Organische Derivate des Silikagels mit SiC‐Bindung II

Abstract

Organic derivatives of silica were prepared by treating silica with triphenyl‐ and trimethylchlorosilane or with hexamethyldisilazane. The trimethylsiloxy derivatives are extremely hydrophobic.

Nature and Estimation of Functional Groups on Solid Surfaces

“…Trimethylsilyl groups can also be grafted to the silica surface by reaction with hexamethyldisilazane, Me 3 Si-NH-SiMe 3 [622,623]. The reaction has an even faster rate than that with trimethylchlorosilane [624].…”

Development and characterization of polymer-grafted ceramic membranes for solvent nanofiltration

“…It is shown that crosslinking these systems results in an increase in thermal and chemical stability and prevents the polymer from excessive swelling [57,58,[83][84][85][86]. A PI membrane can be cross-linked by radical initiation, through thermal treatments, by UV irradiation [84,87] or by chemical crosslinking [57,58,[88][89][90][91]. For SRNF, radical initiation is not suitable, because crosslinking cannot be throughout the whole membrane.…”

“…Reaction with mono-, di-and trifunctional organosilanes are of particular interest. Apart from good thermal stability, such layers also resist in some extend to hydrolytic degradation, especially with increasing surface coverage [87]. Modification of a surface can be achieved either by: • • Exposing it directly to a silane vapor (vapor phase reaction).…”

Bonded stationary phases for chromatography

“…If the primary organic layer attached to the silica (such as a Porasil) is itself reactive, such as an aromatic hydrocarbon, its reactivity can in principle be used to introduce further substitution of any desired functionality and/or chain length, and therefore a wide range of chromatographic selectivities. Grignard reactions with chlorosilanes have long been known (7), and a butyl derivative of silica gel has been prepared via such a reaction (8,9). To our knowledge, however, the present work is the first to apply the reaction to the preparation of substrates for chromatography.…”