Preparation and Properties of Antimicrobial Poly(butylene adipate-co-terephthalate)/TiO2 Nanocomposites Films

Abstract

Poly(butylene adipate-co-terephthalate) (PBAT) nanocomposite films with various contents of nano-titanium dioxide (TiO₂) and titanium dioxide doped silver (Ag-TiO₂) were prepared by a solvent casting method. The TiO₂ and Ag-TiO₂ nanoparticles were surface-modified with silane coupling agents to improve their compatibility and dispersibility in the PBAT matrix. They were denoted as mTiO₂ and mAg-TiO₂, and were characrterized by Fourier transform infrared (FTIR) spectroscopy and transmission electron microscopy (TEM). The morphology of the PBAT nanocomposite films was studied by field emission scanning electron microscopy (FE-SEM). The crystallinity of the PBAT film increased upon the introduction of the nano-TiO₂/Ag-TiO₂. Its mechanical properties and gas barrier properties were also significantly improved. In addition, the PBAT/mTiO₂ and PBAT/mAg-TiO₂ nanocomposite films showed a strong antibacterial activity against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) food-borne pathogenic bacteria.