Poly(vinyl alcohol)-Based Composite Film with Integrated Sustainability, Biodegradability, and Multifunctional Properties

The widespread use of petroleum-based plastics has caused severe pollution to global ecosystems. Therefore, the development of sustainable and biodegradable eco-friendly materials is urgently needed. This study successfully prepared a multifunctional composite film (PVA-FA/TA) by introducing functional folic acid (FA) and tannic acid (TA) into poly(vinyl alcohol) (PVA) via hydrogen bonding cross-linking. Results indicate that the PVA-FA/TA4 composite film exhibits shielding efficiencies of 99.998 and 100% against UVA and UVB radiation, respectively, while maintaining high transparency in the visible spectrum. Furthermore, the composite film demonstrates remarkable free radical scavenging capabilities, achieving maximum DPPH and ABTS radical scavenging rates of 94.27 and 95.29%, respectively. Moreover, the PVA-FA/TA composite film demonstrated significant antibacterial effects against both Escherichia coli and Staphylococcus aureus. Beyond functional advantages, the PVA-FA/TA composite films are recyclable and reusable, reducing resource waste. Most importantly, complete degradation occurs within 100 days when discarded in soil, further mitigating environmental pollution. Overall, this study provides a feasible and scalable approach for designing next-generation functional film materials with comprehensive protective capabilities.