الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Hydrogels are defined as crosslinked polymer networks that absorb substantial amounts of aqueous solutions and cover a high number of hydrophilic groups or domains. Certain materials, when placed in a compatible aqueous medium, are able to swell and preserve the volume of the adsorbed aqueous medium in their 3D swollen network, giving the hydrogel its form1. These networks have a high affinity for water, yet are kept from dissolving due to the chemical or physical bonds formed between the polymer chains1. In a simple binary system of a polymer and a liquid; when the polymer–liquid interaction is more favored than both polymer–polymer and liquid–liquid interactions, a sol is formed. If the polymer is hydrophilic and the liquid is water, the polymer–liquid interaction formed is called a hydrosol. The extent of this reaction is mostly dependent on the polymer structure, functional groups, type, and amounts of ions in the polymer structure as well as in the solution, pH, and temperature. A crosslinked hydrosol is known as “hydrogel” and can only swell in the surrounding liquid to a certain swelling ratio depending on the number of crosslinks, i.e., the crosslinking density2.