Preparation of nanocellulose from steam exploded poplar wood by enzymolysis assisted sonication

Abstract

By exploiting cellulose nanofibril’s high aspect ratio and nano-order-unit interconnected web-like structure of poplar wood, a new approach was designed. Steam explosion was used for the pretreatment of the poplar, followed by enzymatic hydrolysis assisted sonication for the preparation of nanocellulose. The effects the cellulase dosage, enzymatic hydrolysis time and temperature on the yield of nanocellulose were studied. Under optimal conditions nanocellulose yield was approximately 13.2%. The chemical composition, crystallinity, and morphology of the composites were characterised using FT-IR, x-ray diffraction and TEM. The results demonstrated that the structure was not destroyed during the preparation process, that the crystal form remained cellulose I, and the crystallinity was 61.98%, 9.15% higher than that of poplar cellulose. The width was between 20 and 50 nm, with high aspect ratio and a web-like entangled structure. Therefore, nanocellulose prepared using this method is an ideal toughening material that could be applied in composite materials.