Preparationand Characterization of pH-Sensitive Hydrogels Based on Crosslinked Maleic Anhydride-Styrene-Methyl Methacrylate Terpolymer

Inthis study, the hydrogels have been synthesized by the crosslinking reactions maleicanhydride-styrene-methyl methacrylate terpolymer with N, N'-methylene-bis-acrylamide and glutaraldehyde in variouscrosslinker ratios. Crosslinking reactions were carried out in the presence of tetrahydrofuranas solvent at 25-50ºC for different time period, and the resulting materialproperties compared. The best conditions for effective crosslinking, i.e., crosslinkingtemperature, time and crosslinker ratios were determined for each crosslinkertype. The swelling behaviour of the hydrogels was examined in Tris-buffersolutions at various pH at 37ºC. Swelling depending on pH was observed in thehydrogels. The pH-dependent swelling of hydrogels was strongly influenced bythe functional group of crosslinker. The molecular structure of the hydrogelswas studied by Fourier Transform Infrared Spectroscopy and their pore structurewas investigated by using Scanning Electron Microscope.