Comparative Study of the Addition of TiO2 and TiO2/OMMT Clay on the Properties of PBAT for Biodegradable Food Packaging Applications

Microplastics from synthetic polymers significantly impact ecosystems and human health, making biodegradable polymers a promising alternative. To enhance their properties, nanofillers have been widely explored. In this study, TiO2 nanoparticles, alone and combined with B8 OMMT clay, were incorporated into a PBAT matrix to improve its functionality for food packaging applications. Results revealed that nanofillers did not significantly alter PBAT’s crystallinity (Xc ≈ 33%) or thermal stability (Tonset ≈ 375 °C), and the nanocomposites exhibited a predominantly intercalated morphology. Furthermore, low concentrations of nanofillers improved matrix uniformity. Contact angle measurements showed increased hydrophilicity in all formulations, with B8 OMMT systems exhibiting the highest hydrophilicity. The mechanical performance of the PBAT/B8/TiO2 systems was more promising in terms of stiffness, with a 44% increase in Young’s modulus for the PBAT/B8/TiO2 0.5% system. However, all PBAT/B8/TiO2 systems exhibited a more pronounced loss of ductility. Water activity (aW) analysis demonstrated that TiO2 alone reduced aW values to 0.50–0.53, which could potentially enhance biosafety, while the addition of B8 OMMT increased aW to 0.69–0.76, potentially increasing susceptibility to microbial growth. Notably, systems with TiO2 alone showed the greatest potential for food packaging applications due to their increased biosafety, thermal stability, and favorable set of properties.