Changes in the cellulose fiber wall supramolecular structure during the initial stages of chemical treatments of wood evaluated by NMR and X-ray scattering

Abstract The effect of initial stages pulping spruce, resembling prehydrolysis and alkaline cooking was studied using CP/MAS 13 C-NMR, X-ray scattering, FSP carbohydrate composition in order to study the impact pre-treatments on fiber wall nanostructure. Removal components, hemicellulose lignin, increased porosity induced cellulose fibril aggregation. temperature pH treatment aggregate size appears be secondary. It is removal that has a profound supramolecular structure wall. As amount dissolved from wood increases, determined by NMR increases as well, ranging 16 28 nm. Specifically, good correlation between glucomannan seen. lower glucomannan, larger size. Glucomannan thus seems prevent aggregation it acts very efficient spacer fibrils. Elemental NMR, quite similar for all samples, 3.6 4.1 By combining measurement methods, more well-resolved picture structural changes occurring during obtained.