Influence of Biochar on the Properties of Antibacterial PBAT/Carvacrol Films

In recent years, there has been an increasing interest in antibacterial biopolymeric films. Among the different approaches for tuning the release kinetic of antibacterial compounds, the use of natural fillers allows for this purpose while optimizing the processability and the mechanical properties of the products. In this work, the effect of three different concentrations of biochar (BC) was investigated on the morphological, rheological, mechanical, and thermal properties of Polybutylene adipate terephthalate/Carvacrol/BC (PBAT/CV/BC) ternary biocomposites. The films were fabricated by means of melt mixing and compression molding and compared to PBAT/BC samples. The carvacrol kinetic release was evaluated as a function of the BC concentration in the ternary system. Results highlighted that BC allows tuning the properties of PBAT and of PBAT/CV samples and modifying the release kinetic of CV. Finally, the antimicrobial analysis revealed that PBAT/CV films exhibited excellent antimicrobial properties against Escherichia coli, Listeria monocytogenes, Salmonella Enteritidis, and Staphylococcus aureus.