Fig. 3
From: Wood morphology and properties from molecular perspectives
Polar graph (0o to 90o) of the absolute absorbance of xylan-, glucomannan- and cellulose-specific peaks in spruce wood fibres (Salmén et al. 2012). The cellulose 1,160 cm−1 peak is oriented along the molecule while the 1,460 cm−1 xylan peak and the 810 cm−1 glucomannan peaks are oriented transversely to the polymer chains. In the latter case, a higher absorption in the 90o direction than in the 0o direction indicates a polymer orientation at 0o. The dotted line indicates the case of a completely isotropic orientation