Two-dimensional chromatography of complex polymers, 8. Separation of fatty alcohol ethoxylates simultaneously by end group and chain length.
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.
German Institute for Polymers, Darmstadt, Germany.
Jacques-Antoine
JA
Raust
Adele
A
Bruell
Pritish
P
Sinha
Wolf
W
Hiller
Harald
H
Pasch
D002853:Chromatography, Liquid; D005233:Fatty Alcohols / Q000737:chemistry* / Q000302:isolation & purification*; D011108:Polymers / Q000737:chemistry* / Q000302:isolation & purification*
D005233:Fatty Alcohols; D011108:Polymers