Structure and properties of starch/chitosan food packaging film containing ultra-low dosage GO with barrier and antibacterial

Using urea as an intermediate, graphene oxide (GO) was modified with carboxymethyl cellulose (CMC) to obtain a uniformly dispersed GO monolayer dispersion for starch/chitosan composite preparation films. The structure and properties of modified GO and starch/chitosan composite films were characterized by FTIR, XRD, and TG. It was found that the modified GO could form a single layer uniformly and stably dispersed in the starch/chitosan composite film. At low GO content (0.01 wt%), the tensile properties of the films increased by 91.7% to 62.5 MPa compared with the control group, the water vapor permeability (WVP) was low, the water resistance was good, and the UV shielding effect was maintained at 92% under 50% visible light. At the same time, the film changed from overflow antibacterial mode to contact antibacterial mode. The antibacterial ability against Escherichia coli and Staphylococcus aureus increased by 23.8% and 25.6%, respectively, compared with the control group. It has an apparent preservation ability for fresh fruit. These excellent characteristics can be widely used in food packaging and pharmaceutical fields.