Superabsorbent Hydrogels Derived from Cellulose Obtained from Post-Consumer Denim.

Area of Science:

• Materials Science
• Green Chemistry
• Sustainable Engineering

Background:

• Conventional hydrogel production often relies on virgin materials and harsh chemicals.
• Valorization of textile waste, specifically post-consumer denim, remains a significant challenge.
• Developing sustainable alternatives for cellulose-based materials is crucial for a circular economy.

Purpose of the Study:

• To present a novel, circular-economy-driven strategy for converting waste denim into high-performance hydrogels.
• To demonstrate an eco-friendly, integrated process without intermediate purification steps.
• To explore the potential of these hydrogels in agricultural and environmental applications.

Main Methods:

• High-energy mechanochemical pretreatment of recycled denim to reduce particle size and crystallinity.
• In situ carboxymethylation of denim cellulose to produce carboxymethylcellulose (CMC).
• Citric acid and urea-based crosslinking to form a 3D hydrogel network with tunable porosity.

Main Results:

• Mechanochemical treatment reduced denim crystallinity from 75.7% to 66.1%, enhancing reactivity.
• FTIR confirmed successful CMC synthesis and citric acid crosslinking.
• Hydrogels exhibited tunable porous morphology (up to 147 µm pores) and enhanced thermal stability.
• A hydrogel formulation achieved an exceptional swelling capacity of 1900%.

Conclusions:

• Waste denim can be directly converted into functional hydrogels through an integrated, eco-friendly process.
• The developed hydrogels show promise for sustainable agricultural applications like soil water retention.
• This approach offers a scalable solution for textile waste valorization within a circular economy framework.