In recent decades, the continuous depletion of fossil fuels and the increasingly serious environmental issue have aroused wide attention on the development of biopolymers based on renewable biomass. Lignin is the second most abundant organic bio‐based macromolecule second to cellulose, and it can be widely found in plants. Furthermore, various phenol derivatives can be obtained by their depolymerization processes. The development of bio‐renewable polymeric materials originating from lignin‐derivative phenol monomers, such as vanillin, syringaldehyde, eugenol, vanillyl alcohol, vanillic acid, and ferulic acid, will not only valorize the bio‐sourced materials but also effectively reduce petroleum resource consumption and mitigate the environmental pollution. Therefore, an updated overview of the synthesis processes of these bio‐based polymers developed in the past decade, which includes both thermosets and thermoplastics such as epoxy, phenolic, polyimine, polybenzoxazine, polyurethane, and polyesters, are elucidated. In addition, the applications of these bio‐based polymers and their composites in flame‐retarded materials, degradable and reprocessable materials, dielectric materials, optoelectronic materials, as well as smart responsive materials are also intensively discussed. In line with the gradual development of synthesis technologies, we believe that derivatives of lignin will turn into one of the most promising materials to be considered for the preparation of high‐performance and functional bio‐based polymer materials.

In this work, PVA nanocomposite films containing cellulose nanocrystals (CNC) and different amounts of lignin nanoparticles (LNP), prepared via a facile solvent cast method, were crosslinked by adding glutaraldehyde (GD). The primary objective was to investigate the effects of crosslinker and bio-based nanofillers loading on thermal, mechanical, antioxidant and water barrier behaviour of PVA nanocomposite films for active food packaging. Thermogravimetric analysis showed improved thermal stability, due to the strong interactions between LNP, CNC and PVA in the presence of GD, while Wide-angle X-ray diffraction results confirmed a negative effect on crystallinity, due to enhanced crosslinking interactions between the nanofillers and PVA matrix. Meanwhile, the tensile strength of PVA-2CNC-1LNP increased from 26 for neat PVA to 35.4 MPa, without sacrificing the ductility, which could be explained by a sacrificial hydrogen bond reinforcing mechanism induced by spherical-like LNP. UV irradiation shielding effect was detected for LNP containing PVA films, also migrating ingredients from PVA nanocomposite films induced radical scavenging activity (RSA) in the produced films in presence of LNP. Furthermore, PVA-CNC-LNP films crosslinked by GD showed marked barrier ability to water vapour.