Chitosan modified MMT-poly(AMPS) nanocomposite hydrogel: Heating effect on swelling and rheological behavior



Vulnerability of hydrogels against thermal circumstances may be substantially eliminated via incorporating nanoclay to prepare nanocomposite hydrogels. In this research, chitosan-intercalated montmorillonite (ChitoMMT) was used as a bionanoclay to yield novel nanocomposite hydrogels based on 2-acrylamido-2-methylpropanesulfonic acid. The bionanoclay is suitable especially for preparing biomaterials used in biomedical, food, and pharmaceutical applications, unlike conventional commercial nanoclays (alkyl ammonium-intercalated MMT) which are not appropriate for bio-applications due to toxicity of the intercalant particularly where the clay content is high. Two different crosslinkers (i.e., methylene bisacrylamide, and polyethyleneglycol dimethacrylate) were employed to synthesize the nanocomposites. The variations in swelling, rheological and thermal properties of the hydrogels were essentially attributed to thermally induced crosslink cleavage/formation depending upon the crosslinker nature. The nanocomposites comprised superior thermal properties in comparison with the clay-free hydrogel counterpart. They can preserve substantially their swelling ability for longer heating periods. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010