-979 ◽

1994 ◽

Vol 346 ◽

Cited By ~ 8

Author(s):

S. Prabakar ◽

R. A. Assink ◽

N. K. Raman ◽

C. J. Brinker

Keyword(s):

Experimental Error ◽

Molecular Level ◽

Sol Gel ◽

Resonance Assignments ◽

Silica Sol ◽

Modified Silica ◽

Organically Modified ◽

Organically Modified Silica ◽

Acid Catalyzed ◽

Hydrolysis Of

ABSTRACTHigh resolution 29Si NMR has been used to study the extent of cross condensation taking place in a hybrid organic/inorganic sol-gel system. Tetraethoxysilane (TEOS) and methyltriethoxysilane (MTEOS) sol-gels were chosen for this purpose. The sols were prepared by acid catalyzed hydrolysis of TEOS and MTEOS with a H2O/Si ratio of 0.3. 29Si NMR shows signals due to both self-condensation and cross-condensation between TEOS and MTEOS. Resonance assignments were made by comparing the positions and intensities of peaks in the spectra of single and multicomponent systems. It was found that, within experimental error, the self- and cross-condensation rates are equal and that extensive molecular level mixing takes place during the early stages of the reaction.

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