Derivatization of Lignin via Ternary Eutectic Solvent Systems for Enhanced Functionalities Hydrogel.

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Sustainable Materials

Background:

• Lignin, a complex biopolymer, presents challenges in structural modification and functionalization.
• Developing advanced hydrogels with high water absorption and stability is crucial for various applications.

Purpose of the Study:

• To present a novel strategy for lignin derivatization and hydrogel formation.
• To characterize the properties and water absorption behavior of the resulting lignin-based functional hydrogel (LBFH).
• To explore the potential applications of LBFH in agriculture and environmental remediation.

Main Methods:

• Lignin structural modification using a ternary eutectic solvent system (TESS) for targeted derivatization.
• Preparation of lignin-based functional hydrogel (LBFH) through rational cross-linking of derivatized lignin.
• Analysis of water absorption kinetics using Schott kinetics and Fickian diffusion models.
• Evaluation of hydrogel stability under atmospheric conditions.

Main Results:

• The developed LBFH exhibited exceptional hygroscopic properties with a water swelling ratio of 934.0%.
• Water absorption kinetics were elucidated by dual-modeling, revealing synergistic adsorption and diffusion processes.
• LBFH demonstrated remarkable environmental stability, retaining 48.6% water after 7 days at 25 °C and 60% RH.

Conclusions:

• The novel TESS-based modification strategy effectively yields functional lignin-based hydrogels.
• LBFH possesses superior water absorption and retention capabilities, surpassing many biopolymer hydrogels.
• Engineered LBFH holds significant potential as drought-resistant soil amendments and contaminant-adsorptive matrices for sustainable applications.