Production of ZnO doped photocatalytic active packaging

Within the scope of the thesis study, photocatalytic active packaging material containing zinc oxide nanoparticles was produced. For this, first, a purity analysis of zinc oxide nanoparticles was performed. Then, the minimum inhibition concentration and minimum bactericidal/fungicidal concentration of zinc oxide nanoparticles on Escherichia coli and Aspergillus niger were determined under UV-visible light and in the dark. The effects of the differences in zinc oxide concentration, chitosan concentration and bulk volume of the films on the chemical and physical properties of the films were investigated. In this direction, the thickness, color, moisture content, moisture absorption capacity, hydrophobicity properties of the films were examined and cost evaluation was made. The film with the best features was chosen as the optimum film. In addition to the selected film, the photocatalytic degradation activities, XRD patterns, FT-IR spectroscopy, water solubility and antimicrobial activities of films containing zinc oxide at different concentrations were investigated. As a result, films containing 0.2% ZnO and 1.5% chitosan were chosen as the optimum film. In addition to the selected films, films containing 0.1% ZnO and 0.3% ZnO were selected by keeping the chitosan concentration constant. Photocatalytic degradation in selected films was determined to be 87±1% by following the absorbance decrease of methylene blue aqueous solutions. It was determined that increasing zinc oxide concentration decreased the water solubility of the films. When the XRD patterns were examined, sharp peaks belonging to zinc oxide nanoparticles could not be observed since chitosan-based films containing zinc oxide were studied with low concentrations of zinc oxide. FT-IR spectra showed that chitosan-based films containing zinc oxide proved the organic bond structure. The antimicrobial properties of the films were investigated by disk diffusion method. No growth was observed for E.coli only in the region of the films in the light and dark incubation. For A.niger, increasing zinc oxide concentration increased the inhibition zone in dark and light incubation. The largest inhibition diameter for A.niger was observed in films containing 0.3% ZnO in incubation under light.