Enhanced UV protective behavior of glass materials by boron nitride thin film coatings: Case study as olive oil

The aim of this thesis is to obtain boron nitride nanosheets (BNNSs) thin films with an economical method and to determine some mechanical, physical and optical properties of the glass food packaging. In the thesis, boron nitride nanosheets were produced by liquid exfoliation method at different sonication times (2, 4, 6 hours). Thin film coatings were produced by using a dip-coating method by using boron nitride nanosheet suspension on slide and glass test tubes. The coated glass test tubes were separated into ultraviolet (UV) light by means of extra virgin and riviera olive oil samples (75, 170, 360 and 720 hours). The structural characterization of the obtained BNNSs was evaluated by Transmission Electron Microscopy (TEM), Scanning Electron Microscope (SEM) and Atomic Force Microscopy (AFM) analyses. BNNSs with thicknesses of 1-30 nm and lateral dimensions of 200-500 nm were obtained. The exfoliation efficiencies of BNNSs were determined by UV-Visible Spectrophotometer. The highest yield was calculated as 6.78% after 6 hours sonication time. Physical characterization of thin films was evaluated by SEM and optical microscopy analysis. The presence of functional groups on film was determined by Fourier Transform Infrared Spectrophotometer (FT-IR) and Raman spectroscopy analysis. FT-IR and Raman analyses proved the formation of BNNSs. The optical transmittance of thin films was determined using UV-Visible Spectrophotometer. Optical transmittance of thin films decreased as coating thickness and UV degradation time increased. After UV degradation, FT-IR analysis, specific absorbance coefficient analysis, color analysis, total phenol content, antioxidant removal activities and free fatty acid content were carried out for olive oil samples in coated and non-coated glass bottles. As a result of the analyzes, it was determined that under long-term UV radiation olive oil samples in glass bottles coated with BNNSs were degraded in longer time according to the samples in uncoated glass.