Abstract: Bentonite/polyacrylic acid composite superabsorbent was prepared via microwave irradiation. The structure and morphology were analyzed by FTIR, XRD, and SEM. The effect of the preparation conditions on absorption of water was investigated. The optimal conditions were that the weight ratio of bentonite to AA was 8/1, microwave power was 720 W, neutralization degree was 80 %, the mass fraction of initiator and crosslinker were respectively 0.02 % and 0.8 %. XRD showed that the distance between the silicate layers of bentonite was increased, the monomer was intercalated into the bentonite layer and formed a crosslinked structure. SEM showed that porous products were easily obtained through microwave irradiation. The characterization of synthesized highabsorbent resin showed that the maximum water absorbency was 1312 g/g in distilled water and 320 g/g in 0.9 % NaCl, respectively. The water absorption rate was high, and the swelling processes of the composites agreed with firstorder kinetics, and the retain water of the composites was temperature dependent.

Key words: bentonite, acrylic acid, composite, superabsorbent resin, microwave irradiation