Poly(vinyl alcohol)/TiO2@Folic Acid Nanocomposite Films: Survey of Optical, Thermal and Antibacterial Properties

The surface modification of the nano-metal oxide has been introduced as an effective methodto improve the dispersion of nanoparticles (NPs) and reduce agglomeration into the polymericmatrix [1]. In this project, the surface of TiO2 NP was modified with folic acid (FA) as a safeand biodegradable molecule. Then, the modified TiO2 NPs were added as a suitable nanofillerinto the matrix of poly(vinyl alcohol) (PVA) with different percentages. The process wasdone by ultrasonic irradiation as a fast, cheap and green method [2]. The TiO2-FA NPs andPVA/TiO2-FA NC films were characterized by different methods. Thermogravimetric analysisand UV-Visible spectroscopy showed the better thermal stability and higher absorption ofNC films in comparison with the pure PVA, respectively. Also, the prepared NC filmsshowed the antibacterial activity under UV irradiation againstEscherichia coli (E. coli) asgram-negative and Staphylococcus aureus (S. aureus) as gram-positive bacteria (Fig. 1). Thisproperty is related to the photo-catalytic property of TiO2 NPs. In fact, in the presence of UVirradiation, the TiO2 NPs can produce the reactive species like hydrogen peroxide, hydroxylradical, and superoxide which can kill the microorganisms [3]. At last, it seems that the preparedPVA/TiO2-FA NC films can be a suitable choice for the packaging system due to antibacterialproperties and high absorption of UV-Vis radiation.