Hybrid Superabsorbent Polymers as "Water Reserve" in Agricultural field

In this study, acrylate-based SAP powder is analysed "as it is" (pristine SAP) and processed with silicate sodium (hybrid SAP) as "water reserve" in agricultural application. To do that, SAP powder is opportunely swelled in different aqueous alkaline media (NaOH or SiO2/Na2O) with a ratio SAP: water solution equal to 1:200. The produced hydrogels properties, such as water retaining and water adsorption/desorption capability along with the regeneration of pristine and hybrid samples are assessed without and within soil in a reduced scale. Furthermore, hydrogels are tested in a real scale system too and the water release is monitored over time starting from dried soil. The results show that hydrogels obtained with 0.5w/w% of SAP can release gradually water to the soil and/or to the plants when needed, more or less in 5 days in relation to environmental conditions, T=26°C and RH=50%. The adoption of the suggested SAP in cultivations could therefore represent a valid approach for the rationalization of water resources, mainly in desert areas or as "monitored water source" in flowerpots located within the "future smart cities"in which the concept of water efficiency represents a fundamental concept.