Preparation and Swelling Behaviour of Carboxymethylcellulose-g- Poly(sodium acrylate)/Kaolin Super Absorbent Hydrogel Composites

Abstract

In this paper, a novel biopolymer-based superabsorbent hydrogel composite based on carboxymethylcellulose (CMC) has been prepared via graft copolymerization of acrylic acid in the presence of kaolin powder using methylenebisacrylamide as a crosslinking agent and ammonium persulfate as an initiator. The synthetic variables i.e. acrylic acid, methylenebisacrylamide and ammonium persulfate concentration, as well as the kaolin amount affecting on water absorbency of the resulted superabsorbent composite were studied. Evidence of grafting and kaolin interaction was obtained by comparison of FTIR spectra of initial substrates and superabsorbent composite. The effect of various salt media and solutions with different pHs on the swelling of the super absorbent was also studied.