Syntheses of thiacrown ethers polymers and their application for heavy metal ion adsorbents

6-(4'-Vinylbenzyloxy)-1,4,8,11-tetrathiacyclotetradecane (S14S4) and 9-(4'-vinylbenzyloxy)-1,4,7,14,17-hexathiacycloeicosane (S20S6) were synthesized as thiacrown ether monomers by using a high dilution cyclization method. The thiacrown ether monomers were polymerized and copolymerized with styrene (St) and N-vinylpyrrolidone (NVP) by radical polymerization. Their affinity for the solvent was easily controlled by choosing the comonomer used. The thiacrown ether polymer ligands had binding selectivity for Ag(I) and Hg(II) ions like as a polymer ligand having acyclic polythioether units. The binding ability, however, was not affected by the shape of the thioether (either a cyclic ether or an acyclic ether) and by the copolymer composition. They can be used as an adsorbent under acidic condition and can reused repeatedly.