Thiol functionalized polymer submicron particles prepared by soap‐free emulsion polymerization and their adsorption of lead ions in water

Abstract

AbstractOxidization, thiol‐ene click addition, and inhibition of thiols make it hard to prepare thiol‐containing particles from free radical polymerization. Using methyl methacrylate (MMA) and a newly synthesized polymerizable 2‐(((2‐[pyridin‐2‐yldisulfanyl]ethoxy)carbonyl)amino) ethyl acrylate (PDSECAE) as monomers, the P(MMA‐co‐PDSECAE) submicron particles (SPs) were first prepared by soap‐free emulsion polymerization, in which the thiol was protected in the form of pyridyl disulfide group from side reactions. The thiol functionalized P(MMA‐co‐PDSECAE)‐SH SPs were obtained by post‐treating the SPs with dithiothreitol (DTT), and then used to adsorb Pb2+ in water. Results showed that in the preparation of these SPs, the initiator type, the initial pH and the PDSECAE dosage played an important role in the stability of polymerization and the resulted emulsions, and the colloid properties as well as the content of thiol groups of the P(MMA‐co‐PDSECAE)‐SH SPs. The P(MMA‐co‐PDSECAE)‐SH SPs had nearly 10 times greater Pb2+ adsorption capacity than the corresponding PMMA SPs or P(MMA‐co‐PDSECAE) SPs under optimized experimental conditions, and the adsorption capacity of Pb2+ increased with PDSECAE dosage and the DTT reduction time. Due to the relatively large specific surface area and easy preparation process, the P(MMA‐co‐PDSECAE)‐SH SPs have potential application value in the adsorption of heavy metal ions.