Spectroscopic and chromatographic evaluation of cyclic siloxane bonded phases for microcolumn gas chromatography of lower hydrocarbons
✍ Scribed by Samuel O. Akapo; Jean-Marie D. Dimandja; Maria T. Matyska; Joseph J. Pesek
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 838 KB
- Volume
- 8
- Category
- Article
- ISSN
- 1040-7685
No coin nor oath required. For personal study only.
✦ Synopsis
Cyclic organosiloxanes were chemically bonded to silica gels and evaluated for possible use in microcolumn gas chromatography of light hydrocarbons in extraterrestrial atmospheres. DRIFT and solid state NMR spectroscopic studies confirmed the bonding of the siloxanes onto the silica surface. The surface concentration of the phases, which varied with the reactivity of the siloxane bond toward proton attack, were in the range of 0.31 pmol m-' for octaphenylcyclotetrasiloxane to 2.39 pmol m ~ for hexamethylcyclotrisiloxane packings. Of the five columns investigated, hexamethylcyclotrisiloxane and pentamethylcyclopentasiloxane bonded phases seem to provide good separation of the test solutes presumably due to their somewhat higher surface coverage. All the columns gave similar H vs. U curves with a shallow and flat minimum at the optimum region. The phases are thermally stable up to 300°C and allowed fast analysis of C,-C, hydrocarbons under isothermal conditions. 6 lo% John Wiley & sons, Inc