Spacer effect of novel bifunctional organophosphorus monomers in metal-imprinted polymers prepared by surface template polymerization

The interfacial activity and the molecular structure of functional monomers are critical factors that determine the success of synthesizing metal-imprinted polymers by surface template polymerization. From this point of view, first we prepared three distinct novel bifunctional organophosphorus monomers that are interspaced, in each case, by an alkyl spacer having a specific length. Each monomer carries two phosphonic acid groups and two aromatic groups in its molecular structures. Further, by using the synthesized bifunctional monomers, we prepared highly selective Zn(II)-imprinted polymers by the surface template polymerization initiated from a water-in-oil emulsion. To evaluate the template effect, we conducted diagnostic adsorption studies on Zn(II)-imprinted and unimprinted polymers with zinc ions. A high interfacial activity was found to be required for the functional monomers to create the predominant template effect. It became clear that Zn(II)-imprinted polymers having bifuctional monomers with 12-length alkyl chains (1,12-dodecanediol-O, O′-diphenyl phosphonic acid: DDDPA) yielded the best results. Moreover, analysis results of adsorption behavior supported a high-performance of the Zn(II)-imprinted polymers with DDDPA.