Preparation of Superabsorbent Polymers for Use as Soil Moisture Holder in Agriculture: A Green Synthetic Route

Superabsorbent polymers (SAPs) are lightly cross-linked hydrophilic polymers that can absorb, swell and retain aqueous solutions up to hundreds of times their own weight [1].Common SAPs are generally white sugar-like hygroscopic materials, which are mainly used in disposable diapers and other applications including agricultural use and soil conditioning and as artificial soils for hydroponics, as controlled release agents for agrochemicals or pharmaceuticals, as artificial snow for skiing areas, and other numerous applications [2].In agriculture, superabsorbent polymers are used as a soil additive, as reservoir of nutrients, and as water superabsorbent in the soil.Superabsorbent polymers are used as water adsorbents to increase the capacity of the soil to absorb and retain water and this property is very important to encounter the impacts of dehydration and reduce impacts of drought stress in crops.These materials decrease the number of irrigation times by increasing the gaps of irrigation, therefore the water cost and energy will be saved [3]. In the present work, a class of superabsorbents was synthesized with different ratios of two monomers,acrylicacid and acrylamide,with a water-soluble crosslinker (N,N’-methylenebis (acrylamide), MBAAm)in aqueous medium.The performance of the prepared superabsorbents such aswater-holding capacity (WH) and water-retention ratio (WR) was investigated in soil samples.Other analyses such as swelling,FT-IR,TGA and SEM were alsostudied.Results showed acceptable efficiency for the prepared samples. It can be concluded that the prepared samples could be a good additive foragricultural soils as moisture holder.