Characteristic and kalium-releasing performance of fly ash superabsorbent polymer composite material

Fly ash/polyacrylic acid-acrylamide(PAA) superabsorbent polymer composite material was firstly prepared by means of solution polymerization.The composite material can absorb distilled water,tap water and 0.9% NaCl solution.Absorbing rate is higher than the requirement of the National 863 Program and the cost is less than that by pure macromolecule superabsorbent polymer.K+ releasing rate is 8.70% when fly ash is mixed into superabsorbent polymer so that the composite material has the performance of release kalium.The mechanism of release kalium is that K_2O in the fly ash has neutralization reaction with acrylic acid.X-ray diffraction shows that the main crystal structure of fly ash in composite material is not changed.The structure and composition of this material were studied by infrared spectrum analysis.Scan electron microscope illuminates that the fly ash is compounded well with macromolecule polymer and there is no evident split between fly ash and macromolecule polymer.