Fabrication of All‐Cellulose Nanocomposites from Corn Stalk

BACKGROUND: In order to help farmers and industries develop value-added composite and nano materials from agricultural residuals. Cellulose nanofibers (CNFs) were made by using a TEMPO oxidation method and celluloses were prepared by acid-base method and extracting method, which were all from corn stalk, an agricultural residual. The prepared celluloses were dissolved separately in DMAc/LiCl solvent and added CNFs of 0.0, 0.5, 1.5 and 3.0% to form all-cellulose nanocomposite, and then casted into films. Morphology, structure and properties of the nanocomposite films were characterized by atomic force microscopy (AFM), field emission scanning electron microscope (FE-SEM), thermogravimetry analysis (TGA), X-ray diffraction (XRD), and mechanical testing. RESULTS: The all-cellulose nanocomposite films with different cellulose cellulose matrix exhibited a good optical transparency and layer structure. The all-cellulose nanocomposites films with the cellulose prepared by the extracting method (Composite E) exhibited a higher crystallinity, better thermal stability and higher mechanical strength than those of the all-cellulose nanocomposites films with the cellulose prepared by the acid-base method (Composite A). CONCLUSION: Crystal structure of the all-cellulose nanocomposite films all presented a co-existence of Cellulose I and Cellulose II. However, on the contrary to Composite A, the diffraction intensity of Cellulose I in Composite E was higher than that of Cellulose II. This was another reason that the mechanical properties of Composite E were superior to Composite A. In addition, the mechanical properties of the all-cellulose nanocomposites films were significantly different when the addition of CNF reached 3.0% in weight, as indicated by a multiple-range comparison. This article is protected by copyright. All rights reserved.