| Superabsorbents can absorb a large amount of water compared with general water absorbing materials in which the absorbed water is hardly removable even under some pressure. Because of their excellent characteristics, superabsorbents are widely used in health, agriculture and horticulture applications.Based on the influencing factors, such as type of structural layer, interlayer charge, interlayer distance, cation exchange capability, surface area and ratio of swelling, kaolinite, sercite and bentonite are choosed as the mineral fillers to synthesize the superabsorbent composite. It is significant for reducing the product cost and improving the comprehensive property of the superabsorbent composite.Using ammonium eerie nitrate and N,N'-methylene-bis-acrylamide as an initiator and crosslink agent respectively, a superabsorbent composite is prepared by graft polymerization of acrylamide on starch at the presence of clay suspension, followed by hydrolyzing, washing, drying, grounding and filtering. The water absorbency and salt water absorbency of the superabsorbent composite is 3010 g.g-1 and 138 g.g-1 respectively. The composite has excellent performance of water retaining, that the adsorbed water of 85% is retained after being dried 10 days at the room temperature, and the adsorbed water of 45% is retained after being dried 24 hours at 60The factors influencing on water absorbency for the superabsorbent composite such as the kinds and concentration of starch, clay, crosslinker, initiator, the external salt solution and hydrolysis degree are investigated in this paper. The suitable preparing condition of the composite has been set down by a series of experiments.The clay/poly-acrylamid superabsorbent composite is characterized by Infrared (IR), thermogravimetry, analysis (TGA), differential scanning, calorimetry (DSC) and X-ray diffraction analysis (XRD). It is significant of the preparation of materials and device of property for superabsorbent composite.
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