Fabrication and characterization of carbon-based nanocomposite membranes for packaging application

Abstract: The research encompasses on a comparative study of biodegradable membranes based on poly(vinyl alcohol) (PVA), starch (St), graphene oxide (GO) and reduced graphene oxide (rGO) for food packaging application. Four different concentrations, i.e., 10, 20, 30 and 40 mg, of GO and rGO were incorporated in membranes using in situ and ex situ reduction technique. The aim was to enhance the antibacterial and mechanical properties of PVA/St membranes. PVA/St membranes having 20 mg of in situ reduced graphene oxide (PVA/St/IrGO20) exhibited an exceptional tensile strength of 22.719 MPa and outstanding antibacterial activity, i.e., 38.89 ± 0.23 mm and 37.52 ± 0.41 mm, against Escherichia coli and Methicillin-resistant Staphylococcus aureus, respectively. The membranes were also analyzed by scanning electron microscopy (SEM), X-ray diffraction, Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). SEM results revealed the dense morphology for all membranes. FTIR results displayed the successful synthesis of GO, rGO and nanocomposite membranes. The TGA showed that IrGO membranes were more stable as compared to neat and graphene oxide membranes. Moreover, the membranes degraded completely after being buried in the soil. Among all the synthesized membranes, PVA/St/IrGO20 and PVA/St/XrGO10 (PVA/St containing 10 mg ex situ reduced GO) exhibited excellent barrier against water vapor and oxygen transmission. Therefore, they prolonged the shelf life of packed gooseberries as compared to all formulated membranes. Graphic abstract: [Figure not available: see fulltext.]