1Polymer Research Laboratory, Faculty of Chemistry, sharif University of Technology, P.O. Box 11365-9516 Tehran, I.R. IRAN
2Department of Chemistry, Payame Noor University, Gazvin Branch, P.O. Box 878 Qazvin, I.R. IRAN
A hydrophilic macromolecular network is prepared by performing graft copolymerization of poly (sodium acrylate) chains onto salep and silica gel. The reaction parameters affecting the water absorbency of the superabsorbent composite were optimized using Taguchi method. FT-IR spectroscopy and Thermo Gravimetric Analysis (TGA) were used for confirming the structure of the final product and morphology of the synthesized superabsorbent composite was examined by SEM.The swelling behavior of optimum superabsorbent composite was measured in various swelling media. In addition, swelling kinetics and on-off switching behavior were investigated. In order to evaluate the controlled release potential of the matrix, it was loaded with KNO3 and NH4NO3 as a model agrochemical and the release kinetics was studied.
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