Gas chromatography system constant database over an extended temperature range for nine open-tubular columns.

Affiliation

Department of Chemistry, Wayne State University, Rm 185 Chemistry, Detroit, MI 48202, USA. Electronic address: [Email]

Abstract

The solvation parameter model is used to characterize the retention properties of poly(octylmethylsiloxane), poly(dimethyldiphenylsiloxane), silphenylene-dimethylsiloxane copolymer, poly(dimethylmethyltrifluoropropylsiloxane), poly(3-cyanopropylphenyldimethylsiloxane), and poly(ethylene glycol) (SPB-Octyl, HP-5, Rxi-17, Rxi-5Sil MS, Rtx-OPP, DB-1701, DB-225, Rtx-440 and HP-INNOWAX) stationary phases over an extended temperature range from 60 °C to close to the maximum column operating temperature. System maps constructed from the system constant database are used to evaluate the influence of temperature on the contribution of intermolecular interactions to differences in selectivity. None of the stationary phases are hydrogen-bond acids. Increasing temperature reduces the contribution from cavity formation/dispersion, dipole-type interactions and hydrogen-bond basicity in a stationary phase specific manner with their preservation to the highest temperature studied for each column. Electron lone pair interactions are generally repulsive at lower temperatures becoming attractive and leading to an increase in retention at higher temperatures.

Keywords

Gas chromatography,Open-tubular columns,Selectivity,Solvation parameter model,System constants,Temperature,

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