Vegetable oil reactions within wood studied by direct 13C excitation with 1H decoupling and magic-angle sample spinning (MAS) NMR

Autor: István Furó, Mats Johansson, Guilhem Pages, M Alireza Salehi, Sergey V. Dvinskikh
Přispěvatelé: Qualité des Produits Animaux (QuaPA), Institut National de la Recherche Agronomique (INRA), Royal Institute of Technology in Stockholm (KTH), Wallenberg Laboratory, Göteborgs Universitet (GU), Knut and Alice Wallenberg Foundation via the Wallenberg Wood Science Center, Swedish Research Council VR, Swedish Research Council Formas, 243-2006-273
Rok vydání: 2012
Předmět:
Zdroj: Progress in Organic Coatings
Progress in Organic Coatings, Elsevier, 2012, 75 (3), pp.259-263. ⟨10.1016/j.porgcoat.2012.05.007⟩
ISSN: 0300-9440
DOI: 10.1016/j.porgcoat.2012.05.007
Popis: International audience; Despite having been used for ages to protect wood against the influence of outdoor elements, the chemistry of vegetable oils within wood is poorly known. We propose a method based on solid-state magic-angle sample spinning NMR to in situ characterize oil oxidation as well as its immobilization. To eliminate signal coming from wood molecules but to keep signal from the oil, direct 13C excitation is performed with low-power 1H decoupling during signal acquisition. To suppress the effect of anisotropic spin-interactions and magnetic field inhomogeneity, the sample is spun at the magic-angle. Mono- and polyunsaturated fatty acid derivatives show a difference in their oxidation process: the monounsaturated methyl oleate reacts with wood components and becomes immobilized while the polyunsaturated methyl linoleate becomes oxidized and form oligomers but does not seem to bind to wood. Linola® oil behaves as would be expected on the basis of its composition by monounsaturated and polyunsaturated chains. This method can be generalized to all coating treatments to characterize chemical pathways and reactions. A better understanding of coating effects on wood is a crucial step to design more efficient protective mixtures.
Databáze: OpenAIRE