absorbent fibers have been employed for years in articles ranging from diapers to surgical sponges. initially, these products made use of cellulosic fibers solely as their absorbent material the superabsorbent material absorbs a considerable amount of fluid, and, because of its unique structure, is able to retain a substantial quantity of fluid in its polymer network, significantly more than what could be held in conventional absorbent fibers. the search for new superabsorbents finally led to the development of totally synthetic polymers and modified natural hydrogels. typical natural superabsorbents consists of modifications of guar gum, xanthan gum, or chitin, while the synthetic superabsorbents are typically produced by the polymerization of acrylic acid, acrylate esters, vinyl alcohol, ethylene oxide, acrylamide, and other vinyl monomers with subsequent cross-linking of the resultant polymer. this chapter deals with synthetic and modified natural hydrogel superabsorbents only. 69 refs