PROPERTIES OF CHELATING RESINS PREPARED BY ADDITION OF 1,4,8,11-TETRAAZACYCLOTETRADECANE-5,7-DIONE TO EPOXY GROUPS OF POLY(GLYCIDYL METHACRYLATE)S CROSS-LINKED WITH OLIGOETHYLENE GLYCOL DIMETHACRYLATES

In order to improve Cu(II) adsorption ability of chelating resins base d on a macrocyclic ligand and 1,4,8,11-tetraazacyclotetradecane-5,7-di one (L) bound to crosslinked copolymers, the resins were prepared by r eaction of L with poly(glycidyl methacrylate)s crosslinked with ethyle ne glycol dimethacrylate (1G), tetraethylene glycol dimethacrylate (4G ) or nonaethylene glycol dimethacrylate (9G). By systematically changi ng the amounts of each crosslinker (degree of crosslinking) and of iso butyl acetate (IBA) as diluent in the suspension polymerization of the monomers, precursory copolymers with various degrees of crosslinking as well as with different specific surface areas (SSAs) were prepared, and then L was introduced into them. Ligand contents, SSAs, and Cu(II ) adsorption abilities of the resulting resins were evaluated, and it was clarified that resins derived from precursors (prepared by using 4 G or 9G in the presence of 120-160 vol % of IBA) exhibit high capaciti es for Cu(II), whereas the capacities of resins crosslinked with 1G ar e not so high. Further detailed study on the uptake of metal ions usin g the resins RG4D(10)-140 and RG9D(10)-140 (derived from the precursor s prepared by using 10 mol % of the respective crosslinkers 4G and 9G in the presence of 140 vol % of IBA) showed that RG9D(10)-140 is much superior to RG4D(10)-140 in the column-mode adsorption of Cu(II). Thes e results indicate that not only the selection of the suitable crossli nker but also the use of a pertinent amount of the diluent are very im portant in improving the complexing abilities of the polymer-bound L. (C) 1996 John Wiley & Sons, Inc.