Abstract
Hydrogels are crosslinked hydrophilic polymer chains forming a three-dimensional network that are capable of absorbing large amounts (swelling) of water (up to 99% in weight or more in certain cases). In addition, hydrogels can swell, shrink, bend and curl in respond to external stimuli, such as pH, solvent, temperature, electric field etc. Hydrogels have versatile applications in many fields because of their biocompatibility, swelling characteristics, and stimuli-responsiveness. They are used in hygiene products, household articles, cosmetics, agriculture, and sensing devices. Medical applications include contact lenses, assay-media, wound dressings, drug delivery systems, and artificial organs. Mechanical properties of hydrogels are very important factor in determining their application. Mechanical characterization of the hydrogel network also provides a good understanding of its microstructure. In this communication, we report in situ rheological response of a cationic hydrogel during the formation of 3-dimensional network and characterization of its equilibrium elastic response.