Boron Nitride-Based Polyester Nanocomposite Films with Enhanced Barrier and Mechanical Performances

Developing sustainable plastics, for instance, green poly(ethylene 2,5-furandicarboxylate) (PEF), is a promising pathway to decrease the reliance on petroleum-based plastics and the pollution of the environment. However, the preparation of high-performance PEF materials that integrate superior barrier and mechanical properties remains a huge challenge. In this study, a BNNSs/PEF composite film with excellent mechanical and barrier performance was fabricated by using furfuryl alcohol simultaneously acting as a high-level dispersant and interfacial reinforcement matrix for BNNSs. The optimized BNNS/PEF composite film with 0.2 wt % BNNSs (BP2) shows a compacted aligned structure and excellent comprehensive performance with 79.2 MPa tensile strength (43% enhancement), 4.2 GPa Young’s modulus (83% enhancement), high gas barrier, and enhanced thermal stability. Remarkably, fruit testing conditions (e.g., relative humidity of 90–95%, temperature of 30, and natural light) showed that the BP2 composite film extended the shelf life of fresh strawberries by at least at least 5 days in an ambient environment. The overall performance of the BP2 composite film is optimized to be superior, which opens up an avenue for practical applications in the field of packaging materials.