- Simultaneous deactivation and coating of porous silica particles for microcolumn supercritical fluid chromatography
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A new method for the simultaneous deactivation and coating of porous silica particles for supercritical fluid chromatography (SFC) has been developed. This method is based on a dehydrocondensation reaction between polymeric silicon hydride reagents and the siianol groups on the surface of the particles. The procedure produces a less active surface than conventional silica packings, which results in less adsorption and Improved peak shapes for polar analytes. In SFC, more polar analytes can be chromatographed without the need for mobile phase modifiers. Furthermore, the sensitive and universal flame lonization detector (FID) can be used, since modifiers are not necessary. To avoid splitting of the column effluent before FID detection, packed capillary columns were utilized in this study. The ability to use packed capillary columns for the analysis of polar compounds, while at the same time allowing the use of a wide range of detection methods, serves to expand the number of useful applications for packed column SFC.
- Payne, Kent M.,Tarbet, Bryon J.,Bradshaw, Jerald S.,Markides, Karin E.,Lee, Milton L.
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- PROCESS FOR THE STEPWISE SYNTHESIS OF SILAHYDROCARBONS
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The invention relates to a process for the stepwise synthesis of silahydrocarbons bearing up to four different organyl substituents at the silicon atom, wherein the process includes at least one step a) of producing a bifunctional hydridochlorosilane by a redistribution reaction, selective chlorination of hydridosilanes with an ether/HCI reagent, or by selective chlorination of hydridosilanes with SiCI4, at least one step b) of submitting a bifunctional hydridochloromonosilane to a hydrosilylation reaction, at least one step c) of hydrogenation of a chloromonosilane, and a step d) in which a silahydrocarbon compound is obtained in a hydrosilylation reaction.
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Page/Page column 63; 85; 86
(2021/12/08)
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- Process for preparing alkylhydrogenchlorosilanes
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Alkylhydrogenchlorosilanes of formula I: wherein R are identical or different alkyl radicals, x is 1 or 2 and y is 1 or 2 and the sum of x and y is equal to 3, are prepared by comproportionating alkylchlorosilanes of formula II: wherein R denotes identical or different alkyl radicals, a is 1 or 2 and n is 2 or 3 and the sum of a and n is equal to 4 with hydrogenchlorosilanes of formula III: wherein R denotes identical or different alkyl radicals, b is 0, 1, 2 or 3 and c is 1, 2, 3 or 4 and the sum of b and c is equal to or smaller than 4, in the presence of a catalyst saturated with a hydrogen halide.
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- The Addition Rates of Dichloro- and Trichlorosilane to 2-Pentene and 1-Octene
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When mixtures of dichloro- and trichlorosilane were added to 2-pentene and 1-octene in the presence of a solution of chloroplatinic acid, dichloro-silane added much more rapidly than trichlorosilane.But when each silane was added separately under identical conditions, trichlorosilane added much more rapidly than dichlorosilane to the same olefins.
- Benkeser, Robert A.,Muench, Wayne C.
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