Preparation of cationic lignocellulose nanofibers from reed straw via mechanochemical method and its application

Crop wastes are renewable and abundant lignocellulosic resource, while their effective utilization is limited due to the recalcitrance of plant cell wall. In this study, by using a facile mechanochemical method, reed straw fiber was simultaneously cationized and defibrillated to obtain cationic lignocellulose nanofibers (LCNFs) without organic solvent. The obtained cationic LCNFs were 2–4 nm wide and several micrometers long with excellent re-dispersibility in water arising from the high zeta potential of + 40 mV. As a paper-reinforcement agent, cationic LCNFs could give coated paper good oil resistance with the maximum Kit rating of 12/12. Meanwhile, the mechanical properties of the coated paper were also remarkably enhanced with the tensile strength and Young’s modulus increased by 144% and 124%, respectively. They also gave the paper antibacterial properties because of the presence of quaternary ammonium groups. Overall, this study provides an efficient utilization option for crop wastes as well as a value-added lignocellulosic product. Graphical abstract