In:
MRS Proceedings, Springer Science and Business Media LLC, Vol. 576 ( 1999)
Abstract:
Organically modified silicates have been prepared, using methyltriethoxysilane and tetraethoxysilane in various molar ratios. The final network is thus composed of trifunctionnal T units and tetrafunctionnal Q units. Three types of oxo bridges can be formed through the competitive self-condensation or co-condensation reactions : (T)-O-(T), (Q)-O-(Q) and (T)-O-(Q). 17 O-enriched water was used as reactant in order to selectively enrich the various oxo bridges, and to perform 17 O solid state MAS-NMR. The combination of MAS experiments recorded at two different magnetic fields, and of the recently discovered MQ-MAS experiments allowed us to identify clearly the three types of oxo bridges. Quantitative analysis was extracted from the MAS-NMR spectra, and compared with calculations based on randomly distributed Si units.
Type of Medium:
Online Resource
ISSN:
0272-9172
,
1946-4274
Language:
English
Publisher:
Springer Science and Business Media LLC
Publication Date:
1999
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