Light scattering by cellulose. I. Native cellulose films

Abstract

Crystalline cellulose films are analyzed by solid‐state light scattering, using a photographic technique. The light‐scattering envelopes may be theoretically predicted by assuming a model consisting of randomly oriented anisotropic rods. The experimentally observed anisotropy patterns are discussed in terms of this model and are related to various ways in which the fibrils may aggregate. These are often visible in electron micrographs of cellulose materials. The method is applicable to paper samples which are sufficiently thin and dense.

Cellulose Nanofibers from Softwood, Hardwood, and Tunicate: Preparation–Structure–Film Performance Interrelation

“…eTC forms the most opaque film with a transmittance of 2.2%, significantly lower than 14.5 and 14.0% for eSW and eHW, respectively. This difference might originate from the fact that larger fibrils are present in eTC than in the wood CNF, which would cause more light scattering and thus reduce the film transmittance . Additionally, the high porosity and presence of air bubbles within the films are more reasons for the low transmittance.…”

“…This difference might originate from the fact that larger fibrils are present in eTC than in the wood CNF, which would cause more light scattering and thus reduce the film transmittance. 60 Additionally, the high porosity and presence of air bubbles within the films are more reasons for the low transmittance. On the contrary, after TEMPO-mediated oxidation, tTC (22.0%) and tSW (90.2%) films showed transmittance much higher than those of eTC (2.2%) and eSW (14.5%) (Table 4) due to the surface charge introduction, which improves the cellulose disintegration, resulting in more elementary fibrils and making the films more uniform and of higher density.…”

Transparent Composites Made from Tunicate Cellulose Membranes and Environmentally Friendly Polyester

“…[25] In addition, the surfacer ootmean-square (RMS) roughness of the composites cured by oven (110 8C, 36 h) and hot metal plate (200 8C, 40 min) were 22.78 AE 2.14 nm and 21.88 AE 4.38 nm, respectively.B yc omparison to an RMS roughness of 50.47 AE 6.56 nm for cellulose membrane, the introductiono fp olyester significantly improvedt he smoothness of the composites, thought he roughness in nanoscale could still lead to ac ertain amount of light scattering. The cellulose aggregates could be ac ontributor to light scattering, especially the ribbon-like aggregates and cellulose fibril bundles (see below,F igure 9a).…”

The scattering of light by correlated assemblies of anisotropic rods in two dimensions

“…The result of this derivation may be written as fol- -k 16 As we have done previously, using eqs. (13) and (15), we may write This means that €or a wavelength of light of 0.546 pm, for angles e 5 lo", x e can calculatc the scattering patterns for values of L _< 1 pm. As we will see in the next section, this is a scrious limitation.…”