Mechanical, Barrier, Adhesion and Antibacterial Properties of Pullulan/Graphene Bio Nanocomposite Coating on Spray Coated Nanocellulose Film for Food Packaging Applications

In this study, an environmentally friendly and biodegradable pullulan/graphene bio nanocomposite was prepared and coated on the nanocellulose film to improve the surface, mechanical, barrier and antibacterial properties. The nanocellulose films were prepared by using a spray coating of nanocellulose suspension on stainless steel plates. The graphene nanoparticles were prepared by modified Hummers method. The pullulan/graphene bio nanocomposites were prepared by solvent method with the addition of various wt% (0, 0.05, 0.1, 0.2) of graphene with pullulan. The coating was carried out by roller coating method. Results showed that the increased graphene nanoparticles in pullulan coating increased the opacity, surface hydrophobicity, tensile strength, oxygen transmission rate and watervapour transmission rate of the coated nanocellulose film. Also, the coated film showed excellent antibacterial properties against both gram-negative E. coli and gram-positive S. aureus. In this research work, it was concluded that the graphene nanoparticles of 0.2 wt% showed efficient results. The exceptional properties of the pullulan/graphene bio nanocomposite coating on the nanocellulose film will give a new pathway to high performance food packaging applications.