Lignin‐Based Hydrogels: Recent Advances in Design Strategies, Functional Properties, and Emerging Applications

ABSTRACT

The evolution of eco‐friendly materials, particularly the synthesis of high‐performance lignin‐based hydrogels (LBHs) from degradable biomass feedstocks, is essential and has gained global attention. As an aromatic polymer derived from numerous natural biomass sources, lignin is renewable, recyclable, non‐toxic, broadly functional, and affordable. The physicochemical properties of lignin are related to its functional groups, but they cannot be equated. This article focuses on newly developed materials and applications that can advance progress in environmentally challenging industries. The high‐water‐absorption capability, strong mechanical stability, biocompatibility, conductivity, and adhesiveness demonstrated by lignin hydrogels make LBHs more easily usable. This review article briefly outlines the specialized lignin and the essential elements of LBHs, including their preparation methods, properties, applications, challenges from the laboratory to the commercial scale, and future prospects.