Core-shell hydrogels: Robust interfacial integration and extreme environmental tolerance enabled by lignin nanoparticles

Hydrogels exhibit broad application potential in fields such as soft functional materials. This study designed Core-Shell composite hydrogel material (AM) based on double-bond functionalized hyperbranched lignin nanoparticles (DH-LNPs), achieving synergistic regulation of multifunctional and mechanical stability through a “Core-Shell” strategy. DH-LNPs, serving as multifunctional modifiers, form covalent bonds between the high-toughness polyacrylic acid-based shell and the flexible, self-healing TEMPO-oxidized nanocellulose/guar gum core hydrogel, thereby enhancing interfacial bonding. This core-shell architecture significantly improves both structural integrity and environmental tolerance. The hydrogel demonstrates outstanding comprehensive properties: the resulting AM-4 hydrogel exhibited self-healing ability and strong adhesion to a variety of substrates, with high mechanical toughness (3428.9 kJ·m −3 ) and an outstanding UV shielding efficiency of 99.1 %. This study provides new insights for the design of soft functional materials in extreme environments, while expanding the application potential of lignin nanoparticles in high-performance bio-based materials.