Behavior of fused silica capillaries subjected to gamma radiation. Part 1: Chromatographic performance

Abstract

SummaryFused silica capillaries deactivated with D4 and coated with OV-1 were subjected to cobalt-60 gamma radiation in order to elucidate the effect of incident radiation on column performance. The chromatographic performance of these open tubular columns in which OV-1 was polymerized in sifu was found to be dependent on the dosage of radiation and was evaluated before and after the irradiated columns were rinsed with solvent. Of the radiation dosages employed, 3 MRad produced superior chromatographic performance coupled with very favorable residual surface activity.

Columns: Packed and Capillary; Column Selection in Gas Chromatography

“…Since then, various approaches for crosslinking have been investigated. These include chemical additives such as organic peroxides (120)(121)(122)(123)(124)(125)(126)(127)(128), azo compounds (82,129,130), ozone (131), and gamma radiation (77,(132)(133)(134)(135). Several different peroxides have been evaluated; dicumyl peroxide is the most popular.…”

“…On the other hand, for freeradical initiators that are liquid at ambient temperature, the column is first coated with stationary phase, then saturated with vapors of the reagent (47,82). Gamma radiation from a 60 Co source has also been used (77,114,(132)(133)(134)(135) as an effective technique for crosslinking polysiloxanes. In a comparative study of gamma radiation with peroxides, Schomburg et al (77) noted that each approach immobilized polysiloxanes, but that the formation of polar decomposition products is avoided with radiation.…”

Aspects of High-Resolution Gas Chromatography as Applied to the Analysis of Hydrocarbon Fuels and Other Complex Organic Mixtures. Volume 1

“…Several workers have subjected these phases to liquid nitrogen temperatures without any mechanical failure of the gas flowpath. In short, the polyimide protected tubing maintains its integrity for brief intervals at -196 0 C. Research into fabricating techniques for producing bonded phase OTCs is ongoing [365][366][367][368][369][370][371][372] and indeed excellent results are being obtained from numerous procedures for crosslinking and surface attachment of the stationary phase. Some of the most desirable aspects of the bonded phase OTCs are their excellent film stability and the very low phase bleed.…”