Preparation of multifunctional chitin nanowhiskers/ZnO-Ag NPs and their effect on the properties of carboxymethyl cellulose-based nanocomposite film

Chitin nanowhiskers (ChNW) were isolated and used for the synthesis of hybrid ChNW/ZnO-Ag NPs. The hybrid nanoparticles were used for the preparation of multifunctional carboxymethyl cellulose (CMC) films. A ChNW was needle shape with the width of 8-40 nm, the length of 150-260 nm, and crystallinity index of 93.6%. The ZnO-Ag NPs were spherical with the diameter of 10.5-16.2 nm. STEM, EDX, XRD, and UV-vis analyses confirmed the formation of ZnO-Ag NPs on the surface of ChNW. The thermal stability of ChNW was increased by incorporation of ZnO-Ag NPs. A CMC-based nanocomposite film incorporated with 5 wt% of ChNW/ZnO-Ag NPs was homogeneous and showed the high UV-barrier property. The tensile strength (TS) and elastic modulus (E) of the composite film increased by 18-32% and 55-100%, respectively, while the elongation at break (EB) decreased by 23-33%. CMC composite films showed strong antibacterial activity against E. coli and L. monocytogenes.