Biodegradable kefiran-chitosan-nanocellulose blend film: Production and physical, barrier, mechanical, thermal, and structural properties

In this study, biodegradable kefiran-chitosan-nanocellulose blend films were developed and their physical, mechanical, barrier, thermal and structural properties determined. Results showed that adding nanocellulose had not any significant effect on the thickness, moisture content and water solubility. Also, water vapor permeability, tensile strength and lightness increased and the elongation at break, glass transition and melting temperatures, chromaticity parameters of red–green and yellow–blue, total color difference, and whiteness index decreased by increasing the nanocellulose content. Scanning electron microscopy demonstrated that at high concentrations of nanocellulose, the nanoparticle dispersion was not uniform and many agglomerations observed in the surface and cross-section of the nanocomposites. In the end, XRD analysis showed that the dispersed phase of nanocellulose could not indicate its own crystalline peaks in the kefiran-chitosan matrix.