Biodegradable packing food films based on PBAT containing ZnO and MoO3

Abstract

AbstractMolybdenum trioxide (MoO3) and zinc oxide (ZnO) were incorporated into the poly(butylene adipate‐co‐terephthalate) (PBAT) matrix using casting method to obtain packing films for food transportation with outstanding properties and no formation of microplastics. Consequently, these films were evaluated using Fourier transform infrared spectroscopy, time domain and carbon‐13 nuclear magnetic resonance, x‐ray diffraction, contact angle measurement, and thermogravimetric analysis. The light barrier properties of the films were analyzed using transmittance mode in UV–VIS–NIR regions and the contact angle of composite films exhibited greater hydrophilicity compared to the pure polymer films. Regardless of the concentration, the fillers did not significantly modify the degradation onset temperature and the temperature of maximum degradation rate. However, ZnO caused a new thermal degradation event (around 330°C) that was not observed in the other films, possibly due to the second crystallization process. Composite films filled with 0.3% ZnO, 0.3% and 0.5% MoO3 showed greater molecular homogeneity than the pure polymer matrix, with the PBAT/MoO3 films demonstrating even greater homogeneity than PBAT/ZnO films; this response presumably comes from the satisfactory intermolecular interaction or adequate dispersion and distribution of the particles. The addition of 0.5% MoO3 in the matrix influenced the PBAT film, resulting in amorphous materials with the highest molecular mobility and opacity. Besides, in view of antimicrobial tests, all nanocomposites showed potential bacteriostatic activity. So, it can be conveniently used for food transportation and may avoid microplastic formation, after been discarded.