Stable Suspensions of Lignocellulose Nanofibrils (LCNFs) Dispersed in Organic Solvents

Lignocellulose-based nanomaterials were universally acknowledged as a kind of natural biopolymer and emerging multifunctional nanomaterial. However, the poor dispersion of lignocellulose nanofibrils (LCNFs) would limit their full potential applications. In this work, we reported a simple and industrially viable strategy for the preparation of well-dispersed and thermostable LCNFs from wheat straw (WS) without chemical modification. Diols (ethylene glycol, 1,2-propanediol, and 1,4-butanediol) were employed to swell and crush lignocellulose fibers by screw extrusion. LCNFs could be easily obtained by colloid milling using 0.15% w/w sulfuric acid as a catalyst. The yield of LCNFs was more than 65.2%. The dispersion stability of LCNFs was assessed using an ultraviolet–visible spectrophotometer (UV–vis). Thermal stability of LCNFs was evaluated by thermal gravimetric analysis (TGA). Solvatochromic properties of the swollen solvents were characterized by solvatochromic parameters. The LCNFs were also characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The results confirmed that LCNFs prepared through this process had potential advanced applications.