Advanced Biomaterials and Nanotechnology (BIMATEC), Department of Chemical Engineering, University of Girona, 17003 Girona, Spain; Department of Fibre and Polymer Technology, Wallenberg Wood Science Centre, KTH Royal Institute of Technology, SE-100 44 Stockholm, Sweden. Electronic address: [Email]
In recent times, cellulosic materials are witnessing strong interest from both industry and academia for their ability to progress in high-value products with green stamp. Besides the renewability and biodegradability appeal, exceptional properties such as mechanical strength together with toughness are pursued. In the present work, wood fibre networks from eucalyptus Kraft pulp fibres and cellulose nanofibres are combined to produce nanostructured composite networks with outstanding mechanical behaviour. For this purpose, xyloglucan (XG) polymer is adsorbed on cellulose nanofibres (CNF) forming core-shell CNF fibrils in hydrocolloidal suspension which is used to dramatically strengthen wood fibre networks. TEMPO-CNF at two different oxidation levels were coated with XG. The exceptional Young's modulus and tensile strength found for fibre networks with only 10 wt% CNF was attributed to the fibre-fibre bond strength with better homogeneous stress distribution at the micro/nano scale. The production, mechanical characterization and structure analysis of such bionanocomposites is here presented.