Rheological investigation of polymer hydrogels for industrial application: a review

Hydrogels are 3 D cross-linked networking of polymeric materials having the capacity to absorb a tremendous amount of water within the network. Many techniques have been introduced for the characterization of synthesized gels. Most common are the spectroscopic methods (UV/Vis, FTIR) used at the molecular and atomic level, diffraction method (XRD) used for measurement of crystallinity within the structure, microscopy (SEM, TEM) to know about the surface texture and morphology and rheology for the elucidation of viscoelastic behavior of hydrogels. Many industries especially pharmaceutical, cosmetic, food processing, agriculture, water treatment, and other related research fields are directly dependent on the rheological characterization of hydrogels for their possible and related application. Similarly, the final design of the product also depends on characterization at a microscopic level to understand the structure and type of interaction within the hydrogel network and its behavior toward the applied external forces. In the present review paper, we have focused on and tried to grip the rheology of synthetic, natural, and semi synthetics hydrogels-based materials and their application in daily life on an industrial scale.