2.1.8.2. Absorbency Under Load (AUL) - BADA

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INTRODUCTION
Superabsorbent hydrogels are crosslinked, hydrophilic polymers which can absorb and keep a
large amount of water or biological fluids in their polymeric structures and shrink after de-
swelling.
Substantial amount of research has been reported on the properties of superabsorbent hydrogels,
particularly on the pH, temperature and sensitivity to ionic strength. A variety of novel aspects of
superabsorbent polymers (SAP) also have been investigated. These include cosmetic and toiletry
formulations [1] , immobilized enzyme in reactors [3] , contact lens materials [4] , water-retention in
agricultural and horticultural soil [1] , flocculation agents [1] , liquid radioactive wastes treatment [9] ,
sensors [1] and many other applications.
Two types of polymers, biodegradable and non-biodegradable polymers, are used for providing
of superabsorbent polymers (SAPs) for many applications. The biodegradable hydrogels are
usually made from natural polymers such as proteins, chitosan, poly-lactic acid (PLA), poly-
glutamic acid, hyaluronic acid and some cellulose derivatives. The non-biodegradable hydrogels
are made from synthetic materials, such as acrylic acid polymers, poly-vinylalcohol, poly-
methylmetacrylates, poly-vinylpyrrolidone, poly-acryl amide and poly-vinyl acetate. The non-
biodegrable synthetic hydrogels show several properties for different purposes, but remaining the
number of monomers in final products can create some serious problem for human body and
environment.
Recently the term of biodegradation and non-toxic polymers have been introduced as main goals
in the development of new technology. In this manner, non-toxic biodegradable hydrogels have
been studied extensively for biomedical applications such as bio-adhesive, wound dressings for
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