Preparation and characterization of active emulsified films based on chitosan-carboxymethyl cellulose containing zinc oxide nano particles.

Active nanocomposites based on carboxymethyl cellulose-chitosan-oleic acid (CMC-CH-OL) incorporated with different concentrations (0.5-2wt.%) of zinc oxide nanoparticles (ZnO NPs) were produced by casting method. The effects of ZnO NPs on the morphological, mechanical, thermal, physical and antifungal properties of the films were studied. New interaction between ZnO NPs and polymer matrix were confirmed by Fourier Transform infrared. After addition of ZnO NPs, tensile strength, lightness (L*) and thermal stability decreased however, elongation at break, contact angle, a* (greenness) and b* (yellowness) of the nanocomposite films increased in comparison to the films without nano-filler. UV transmittance at 280nm decreased from 17.3% to 0.2, 0.1 and 0.1 for the nanocomposite films containing 0.5, 1 and 2wt.% ZnO NPs, respectively, suggesting higher UV blocking properties. Disc diffusion test showed considerable antifungal properties of the active nanocomposite films against Aspergillus niger, especially in CMC-CH-OL-ZnO 2wt.% by more than 40% fungal growth inhibition.