Title
Solubility of lignocellulose in NNdimethylacetamide/ lithium chloride. WAXS 13 CP/MAS NMR FTIR and SEM studies of samples regenerated from the solutions
Authors
N. E. KOTELNIKOVA Yu. V. BYKHOVTSOVA A. M. MIKHAILIDI M. V. MOKEEV N. N. SAPRYKINA V. K. LAVRENT'EV and E. N. VLASOVA

Received August 17, 2013
Published Volume 48 Issue 7-8 July-August
Keywords lignocellulose, waste flax, wood pulp, DMAc/LiCl, WAXS, 13С CP/MAS NMR spectroscopy, IR-Fourier spectroscopy, SEM

Abstract
The solubility of powder lignocelluloses from flax wastes and wood pulps in the N,N-dimethylacetamide/lithium chloride (DMAc/LiCl) system was studied. The chemical “purity” and the degree of polymerization of the lignocelluloses mainly affected their dissolving capacity. Regenerated cellulose samples prepared by precipitating cellulose solutions with water were studied with wide angle X-ray diffraction (WAXS), high-resolution 13С CP/MAS nuclear magnetic resonance in a solid state (13С CP/MAS NMR), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). WAXS study revealed that the cellulose I supramolecular structure of the powder samples regenerated from solutions underwent a mixture of polymorph modifications. As revealed with FTIR, C1-C4 conformational transitions of the anhydroglucose units did not occur. However, changes in the H-bond system in the lignocellulose chains for the regenerated samples were registered. The powder samples degraded at the fibrillar level in the solutions.