Development of polyvinyl alcohol/chitosan/pullulan blended films incorporated with tea extract-synthesized TiO₂...

In recent years, nanoparticle-infused biopolymeric films have emerged as promising alternatives to non-biodegradable synthetic packaging that poses significant environmental concerns. This work aims to develop and characterize biopolymeric films for food packaging applications using polyvinyl alcohol (PVA)/Chitosan (CS)/Pullulan (PL) incorporated with TiO₂ nanoparticles (NPs) synthesized using tea leaf extract. PVA/CS/PL (1:0.5:0.5) films were developed with varying concentrations of TiO₂ NPs (0.5, 1, and 1.5 wt%), and their effects on the films' physical, thermal, transmission, mechanical and antibacterial properties were investigated. The results show that the addition of TiO₂ NPs improve the film's thermal stability and mechanical strength. The addition of TiO₂ NPs (<1 wt%) greatly increased the tensile strength of the bio-composite films while simultaneously lowering their gas barrier properties. However, increasing the TiO₂ NP percentage (>1 wt%) further enhanced the film's gas barrier properties while decreasing its tensile strength. The antibacterial efficacy of these bio-composite films was confirmed by an antimicrobial assay against E. coli. These findings provide a pathway for the value-added utilization of tea extract polyphenols and highlight the potential of TiO₂-incorporated PVA/CS/PL biodegradable polymer film as a promising candidate for green food packaging applications.