Xylan is a predominant hemicellulose component that is found in plants and in some algae. This polysaccharide is made from units of xylose (a pentose sugar). One promising source of xylan is oat spelt. This feedstock was used for the synthesis of two xylan ethers. To achieve water soluble products, we prepared dihydroxypropyl xylan as a non-ionic ether on the one hand, and carboxymethyl xylan as an ionic derivative on the other hand. Different preparation methods like heterogeneous, pseudo-homogeneous, and homogeneous syntheses were compared. In the case of dihydroxypropyl xylan, the synthesis method did not significantly affect the degree of substitution (DS). In contrast, in the case of carboxymethyl xylan, clear differences of the DS values were found in dependence on the synthesis method. Xylan ethers with DS values of >1 could be obtained, which mostly show good water solubility. The synthesized ionic, as well as non-ionic, xylan ethers were soluble in water, even though the aqueous solutions showed slight turbidity. Nevertheless, stable, transparent, and stainable films could be prepared from aqueous solutions from carboxymethyl xylans.

Cellulose was dissolved in a solvent mixture containing N‐methylmorpholine‐N‐oxide (NMMNO), diethylenetriamine (DETA) and water. The weight‐average molar masses Mw, radii of gyration RG, and second virial coefficients A2 of 9 different cellulose samples were determined by means of static light scattering (SLS) at room temperature. The influence of two different dissolution procedures was studied on four samples. The Mw results were compared with results obtained by gel permeation chromatography (GPC) with multi angle laser light scattering (MALLS) detection. The original samples and samples recovered from the solvent mixture by precipitation were tricarbanilated and dissolved in tetrahydrofuran for the GPC analysis. The SLS results led to the conclusion that cellulose was molecularly dispersed in the solvent mixture NMMNO/H2O/DETA. The Mw dependence of the radii of gyration showed a common power law behavior with an exponent which is identical to the theoretical value for flexible, linear chains in good solvents. The observed differences between SLS and GPC results, especially for the high‐molecular samples, can be explained by a molecular degradation of cellulose during the dissolution in NMMNO/H2O/DETA. The different dissolution procedures and the use of potassium pyrophosphate as a stabilizer showed no significant effect on the determined results.