A Synergistic Approach to Sustainable Packaging: Exploring Mater-Bi®/PHBV Multilayer Systems

In this study, multilayer films were produced using a co-extrusion process involving two complementary bioplastics: Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and Mater-Bi^®. PHBV is recognized, among biodegradable polymers, for its excellent oxygen barrier properties, but is also known for being brittle, non-sealable, and difficult to process. Conversely, Mater-Bi^® has good processability, low stiffness, and high ductility, but exhibits poor barrier properties. The research investigated the barrier, mechanical, sealing, and optical properties of the films to evaluate how variations in layer structure and processing parameters influenced their overall performance. The results showed that the addition of the PHBV layer, both as a neat polymer and as a blend with Mater-Bi^®, significantly reduced oxygen and water vapor permeability. Additionally, Mater-Bi^® was found to be essential for providing the elasticity and sealability required for the multilayer films. The study also demonstrated that layer thickness plays a critical role in property tailoring.