Tetramethoxy silane

The sol-gel process involves hydrolysis of alkoxide precursors under acidic or basic conditions, followed by condensation and polycondensation of the hydroxylated units, which lead to the formation of porous gel. Typically a low molecular weight metal alkoxide precursor molecule such as tetramethoxy silane (TMOS) or tetra ethoxysilane (TEOS) is hydrolyzed first in the presence of water, acid catalyst, and mutual solvent... 

The initial silica sol consisted of 11 ml of tetramethoxy silane (TMOS), 5 mL of distilled water, and 1 drop of 12 N HC1. A monophasic solution was prepared by the sonogel method 9). Under continuous sonication, a total of 30 ml of tetraethoxy silane (TEOS), 7.5 mL of distilled H2O, and 11 mL of TMOS were addded in a dropwise fashion to form the precursor solution. The final silica sol was composed of a 1 1 5 mole ratio of TEOS TMOS H2O. The acid catalyst was present as a... 

See Tetramethoxy silane Metal hexafluorides Trimethylsilyl azide... 

Tetramethoxy-silan setzt sich analog den Dialkylphosphiten (s.S. 669) mit Carbonsau-ren zu Methylestern um, wobei die Ester direkt durch Destination aus dem Reaktionsge-misch isoliert werden konnen67. Die Tetraalkoxy-silane konnen auch in situ aus Silicium(IV)-chlorid mit Alkohol im Molverhaltnis 1 4 erzeugt werden. Nach diesem Ver-fahren erhalt man u.a. ... 

Silica monoliths are prepared by sol-gel technology starting from alkoxide precursors, such as tetraethoxy-silane or tetramethoxy-silane [23]. The structure of a silica monolith is characterized by an interconnected silica skeleton and bimodal distribution of 1-3-pm macropores (flow through pores) and 10-20 nm mesopores. 

Methyl silicate (tetramethoxy silane [CAS 681-84-5)) Highly reactive corrosive upon direct contact severe bums and loss of vision may result. Vapors extremely Irritating to eyes and respiratory tract severe eye bums and pulmonary edema may result. 1 ppm ERPG-2 10 ppm ERPG-3 20 ppm Coloriess crystals. Reacts vdth water, forming silicic acid and mefhanol. 

They are negative with one exception, the value for tetramethoxy-silane being positive. 

The effect of aging temperature on pore-size distribution was clearly illustrated by Yamane and Okano [25] for a gel made from tetramethoxy-silane (TMOS). As shown in Fig. 9, the porosity and average pore size... 

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