Characterization of wood components of Portuguese medieval dugout canoes with high-resolution solid-state NMR

• Published in: Carbohydrate polymers 2004-09, Vol.57 (4), p.419-424
• Main Authors: Bardet, Michel, Foray, Marie F., Maron, Sébastien, Goncalves, Pedro, Trân, Quôc K.
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Applied sciences; Archaeological woods; canoeing; carbon; Celluloses; Chemical Sciences; Condensed Matter; degradation; Exact sciences and technology; hemicellulose; Inorganic chemistry; lignin; Lignins; lignocellulose; Materials Science; Miscellaneous; nuclear magnetic resonance spectroscopy; old and fossil wood; Physics; Polymer industry, paints, wood; Portuguese medieval dugout canoes; Solid-state NMR; stable isotopes; sugars; water content; watercraft; Waterlogged woods; Wood; wood anatomy; Wood. Paper. Non wovens
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2004.05.012

High-resolution nuclear magnetic resonance of carbon 13 was employed to characterize archaeological wood samples from Portuguese medieval dugout canoes. Structural and chemical modifications were assessed by comparing the structural features of archaeological wood samples with modern wood. The main results concern the strong decrease of sugar moiety with a complete disappearance of hemicelluloses. During ageing in water environment, the β-O-4 inter-unit linkages of lignins have not been degraded. The features of the 13C NMR spectra clearly reveal that the products of degradation of the carbohydrates occurring during depletion of sugars were not recombined inside the lignocellulosic matrix. Finally, this article gives a clear illustration that although the water contents of archaeological wood can certainly be used as a good criterion concerning their state of degradation, solid-state 13C NMR lead to unambiguously data as far the structural properties of archaeological waterlogged woods are concerned.