Preparation of ultrafine hydrophobic lignin-contained cellulose nanofiber via mechanochemical method and its films

Abstract

The high-value utilization of lignin-containing biomass waste generated during processing has gained widespread attention with the growing demand for renewable resources represented by bamboo. Herein, the 3,4-dichlorophenyl isocyanate (DCPI) was employed for mechanochemical derivatization/dispersion of bamboo powder after low concentration alkali pretreatment, in which an ultrafine hydrophobic carbamylated lignin-contained cellulose nanofiber (CLCN)¹ with a diameter of 2±1 nm was obtained. By adjusting the usage of DCPI and milling time, the nanometric defibrillation of lignin-contained cellulose can be promoted effectively, which further endow high stability of CLCN-suspension. Whereas, the CLCN-films possessed controllable optical properties, wettability and UV resistance, ensuring the haze above 80 % with a total optical transmissivity up to 86 % at 550 nm. Furthermore, it maintained a UV blocking efficiency exceeding 90 %, accompanied by a water contact angle of 86.4° and tensile strength of 83.26 MPa. This is conducive to expanding the application of lignin-containing biomass waste.