Naturally sourced polymer-based hydrogels offer advantages over synthetic forms owing to their biocompatibility, physicomechanical and environmentally friendly properties.
A hydrogel is basically a polymer made by cross-linking monomers with an ionic agent such as a strong cation. It can absorb and store large quantities of water in its branched polymer network. While in most cases the cation can be a regular alkali metal, for application is soil, it was essential to consider a cation that can impart non-toxic biodegradable properties to the water absorbing materials. It was coincidentally identified that potassium is a necessary alkali metal in soils that stimulates plant growth without polluting soil components. This led to a new application perspective of a 2in1 application of hydrogel in agriculture as well as a soil conditioner.
The need for more arable land in view of increasing agricultural production has renewed interest in the development of novel soil conditioner materials with new methods and lower rates of application. Hydrogel is basically a water absorbing polymers, which are classified as cross-linked, absorb aqueous solutions through hydrogen bonding with water molecules. Agricultural hydrogels are referred to as water retention granules because they swell to many times their original size when they come in contact with water.