Surface functionalization of porous polypropylene membranes with molecularly imprinted polymers by photograft copolymerization in water

In the presence of a template, desmetryn, commercial porous polypropylene m embranes were photografted, using benzophenone as photoinitiator, with the functional monomer 2-acrylamido-2-methylpropanesulfonic acid and the cross- linker N,N'-methylenebis(acrylamide) in water. The influence of the polymer ization conditions on membrane properties was studied by solute sorption an alyses and membrane permeability measurements as well as electron spectrosc opy for chemical analysis, FTIR spectroscopy, BET analysis, and scanning el ectron microscopy. It was found that molecularly imprinted polymer (MIP) me mbranes can be obtained which possess group affinity for the template and o ther triazine herbicides. Remarkably, the MIP membrane affinity for the tem plate in buffer solution can be improved by the presence of salt during pho tograft copolymerization. This work presents the first successful example f or molecular imprinting by in situ polymerization in water and on the surfa ce of a commercially available synthetic polymer. The novel MIP membranes c an be used in a fast preconcentration step, solid-phase extraction, by a si mple microfiltration for the determination of herbicides in water. The poss ibility to introduce specific binding sites into porous membranes by surfac e imprinting polymerization without reducing their high permeabilities open s a general way to design new high-performance affinity membranes.