Structure and thermal properties of cellulose nanofibrils extracted from alkali–ultrasound treated windmill palm fibers

Windmill palm, a tree species that is native to China, has gained attention with regard to the production of substantial amounts of biomass fibers via yearly pruning. This study investigates the structure and thermal properties of cellulose nanofibrils (CNFs) obtained from windmill palm biomass, with the goal of promoting the usage of these CNFs. Alkali–ultrasound treatments are employed herein to prepare samples of the CNFs. The micromorphology of the prepared samples is observed using scanning electron microscopy, atomic force microscopy, and transmission electron microscopy. Furthermore, X-ray diffraction analysis is used to examine the aggregated structure of the samples, and thermogravimetric analysis is used to investigate their thermal properties. Results indicate that during alkali hydrolysis when obtaining CNFs, the fiber cell wall exhibits distinct spiral cracking. The diameter of the obtained nanocellulose is