Flexible Lignin-based hydrogels with Self-healing and adhesive ability driven by noncovalent interactions

Flexible and adhesive hydrogels with self-healing abilities have great potential in various fields. In the present study, a new type of self-healing and adhesive hydrogel driven by noncovalent interactions including hydrogen bonds and hydrophobic interactions was readily constructed by mixing lignosulfonate (LS) and polyvinylpyrrolidone (PVP) in water. When the pH value was adjusted to neutral, LS aggregated to form rigid noncovalent junctions and PVP associated with these domains to form a flexible network. A series of hydrogels were obtained by altering the concentrations of LS and PVP. Owing to the unique structure and dynamic and reversible characteristics of the gelation mechanism, the hydrogel exhibited good toughness, and self-healing ability. The abundant active groups and improved cohesion endowed the LS/PVP composite (LPC) hydrogel with good adhesive ability to various substrates. In addition, the LPC hydrogel exhibited excellent biocompatibility. Collectively, these advanced properties allowed the hydrogel to be successfully applied as a hemostatic agent to treat organ injuries. This work provides a new platform for multifunctional lignin-based hydrogel which could be applied in biomaterials.