title: Solvent and temperature gradients in separation of synthetic oxyethylene-oxypropylene block (co)polymers using high-temperature liquid chromatography.
abstract: Chromatographic behavior of synthetic block (co)oligomer samples (EO)n(PO)m(EO)n and (PO)n(EO)m(PO)n with different distribution of propylene oxide (PO) and ethylene oxide (EO) monomer units was investigated on three types of stationary phases on zirconium dioxide support: Zr-PS (polystyrene), Zr-carbon, and Zr-carbon C18. The effects of the distribution and sequence of the oxyethylene and oxypropylene monomer units on the chromatographic retention depend on the type of the stationary phase, but are strongly affected by the organic modifier (methanol or ACN) in aqueous-organic mobile phase. Special attention was focused on the influence of the mobile-phase composition on the separation according to the EO and PO distribution. Zirconia-based columns are stable at elevated temperatures and can be used in high-temperature LC (HTLC); hence, we investigated the temperature effects on the chromatographic behavior up to 90 degrees C. The applications of solvent and temperature gradients were compared on the zirconia stationary phases in the RP mode.
authors.affiliation: Department of Environmental Chemistry and Ecoanalytics, Faculty of Chemistry, Nicholas Copernicus University, Torun, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Welerowicz
authors.forename: Pavel
authors.initials: P
authors.lastname: Jandera
authors.forename: Katerina
authors.initials: K
authors.lastname: Novotná
authors.forename: Boguslaw
authors.initials: B
authors.lastname: Buszewski
mesh_terms: D002244:Carbon / Q000737:chemistry; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D011060:Poloxalene / Q000737:chemistry / Q000302:isolation & purification*; D011137:Polystyrenes / Q000737:chemistry; D013501:Surface-Active Agents / Q000737:chemistry / Q000302:isolation & purification; D013696:Temperature; D015040:Zirconium / Q000737:chemistry
chemical_list: D011137:Polystyrenes; D013501:Surface-Active Agents; D002244:Carbon; D011060:Poloxalene; D015040:Zirconium; C028541:zirconium oxide