Green nanocomposite made from carboxymethyl cellulose reinforced with four types of cellulose nanomaterials of wheat straw

Abstract

AbstractIn this study, four types of cellulose nanomaterials obtained from wheat straw including cellulose nanocrystals (CNCs), TEMPO oxidized cellulose nanofibers (TCNFs), mechanical‐driven cellulose nanofibers (MCNFs) and lignocellulose nanofibers (LCNFs) were first produced and then separately added to carboxymethyl cellulose (CMC) with different mixing ratio of 1, 3, and 6 wt% to make nanocomposite. Pure CMC film and cellulose microfibers (CFs) reinforced composite were also fabricated. BET test showed that TCNFs and CFs had the highest (124 m2/g) and lowest (3.6 m2/g) specific surface area, respectively. FE‐SEM confirmed that TCNFs and CFs presented the thinnest (8 ± 4 nm) and the thickest (24 ± 7 μm) fibers. The nanocomposite containing TCNFs had a transparency of 56%, while CF‐CMC composite showed the lowest one (18%). After the addition of cellulose nanomaterials the XRD peaks of nanocomposites became narrower and shifted partly to the right side compared to that of pure CMC. The highest and lowest water vapor permeability values obtained for rod‐like CNC reinforced nanocomposite and pure CMC film, respectively. The nanocomposite containing 6 wt% TCNFs showed the highest tensile strength and Young's modulus. Cellulose nanomaterials positively affected on the strain at break of the nanocomposites.