Green all-cellulose nanocomposites made with cellulose nanofibers reinforced in dissolved cellulose matrix without heat treatment

Abstract

Green all-cellulose nanocomposites were fabricated by adding reinforcing cellulose nanofiber (CNF) to a matrix of dissolved cellulose. CNFs were isolated from one dried native hardwood bleached Kraft pulp and office waste recycled deinked copy/printing paper (DIP) by using the TEMPO oxidation method. The cellulose was dissolved by using DIP and DMAc/LiCl solvent without heat treatment and solvent exchange to form a matrix of the all-cellulose nanocomposites. The DIP was not only selected for CNF isolation, but also for the cellulose matrix. The isolated CNFs and the all-cellulose nanocomposites were characterized by atomic force microscopy, thermogravimetry–differential thermal analysis, X-ray diffraction and mechanical tensile testing. The green all-cellulose nanocomposites made without heat treatment offered better thermal stability, crystallinity and mechanical properties than the heat treated ones. CNFs isolated from two resources show similar reinforcement capacity in all-cellulose nanocomposites. All-cellulose nanocomposite fabrication by dissolving cellulose without heat treatment and solvent exchange is a simple way that saves energy and chemicals.