Nanoarchitectonics of Silver/Poly (Methyl Methacrylate) Films: Structure, Optical Characteristics, Antibacterial Activity, and Wettability

Functionalizing organic–inorganic materials for use in packaging technologies, such as polymers wrapped in thin metal, has proven to be one of the more successful strategies. In this study, the direct current (DC) sputtering technique under a vacuum of 3 × 10−5 Torr was used to deposit silver (Ag) films of thicknesses of 100 and 300 nm on poly (methyl methacrylate) (PMMA) polymer. The structural, optical, antibacterial activity, and wettability properties of Ag/PMMA were carried out using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE-SEM), atomic force microscopy (AFM), UV spectrophotometer, and contact angle. The cubic crystal structure phase of Ag was confirmed by the XRD. The Ag coating layer has consistent nanomorphology, according to AFM, and the PMMA substrate surface was well coated with Ag nanoparticles. As the Ag film thickness rose, the optical band gap values of Ag/PMMA slightly increased. In addition, it has been found that these optical characteristics such as extension coefficient, optical density, and optical surface resistance essentially depend on the thickness of the Ag layers. Both samples of pure PMMA and Ag/PMMA polymers show no activity against E. coli. In the meantime, S. aureus activity is detected in the Ag/PMMA samples, and the antibacterial activity is slightly influenced by the Ag thickness. The contact angle rose as the Ag film thickness grew over the PMMA, resulting in a decrease in the wettability of the liquid which is required for food packaging technology.