LAUSR

Abstract A sodium humated (SH) modified superabsorbent resin (SAR), which had good water absorbency and slow-release fertilizer properties has been successfully prepared by inverse suspension polymerization. The structure and morphology of the as-prepared SAR was characterized by Fourier Transform Infrared Spectroscopy (FTIR), Optical Microscope (OM) and Thermogravimetric Analysis (TGA). The effect of initiator content, crosslinker content, oil-water ratio and temperature on the water absorbency of the SAR was investigated. Under optimum conditions, the water absorbency reached 1097 g/g and 103 g/g in deionized water and 0.9 wt% NaCl solution, respectively. The moisture resistance capacity of SAR with SH increased to 2%. What’s more, the SH modified SAR also had better water absorbency in different cation solutions. The slow-release test showed a two-stage release characteristic of SAR that fast rate in first 12 days (carbon content reached 0.218 mg / 5 ml) and slow rate from 12 to 30 days (carbon content reached 0.242 mg / 5 ml). The degradation performance test showed that degradation rate of the SAR in soil could reach 31.9% after 100 days.