In this study, antimicrobial packaging films were prepared by coating silver (Ag) nanoparticles onto the surface of low density polyethylene (LDPE) films modified by corona air plasma. The possibility of these films for use in the packaging of milk was studied. The influence of input power of the corona discharge treatment on the surface modification and performance of the fabricated Ag/LDPE nanocomposite films was also investigated. The prepared antimicrobial packaging films showed promising antimicrobial efficiency against micro-organisms that are present in milk and were able to increase the microbial shelf life of the milk. Packages fabricated at corona input powers of 210, 500 and 800 W reached the maximum limit after 5, 8 and 14 days (respectively).

Titanium dioxide (TiO2) nanoparticles due to their exclusive physical, chemical and electrical properties are widely used as a heterogeneous catalyst and catalytic support in the chemical reactions, a semiconductor for photocatalysis reactions and additives in the membrane processes. The TiO2 nanoparticles are also utilized in solar cells, gas sensors, pigments and etc. Efficiency of these nanoparticles in various applications is dramatically dependent on their size. Various techniques such as combustion flame synthesis and conventional hydrothermal methods have been used to prepare TiO2 nanoparticles, but few synthesis techniques can reproducibly produce particles below 10 nm. In this study, the TiO2 nanoparticles in rutile phase were synthesized by microwave assisted hydrothermal method by controlling the crystallization time and temperature. Titanium tetrachloride (TiCl4) was used as a titanium precursor. The synthesized nanoparticles were characterized by X-ray powder diffraction (XRD) and Scanning Electron Microscope (SEM) analysis. The XRD pattern showed that the rutile phase of the TiO2 nanoparticles was successfully synthesized by the proposed method with the average crystal size of 4nm. Finally, the prepared Titanium dioxide (TiO2) nanoparticles were as a hydrophobic additive in the polymeric ultrafiltration membranes in order to reduce the membrane fouling.