Moisture in untreated, acetylated, and furfurylated Norway Spruce monitored during drying below fiber saturation using time domain NMR
Author: Thygesen, Lisbeth G.; Elder, Thomas;
Source: Wood and Fiber Science 41(2): 194-200.
Publication Series: Scientific Journal (JRNL)
Using time domain–nuclear magnetic resonance spectroscopy, the moisture content (MC) in Norway spruce [Picea abies (L.) Karst.] sapwood, subjected to three different treatments (untreated, acetylated, and furfurylated), was studied during drying at 40oC at MCs below fiber saturation. Spin–spin relaxation time distributions were derived from Carr-Purcell-Meiboom-Gill relaxation curves using mulitexponential fitting (CONTIN). After conditioning for 6 wk at 100% RH, the modified wood samples had a MC of about 15%, whereas the MC of the untreated samples was about 30%. Two water populations with different relaxation times were found in all three sample types at this point: 1.1 ms and 0.15 ms (untreated), 0.5 ms and 0.15 ms (furfurylated), and 1.2 – 3.5 ms and 0.1 ms (acetylated). As the MC decreased, the relaxation time of the most slowly relaxing population decreased, whereas it remained more or less constant for the other population. For both the untreated and the furfurylated samples, the two populations merged at 5 – 10% MC, and relaxation times were identical for the two treatments at low MC. The two populations did not merge for the acetylated samples. These results indicate that while acetylation changed the interaction between water and the wood cell wall, furfurylation seemed to mostly affect the amount of water present within the cell wall at the beginning of the drying experiment.
Keywords: Time domain NMR, spin spin relaxation, wood, moisture, water, acetylation, furfurylation
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
XML: View XML
Thygesen, Lisbeth G.; Elder, Thomas 2009. Moisture in untreated, acetylated, and furfurylated Norway Spruce monitored during drying below fiber saturation using time domain NMR. Wood and Fiber Science 41(2): 194-200.
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility