title: Two-dimensional chromatography of complex polymers, 8. Separation of fatty alcohol ethoxylates simultaneously by end group and chain length.
abstract: A comprehensive two-dimensional liquid chromatography system was developed to precisely describe the molecular heterogeneity of fatty alcohol ethoxylates. The end-group functionality was analyzed by gradient HPLC while ethylene oxide oligomer distributions were characterized by liquid adsorption chromatography. A baseline separation of all functionality fractions irrespective of the ethylene oxide oligomer chain length was achieved on nonpolar X-Terra(®) C(18) with a methanol-water gradient, whereas an isocratic flow of isopropanol-water on a polar Chromolith(®) Si column gave a separation according to the oligomer chain length without interference of the end-group distribution. The combination of these two methods to conduct online two-dimensional liquid chromatography experiments resulted in a comprehensive two-dimensional picture on the molecular heterogeneity of the sample.
authors.affiliation: Deutsches Kunststoff-Institut (German Institute for Polymers), Darmstadt, Germany.
authors.forename: Jacques-Antoine
authors.initials: JA
authors.lastname: Raust
authors.forename: Adele
authors.initials: A
authors.lastname: Bruell
authors.forename: Pritish
authors.initials: P
authors.lastname: Sinha
authors.forename: Wolf
authors.initials: W
authors.lastname: Hiller
authors.forename: Harald
authors.initials: H
authors.lastname: Pasch