Acetylation of bleached Kraft pulp: Effect of xylan content on properties of acetylated compounds

•Xylan content in acetylation of bleached Kraft pulp (BKP) was studied.•BKP samples were compared with model samples of cotton and hemicelluloses.•A degree of substitution over 95% was obtained in acetylated BKP and model samples.•Xylan content in acetylated BKP samples causes a decrease in melting temperature.•Xylans in acetylated BKP increase the hydrogen bond interaction, as shown in FTIR. Bleached Kraft pulp (BKP) from Eucalyptus globulus and cotton xylan blends (CXB) was acetylated. The effects of xylan content on cellulose acetylation and the properties of the acetylated material were studied. An increase in xylan content caused a slight decrease in the degree of substitution (2.98 to 2.68 for CXB; 2.93 to 2.84 for BKP). Thermal analysis showed that the melting temperature also decreases from 268.0 to 188.8°C for CXB and from 221.4 to 212.8°C for BKP. Moreover, the solubility decreased due to the partial dissolution of acetylated xylans. The presence of xylans during Kraft pulp acetylation does not have a significant negative effect on the physical properties of the acetylated material, but the decrease in melting temperature was beneficial for the application of acetylated polymer as a natural internal plasticizer. This is considered to be an important argument for BKP utilization in the cellulose acetate manufacturing process.