Isotope Effect in the Separation of Polystyrene by Normal Phase and Reversed Phase Liquid Chromatography

Abstract

The retention behavior of deuterated polystyrene (d-PS) and normal hydrogenous polystyrene (h-PS) was investigated in normal phase (NP) and reversed phase (RP) liquid chromatography (LC). It was found that d-PS was retained slightly longer than h-PS in NPLC (bare silica column and tetrahydrofuran (THF)/n-hexane mixed mobile phase) while in RPLC (C18-bonded silica column and THF/methanol mixed mobile phase) h-PS was retained longer than d-PS. The retention behaviors are interpreted in terms of the thermodynamic variables associated with LC separations. The different retention behavior of deuterated polymers from that of hydrogenous polymers could allow separation of partially deuterated polymers according to the deuterium content, such as for copolymers in LC characterization.