Biodegradable PLA/PHBV Polymer Blends for Sustainable Packaging in the Food Industry

Almost half of the global production of fossil-based polymers is used for food packaging, and their resistance to biodegradation leads to significant environmental impacts.Polymers synthesised from renewable sources have become crucial for the development of sustainable packaging materials, particularly in the food industry.Biodegradable polymers such as poly(lactic acid) (PLA) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) have emerged as promising alternatives to conventional polymers.However, due to the limiting properties of the individual polymers, PLA/PHBV blends have been developed to improve their thermal and barrier performance, and to retain their biodegradability.In this study, the properties of PLA/PHBV polymer blends with varying PLA content were investigated.Thermal properties were analysed using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).The morphology of the samples was examined by scanning electron microscopy (SEM), while barrier properties were assessed using the Hoffman method.Changes in chemical structure and interactions between PLA and PHBV were studied by Fourier-transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR).Adhesion-related parameters were indirectly evaluated by measuring surface contact angles and test liquids.The results indicate that PLA/PHBV blends with lower PHBV content exhibit better morphological, thermal, mechanical, and barrier properties than blends with higher PHBV content.The obtained properties of the PLA/PHBV blends provide improved functionality while maintaining environmental compatibility, making them promising formulations for the development of sustainable food packaging.