Synthesis of chelating resins based on poly(styrene-co-divinylbenzene) and poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate)

Abstract

A number of poly(styrene-divinylbenzene) resins with gel-type and macroporous morphologies have been synthesised by suspension polymerization. These have been chloromethylated using a procedure which generates chloromethyl methyl ether in situ. The merits of this route are discussed. A similar gel-type resin has also been made directly using vinyl benzyl chloride as the major comonomer. Two amino-aromatic and four amino-aliphatic chelating species have been attached to these resins to yield ligand loadings of ∼ 30–40% in the case of the macroporous supports and ∼ 65–85% in the case of the gel-types. No distinction was apparent between the styrene and the vinyl benzyl chloride-based resins. Typical examples of a gel-type and a macroporous species have also been functionalised with a spacer arm, and two amino-aromatic ligands attached via this. In each case the loading achieved was much lower than when the same ligands were attached directly, confirming the problems associated with multistep reactions on resins. A macroporous glycidyl methacrylate-based resin has also been prepared with a particle size of ∼300–800 μm. Ring opening of the pendant epoxy group with primary amine has allowed the facile introduction of all the ligands mentioned above, along with four nitrogen ∼ 20–50%, the original epoxy content being ∼ 60% (of pendant groups). These range ∼ 20–50%, the original epoxy content being ∼ 60% (of pendant groups). These results confirm the versatility of glycidyl methacrylate resins, and considerably increase the variety of ligands which have been attached.