Preparation and characterization of lignin nanoparticles and chitin nanofibers reinforced PVA films with UV shielding properties

Environmental pollution of non-degradable packaging and the increasing demand for biodegradable food packaging materials are driving research on the design and development of multifunctional polyvinyl alcohol (PVA)-based films. However, binary PVA blends are not suitable to satisfy the requirements for mechanical properties, thermal stability, hydrophobicity and UV-barrier properties of food packaging materials. Herein, ternary nanocomposite films have been fabricated by incorporating sustainably renewable chitin nanofibers (ChNF) and biomass-based lignin nanoparticles (LNPs) into the biodegradable PVA. Results suggest that addition of 5 wt% ChNF and 1 wt% LNPs improves the films toughness appreciably along with superior thermal stability and surface hydrophobicity. More importantly, these nanocomposite films are transparent but could shield 95% of the UVB (275–325 nm) and UVC (200–275 nm) radiation. The outcome is deemed to aid developing novel PVA-based for biodegradable food packing materials and UV-shielding biomaterials, and it provides a way to solve the pollution of non-degradable plastics.