Adsorption of Metal Ions to Surface-Template Resins Prepared with Amphiphilic Styrene Monomers Bearing Amino Carboxylic Acid

Article abstract of DOI:10.1246/bcsj.71.789

Monomer-type functional surfactants, 2-(p-vinylbenzylamino)alkanoic acid (R_nAc) and N,N-dialkyl derivatives (RR_nNAc), have been used as both a ligand and an emulsifier for the preparation of surface-template resins. The surfactants adsorbed at the toluene-water interface and emulsified divinylbenzene-styrene in a Cu²⁺ or Zn²⁺ solution. Emulsion polymerization using a K₂S₂O₈ initiator (80 °C) or by irradiation with γ-rays gave fine particles of 200-800 nm in diameter. Metal-imprinted resins prepared with R_nNAc and RR_nNAc showed a high adsorptive capacity for the metal ion (surface-template effect). Cu-imprinted resins prepared with R₈NAc were 2.69-times as effective for Cu²⁺ in competitive sorption from a Cu²⁺-Zn²⁺ mixture and Zn-imprinted resins were 1.84-times as effective for Zn²⁺, compared with unimprinted resins. Because of the great emulsifying power, metal-imprinted resins prepared with R₈NAc showed the most metal-selective adsorption and the largest capacity among resins prepared with R_nNAc and RR_nNAc.