Tuning of size and properties of cellulose nanofibers isolated from sugarcane bagasse by endoglucanase-assisted mechanical grinding

This study explores the possibility of producing tunable cellulose nanofibers (CNFs) with a wide range of size and properties from sugarcane bagasse in an energy-efficient manner, which is very meaningful for specific application of CNFs. The bleached bagasse kraft pulp was subjected to endoglucanase pretreatment with a wide range of enzyme dosage followed by mechanical grinding to obtain size-tunable CNFs. The size distribution and structural characteristics of CNFs, energy consumed during the CNF production process, and properties of CNF films were systematically investigated as a function of the enzyme dosage applied in the pretreatment. The results showed that endoglucanase-assisted mechanical grinding was able to produce CNFs with controllable length (298–4500 nm) and diameter (9–26 nm), meanwhile improving CNF yield and energy-efficiency. The controllable range of CNF length was extremely wide based on our best knowledge. The optical performance and mechanical properties of the prepared CNF films could be effectively tuned by regulating the structural characteristics of the CNFs. Moreover, all the as-prepared CNFs retained high thermal stability. The tailor-made CNFs from sugarcane bagasse are expected to provide compatibility with various CNF-related applications.