Structural, Optical, Mechanical and Antibacterial Properties of MgO/Poly(Vinyl Acetate)/Poly(Vinyl Chloride) Nanocomposites

Abstract

Polymeric blends and nanocomposites with improved functional properties have attracted attention worldwide for industrial applications. For food packaging applications and carrying purposes, the materials to be used should have UV blocking ability, antibacterial activity, and good mechanical properties. In this study, polyvinyl acetate (PVAc)/polyvinyl chloride (PVC) blends with optimized properties and MgO/PVAc/PVC polymer nanocomposites (PNCs) were prepared by solution casting and evaporation. Fourier transform infrared (FTIR) spectroscopy confirmed the complexation and miscibility between PVAc and PVC and their interaction with MgO nanoparticles (NP). X-ray diffraction and HR-TEM analyses showed the phase purity of MgO NP with a crystallite size of ~ 18.8 nm and their dispersion in the amorphous regions of the blend without affecting the structure of each other. UV–vis-NIR spectroscopy revealed that the band gap of the blend can be tuned by changing the added ratio of each polymer, and loading MgO NP increased the semiconducting behavior of the blend. Various optical constants such as the refractive index, absorption index, and optical dispersion parameters have been evaluated. The blend composition and effects of MgO content on the stress–strain behavior were studied. The addition of MgO to the blend enhanced the tensile modulus and strength. However, there was a corresponding decline in toughness and elongation at break. These results reflect the reinforcing effect of MgO NP, which reduces the flexibility of the polymer chains. The antibacterial activities of MgO/PVAc/PVC PNCs against Staphylococcus aureus, Escherichia coli, and Candida albicans fungi are studied. The improvements in optical, mechanical, and anitmicrobial properties make these nanocomposites suitable for some optical devices and in food packaging applications.