Characterization of Low-Molecular Weight Iodine-Terminated Polyethylenes by Gas Chromatography/Mass Spectrometry and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry with the Use of Derivatization
Autor: | Vladimir G. Zaikin, Aleksei V. Ivanyuk, Aleksei A. Vinogradov, Nikolai Yu. Polovkov, D. I. Zhilyaev, Roman S. Borisov |
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Rok vydání: | 2013 |
Předmět: |
Chemistry
Analytical chemistry Thermospray General Medicine Models Theoretical Mass spectrometry Capillary electrophoresis–mass spectrometry Gas Chromatography-Mass Spectrometry Atomic and Molecular Physics and Optics Sample preparation in mass spectrometry Molecular Weight Matrix-assisted laser desorption/ionization Spectrometry Mass Matrix-Assisted Laser Desorption-Ionization Mass spectrum Salts Polyethylenes Direct electron ionization liquid chromatography–mass spectrometry interface Inductively coupled plasma mass spectrometry Spectroscopy Iodine |
Zdroj: | European Journal of Mass Spectrometry. 19:163-173 |
ISSN: | 1751-6838 1469-0667 |
Popis: | Gas chromatography/mass spectrometry (GC/MS) and matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometry, in conjunction with various derivatization approaches, have been applied to structure determination of individual oligomers and molecular-mass distributions ( MMD) in low-molecular mass polyethylene having an iodine terminus. Direct GC/MS analysis has shown that the samples under investigation composed of polyethyelene-iodides (major components) and n-alkanes. Exchange reaction with methanol in the presence of NaOH gave rise to methoxy-derivatives and n-alkenes. Electron ionization mass spectra have shown that the former contained terminal methoxy groups indicating the terminal position of the iodine atom in the initial oligomers. MMD parameters have been determined with the aid of MALDI mass spectrometry followed by preliminary derivatization-formation of covalently bonded charge through the reaction of iodides with triphenylphosphine, trialkylamines, pyridine or quinoline. The mass spectra revealed well-resolved peaks for cationic parts of derivatized oligomers allowing the determination of MMD. The latter values have been compared with those calculated from GC/MS data. |
Databáze: | OpenAIRE |
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