High-intensity ultrasound irradiated modification of sugarcane bagasse cellulose in an ionic liquid

This current work is concerned with the glutarylation of sugarcane bagasse cellulose in ionic liquid 1-butyl-3-methylimidazolium chloride by ultrasound irradiation without catalyst. The degree of substitution ranging from 0.22 to 1.20 was obtained in one-step homogeneous modification, which increased with ultrasound irradiation time, temperature, and the molar ratio of glutaric anhydride/anhydroglucose unit in cellulose. The structural characterization of the glutarylated cellulose was carried out by using FT-IR and CP/MAS 13C NMR and the results showed that the glutarylation reaction occurred. The thermal stability of the glutarylated cellulose decreased upon chemical modification.

• Ionic liquid (IL) 1-butyl-3-methylimidazolium chloride as a dissolution solvent and reaction medium for glutaration of cellulose. • Esterification of cellulose and glutaric anhydrate in IL by ultrasound irradiation without catalyst. • The degree of substitution ranging from 0.22 to 1.20 was obtained in one-step homogeneous modification.