Polymer Network Architecture of Single Network and Semi-Interpenetrating Network Hydrogels Modulates Water Retention and Degradation in Soil Conditioning Applications.

With the global population projected to reach 9.7 billion by 2050, agricultural systems must address challenges related to soil fertility, water retention, and sustainability. To address these issues, biobased hydrogels made from natural polymers, such as gelatin methacrylate (GelMA) and chitosan (CS), have shown promise as sustainable soil conditioners. This study investigates GelMA/CS-based semi-interpenetrating network (semi-IPN) hydrogels, evaluating their swelling capacity, water retention, mechanical properties, and degradation behavior compared to GelMA-only hydrogels. The results show that semi-IPNs with higher CS concentrations exhibit superior water retention and faster degradation rates, alongside enhanced mechanical strength. Scanning electron microscopy reveals smaller, uniform pores in semi-IPNs, contributing to improved water retention. These findings suggest that GelMA/CS semi-IPNs are promising, biodegradable alternatives for enhancing soil moisture retention, soil fertility, and environmental sustainability in agriculture.