Green fabrication of nanocomposite films using lignin nanoparticles and PVA: Characterization and application

In this study, we adopted the anti-solvent method to synthesize LNPs using a deep eutectic solvent (DES). We evaluated the dispersibility, particle size, and zeta-potential of the LNPs and observed that they have a particle size distribution of 586-848 nm and showed excellent dispersion and stability. FT-IR and UV were used to demonstrate that the formation mechanism in LNPs mainly involved pi-pi stacking forces, and functional groups were not changed. The PVA/LNPs nanocomposite films were fabricated, and their structural and functional behavior were analyzed. The results demonstrated that LNPs were uniformly distributed in the nanocomposite films and formed strong hydrogen bonding interactions with PVA, which improved the thermal stability, mechanical properties, and hydrophobic properties of the nanocomposite films. Notably, LNPs impart the films with excellent UV shielding properties, outstanding antioxidant efficacy, and effective antibacterial activity against S. aureus and E. coli, which makes PVA/LNPs nanocomposite films a potential option for active food packaging.