Abstract:In this study, nano-titanium dioxide was incorporated into polyvinyl alcohol, and polyvinyl alcohol active films with different concentration of nano-titanium dioxide (0.0%, 0.5%, 1.0%, 3.0%, 5.0%, and 7.0%) were prepared by solution casting method. The moisture absorption and antimicrobial properties of polyvinyl alcohol films modified with nano-titanium dioxide was studied. The hygroscopic properties of the films were studied through isothermal hygroscopicity experiments, and the experimental data were fitted and characterized based on GAB isothermal hygroscopic model. The antimicrobial properties of the films were analyzed through the growth inhibition experiments of Staphylococcus aureus and Escherichia coli, respectively. The results showed that nano-titanium dioxide could give excellent hydrophobicity to polyvinyl alcohol films. The hygroscopicity of the films was decreased with the increasing addition of nano-titanium dioxide, and when the relative humidity was 11%, 33%, 57%, 75% and 84%, respectively. Compared with pure PVA films, the equilibrium moisture content of polyvinyl alcohol films containing 7% nano-titanium dioxide was significantly reduced by 1.53%, 3.97%, 4.10%, 7.20%, and 10.70%, respectively (P<0.05). The hygroscopicity of polyvinyl alcohol active film incorporated with different concentration of nano-titanium dioxide could be fitted by GAB isothermal moisture absorption model, and the model's fitting R2 was all above 0.99. The overall variation trend of the GAB isothermal adsorption model curve of the six PVA active films was similar, which belonged to the type II isothermal moisture absorption curve. The antimicrobial properties of the polyvinyl alcohol film were modified by adding nano-titanium dioxide. The OD595 growth trend of S.aureus and E. coli colonies decreased with the increase of the nano-titanium dioxide concentration in the film. The polyvinyl alcohol film modified with nano-titanium dioxide had good hydrophobicity and antibacterial performance, indicating that it might have a beneficial effect in the storage process of food packaging, and provide a reference basis for the future research and development of food packaging preservation technology.