Sodium Lignosulfonate-Based Biodegradable Superabsorbent Hydrogel: Fabrication, Characterization, and Application...

Area of Science:

• Materials Science
• Biotechnology
• Polymer Chemistry

Background:

• Superabsorbent hydrogels are crucial for various applications.
• There is a growing demand for sustainable and biobased alternatives to conventional hydrogels.
• Biomass-derived materials offer a promising route for eco-friendly hydrogel synthesis.

Purpose of the Study:

• To synthesize a novel biobased superabsorbent hydrogel using readily available biomass resources.
• To investigate the structural properties and water absorption capabilities of the synthesized hydrogel.
• To evaluate the biodegradability and potential applications of the novel hydrogel.

Main Methods:

• Rapid synthesis of a biobased superabsorbent hydrogel via open-system aqueous solution polymerization.
• Utilized sodium lignosulfonate (SL), sodium alginate (SA), and citric acid (CA) as biomass-derived raw materials.
• Optimized reaction conditions using orthogonal experiments and characterized the hydrogel's properties through various analytical techniques.

Main Results:

• The synthesized hydrogel exhibited outstanding water absorption capacities (313 g/g in deionized water) and excellent centrifugal water retention rates (99.1% in NaCl solution).
• Rapid swelling equilibrium was achieved within 4 minutes in a 0.9 wt% NaCl solution.
• The hydrogel demonstrated superior absorption for artificial urine (64.1 g/g) and artificial blood (117.8 g/g), exceeding commercial products.
• A biodegradation rate of 71.7% was achieved after 28 days of soil burial.

Conclusions:

• The novel biobased superabsorbent hydrogel possesses excellent water absorption, retention, and biodegradability.
• The material's properties meet and exceed relevant national standards for pressurized water absorption.
• This sustainable hydrogel shows promising potential for applications in hygiene products, agriculture, and environmental remediation.