Alkaline-Enhanced Poly(Acrylic Acid)/Sodium Alginate/PEO Hydrogels: Structural Modifications and Functional...

Area of Science:

• Materials Science
• Polymer Chemistry
• Agricultural Engineering

Background:

• Hydrogels are crucial for water management, but their performance needs optimization.
• Acrylic acid (AAc), sodium alginate (SA), and poly(ethylene oxide) (PEO) hydrogels are synthesized using electron beam irradiation.
• Modulating hydrogel properties is key for enhanced functionality.

Purpose of the Study:

• To investigate the effect of alkaline (NaOH) treatment on AAc/SA/PEO hydrogels.
• To assess the impact of NaOH concentration on hydrogel swelling, biodegradability, and water retention.
• To optimize hydrogel performance for agricultural water management.

Main Methods:

• Hydrogel synthesis via 5.5 MeV electron beam irradiation.
• Alkaline treatment using 0.25 M and 0.50 M NaOH solutions.
• Characterization using FTIR, SEM, TGA/DSC, and evaluation of gel fraction, cross-linking density, mesh size, porosity, swelling kinetics, and water retention.

Main Results:

• FTIR and SEM confirmed structural changes and increased porosity post-treatment.
• Thermal stability significantly increased, with T-onset rising from 236 °C to 451 °C.
• 0.25 M NaOH treatment optimized mesh size, porosity, and swelling capacity (428 ± 14 g/g), while 0.50 M induced degradation.

Conclusions:

• Alkaline treatment offers tunable modification of hydrogel properties.
• Optimized hydrogels demonstrate accelerated water uptake and improved rainwater retention.
• These modified hydrogels show significant potential for agricultural water management applications.