Stimuli responsive hydrogel composite materials for potential environmental and biological applications

Abstract

The prevailing dissertation focuses on a detailed investigation of hydrogels to comprehend the unexplored fundamental aspects of morphology, swelling, binding mechanism, and stimuli-response behavior of the prepared nano and micro structured hybrid hydrogels and to expand the range of their applications in the environmental and biological fields. In this study, CS was employed as a base constituent to prepare the hydrogels and hybrid hydrogels. Nanoparticles (Fe2O3, ZnO, and Ag), graphene oxide (GO), glutaraldehyde (GA), N-isopropylacrylamide (NIPAM), methacrylic acid (MAA), and PNIPAM microgels were used as a other active constituents. For the preparation of hybrid hydrogels, the sol-gel and free radical polymerization methods were employed. The binding mechanism, morphological features, elastic and thermal properties of the prepared hydrogels were investigated in detail using different physical characterization techniques. The higher surface area and number of oxygen-containing functional groups of GO were found to have a significant impact on the adsorption process of dye molecules onto the GO-based hybrid hydrogels. Furthermore, the results obtained from TGA measurements reveal that GO increased the thermal stability of the hydrogels by forming a compact structure via covalent and electrostatic interactions with the polymer moieties. The impact of GO was also studied in the case of drug delivery systems, where the release profile of the hybrid hydrogels down and prolonged due to the strong electrostatic interaction between the oxygen-containing functional groups of GO and drug molecules. newline