Light scattering by cellulose. V. Anisotropy scattering by wood fibers

Abstract

Solid state light scattering patterns from single wood fibers were recorded using a laser as the light source. The scattering was recorded in the Hv mode; i.e., with the incident light beam vertically polarized, the scattered light was passed through a horizontal analyzer, thus permitting the recording of only the scattering arising from anisotropy fluctuations. The scattering pattern was confined to a narrow line consisting of regularly spaced maxima and minima. The overall scattering envelope could be accounted for by a hollow cylindrical model with helically wound dipoles, while the periodicity in the intensity is a function of fiber diameter and cell wall thickness. Comparison of relative intensities led to the conclusions that cellulose of the wood fiber behaves optically as a biaxial crystal in that the cellulose crystallites are biaxially oriented in an axial‐tangentoplanar fashion in the cell wall.