Active packaging film based on a green composite: fabrication and performance analysis of pineapple leaf fiber-reinforced PBAT

To achieve the high-value utilization of pineapple leaf waste and to develop green preservative materials, pineapple leaf fiber ultrafine powder (PLFUP) was prepared through oscillatory ultrafine grinding, and PLFUP/PBAT composite films were subsequently fabricated via twin-screw extrusion blending followed by single-screw blow molding. The films were evaluated for surface microstructure, thermal properties, gas barrier performance, and degradability, and their effects on mango preservation were also investigated. The results indicated that the optimal grinding time for PLFUP was 10 minutes, yielding a particle size of 49 µm. As the PLFUP content increased, the surface roughness of the composite films increased, while the glass transition temperature, crystallinity, and melting enthalpy decreased. In contrast, the cold crystallization and melting temperatures rose. Furthermore, both water vapor permeability and oxygen permeability increased significantly, and the biodegradation rate was accelerated. When a composite film containing 3% PLFUP was used as a sealed preservation bag, the mangoes exhibited the fewest surface lesions, along with superior color and gloss, demonstrating the best preservation performance. This study successfully developed a functional packaging film with natural antibacterial activity, tunable permeability, and high biodegradability, offering a novel approach for the resource utilization of agricultural by-products and the advancement of eco-friendly fruit and vegetable preservation technologies.