The gas chromatographic separation of isomeric 1- and 2-substituted naphthalenes on liquid crystals as stationary phases

Use of a nematic liquid crystal for gas-liquid chromatographic separation of polyaromatic hydrocarbons

“…Concentration: About 0.1 µ of each component except for naphthacene, which was less, but undetermined the nematic liquid phase. The same behavior was essentially reported by Kelker and his coworkers (29) and by Chiavari and Pastorelli (23), who studied other substituted naphthalenes.…”

“…Furthermore, its well-defined chemical structure and its inherent capabilities for participation in -type charge transfer interactions should render it useful for the evaluation of such operative forces in solutions. Either other nematic liquid crystals are too volatile for this purpose, (22,23,26) or other polymeric liquid phases previously employed for PAH separations are of poorly defined composition (12, 14, 16, 28).…”

“…It has been recognized, on the other hand, that excellent separations of rigid molecules can be achieved using nematic liquid crystals as liquid phases, which exhibit an ordered molecular arrangement within a defined temperature interval (22)(23)(24)(25). This work reports base-line separations for a wide range of PAH compounds, including the socalled "benzpyrene fraction," and describes the chromatographic behavior of some PAH positional isomer pairs on such a liquid crystal stationary phase over a temperature range of 185-265 °C.…”

Historical Development of Liquid Crystalline Stationary Phases: An Overview

“…Mainly, separations are yielded based on variations in molecular shape (length-to-breadth ratio and planarity) independently on any specific interactions [29][30][31][32].…”