A novel Iraqi Prunus Domestica gum and lignin as natural precursors for the development of hydrogels for the slow release of thiamethoxam

Abstract

Sustainability, which addresses the challenges of agricultural issues, requires the development of hydrogel-based systems. For this purpose, new hydrogels have been synthesized via free radical copolymerization using Iraqi Prunus domestica gums (IPDG) and lignosulfonic acid sodium salt (LS), and were analyzed by FTIR, ¹³C NMR, FESEM, XRD, and TGA techniques. The swelling capacities are 165.357 g.g⁻¹ of LS-IPDG-g-SAH, 159.267 g.g⁻¹ of LS-g-SAH, and
156.469 g.g⁻¹ of IPDG-g-SAH hydrogel formulations. The pH 7.2 exhibited the maximum swelling in distilled water compared to alkali and acidic media. The release behavior of thiamethoxam in distilled water has been modeled using the Korsmeyer–Peppas, Weibull, and Higuchi models. Up to 92 h, 27.793%, 25.447%, and 23.538% of the pesticide are released from LS-IPDG-g-SAH, LS-g-SAH, and IPDG-g-SAH, respectively. For soil application, the trend of water evaporation is in the decreasing sequence: blank soil > IPDG-g-SAH >LS-g-SAH >LS-IPDG-g-SAH after 12 days. These results generally present the prospects of hydrogels as environmentally friendly materials for agrochemical applications, providing opportunities for the controlled delivery of pesticides and increased resource efficiency. Additionally, the novel approach by incorporating IPDG and lignin-based hydrogels makes it of fantastic value in the field of potential agricultural development.