Preparation Of Thermosensitivity Polymer Adsorbent And Research On Dynamic Shedding Of Chelate

Heavy metal ions are hard to transfer in the environment and will cause damageto natural environment and organisms. Compared with traditional processing methods,polymer chelating agent has better chelating ability, it can form a stable chelate withheavy metal ions in sewage samples.In this paper, we reported the synthesis of the linear random PNIPAM-co-MA viaradical polymerization using azo-initiator, then hydrazined for PNIPAM-co-AH.2,4-dinitrobenzene formaldehyde was reacted with PNIPAM-co-AH to obtainacylhydrazone. The properties of products of each stage were characterized by FTIRand NMR. The results indicated that the products were the target products.The polymer adsorbent was used for chelate copper ion and chromium ion. Weused AAS to quantify the concentrations of copper ion and chromium ion before andafter chelation reactions between polymer adsorbent and heavy metal ions. The resultsthat concentration of copper ion was under the test range of AAS instrument after fiveadsorption reactions(μg/L), and concentration of chromium ion was under the testrange after two adsorption reactions, both ions’ concentrations of emission hasreached the national standard.Heavy metal ion chelates were used for dynamic peeling experiment. We usedGPC to characterize the dynamic fall off reversible reaction of chelation unit. Theresults indicated that acylhydrazone side chain could fall out from the main chain ofthe polymer through changing pH, so the chelating agent could be reused.