Evaluation of comprehensive on-line liquid chromatography thermally assisted hydrolysis and methylation-gas chromatography-mass spectrometry for characterization of sulfonated lignins.
Sulfonated lignins, used as dispersants in agrochemical formulations, have been characterized by hyphenation of ion-pair RPLC and thermally assisted hydrolysis and methylation-GC-MC (THM-GC-MS). The chemical structure of a series of selected lignins was evaluated, both in terms of overall composition and in terms of composition as a function of molecular size. Some sulfonated lignins give rise to unstable formulations. In the compositional analysis, these samples were found to yield additional fragments. A newly developed comprehensive method made it possible to monitor the occurrence of these fragments as a function of molecular size. In addition to differences in the molecular size between "good" and "bad" batches, clear differences in chemical composition were established.
Analytical-Chemistry/Forensic-Science Group (HIMS), University of Amsterdam, Faculty of Science, Amsterdam, The Netherlands. s.s.brudin@uva.nl
Stella
S
Brudin
Erwin
E
Kaal
Hans-Gerd
HG
Janssen
Peter
P
Schoenmakers
D002853:Chromatography, Liquid; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry*; D008745:Methylation; D013451:Sulfonic Acids / Q000737:chemistry*
D013451:Sulfonic Acids; D008031:Lignin