The application of different ionic liquids (IL), namely 1-N-butyl-3-methylimidazolium chloride ([C(4)mim](+)Cl(-)), 3-methyl-N-butyl-pyridinium chloride and benzyldimethyl(tetradecyl)ammonium chloride were investigated as solvents for cellulose. The ILs used have the ability to dissolve cellulose with a degree of polymerization in the range from 290 to 1 200 to a very high concentration. Using [C(4)mim](+)Cl(-), no degradation of the polymer appears. By (13)C NMR measurement it was confirmed that this IL is a so-called non-derivatizing solvent. [C(4)mim](+)Cl(-) can be applied as a reaction medium for the synthesis of carboxymethyl cellulose and cellulose acetate. Without using any catalyst, cellulose derivatives with high degree of substitution could be prepared.(13)C NMR spectrum of cellulose dissolved in the IL [C(4)mim](+)Cl(-) (top). The (13)C NMR spectrum of cellulose dissolved in DMSO/tetrabutylammonium fluoride trihydrate is shown for comparison (bottom).

Xylan from birch wood was characterized regarding both the supramolecular structure (X-ray, CP/MAS 13 C-NMR) and the sugar composition. The reaction of the birch wood xylan with 2,3-epoxypropyltrimethylammonium chloride in 1,2dimethoxyethane as slurry medium yields water-soluble, cationic 2-hydroxypropyltrimethylammonium xylan derivatives with high degree of substitution (DS). The DS values up to 1.6 can be controlled by adjusting the molar ratio in a one step synthesis. The structure of the cationic xylan derivatives was confirmed by means of DEPT(135) NMR spectroscopy. Film forming properties of cationic xylan derivatives were investigated with SEM measurements.

The interactions of ionic liquids (IL) with solvents usually used in liquid‐state nuclear magnetic resonance (NMR) spectroscopy are studied. The 1H‐ and 13C‐NMR chemical shift values of 1‐n‐butyl‐3‐methyl (BM)‐ and 1‐ethyl‐3‐methyl (EM)‐substituted imidazolium (IM) ‐chlorides (Cl) and ‐acetates (Ac) are determined before and after diluting with deuterated solvents (DMSO‐d6, D2O, CD3OD, and CDCl3). The dilution offers structural modifications of the IL due to the solvents capacity to ionization. For further investigation of highly viscous cellulose dopes made of imidazolium‐based IL, solid‐state NMR spectroscopy enables the reproducibility of liquid‐state NMR data of pure IL. The correlation of liquid‐ and solid‐state NMR is shown on EMIM‐Ac and cellulose/EMIM‐Ac dope (10 wt %).

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