Hydrophilic polymers, agricultural

Superabsorbents are superabsorbent polymers, which are loosely crosslinked hydrophilic polymers and have ionic charges in the polymers. They absorb water, swell, and retain aqueous solution above hundred times their own weight. Because of the excellent characteristics, the superabsorbents have been widely used in many applications such as disposable diapers, feminine napkins, soil additives in agricultural or horticultural applications, gel actuators, water-blocking tapes, materials for drug delivery system, absorbent pads, etc., where water absorbency or water retention is important. 

Polymer hydrogels are cross-linked hydrophilic polymer networks that are able to swell considerably in an aqueous medium. The development of hydrogels is a dynamic field of research, and these materials could be used in various applications as agriculture, wastewater treatment, and of course biomedicine and pharmacy (drug delivery systems, wound dressing, soft contact lenses, etc.). 

The origins of super absorbent polymer chemistry trace back to the early 1960s when the US Department of Agriculture developed the first super absorbent polymer materials. Sodium polyacrylate belongs to a family of water loving or hydrophilic polymers. It has the ability to absorb up to 800 times its weight in distilled water. Sodium polyacrylate is a powder takes the form of... 

Starch, a well-known hydrocoUoid biopolymer is a low cost polysaccharide, plentifully available and is one of the cheapest biodegradable polymers. It is produced by agricultural plants in the form of hydrophilic granules. Starch is mainly extracted from potatoes, wheat, com, and rice. It is composed of amylose (poly-a-1,4-D-glucopyranoside), a Hnear and crystalline polymer, and amylopectin (poly-a-1,4-D-glucopyranoside and a-l,6-D-glucopyranoside), a branched and amorphous polymer. The relative amounts and molar masses of amylose and amylopectin vary... 

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