Surface Functionalization of Porous Polypropylene Membranes with Molecularly Imprinted Polymers by Photograft Copolymerization in Water

Abstract

In the presence of a template, desmetryn, commercial porous polypropylene membranes 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 polymerization conditions on membrane properties was studied by solute sorption analyses and membrane permeability measurements as well as electron spectroscopy for chemical analysis, FTIR spectroscopy, BET analysis, and scanning electron microscopy. It was found that molecularly imprinted polymer (MIP) membranes can be obtained which possess group affinity for the template and other triazine herbicides. Remarkably, the MIP membrane affinity for the template in buffer solution can be improved by the presence of salt during photograft copolymerization. This work presents the first successful example for molecular imprinting by in situ polymerization in water and on the surface of a commercially available synthetic polymer. The novel MIP membranes can be used in a fast preconcentration step, solid-phase extraction, by a simple microfiltration for the determination of herbicides in water. The possibility to introduce specific binding sites into porous membranes by surface imprinting polymerization without reducing their high permeabilities opens a general way to design new high-performance affinity membranes.

Protein-selective adsorbers by molecular imprinting via a novel two-step surface grafting method

“…[125] This method was later improved by Ulbricht and his coworkers by using -scission photoinitiation benzoin ether on the membrane surface, an imprinting effect could only be detected when this initiator had been coated to the surface, and not for the identical reaction mixture containing the dissolved benzoinether, therefore, the imprinted polymer layer was 42 controlled well on the membrane surface not in the bulk mixture. [82,126] Fukazawa and Ishihara developed a fibronectin imprinted polyethylene membrane via UV irradiation, the template protein at first form a complex with silica bead, then this protein-silica particle add to a mixture include poly(2-methacryloyloxyethyloxycarbonyl 4-phenylazido) with UVreactivity as scaffold polymer.…”

Poly(acrylic acid) surface grafted polypropylene films: Near surface and bulk mechanical response

“…Surface modification can be accomplished by increasing the polarity introducing special chemical functionalities like carboxylic groups, or by coating the surfaces with polar thin films, for example, poly(acrylic acid) (PAA). Surface grafting techniques including photo-initiated grafting [10][11][12][13][14], living radical grafting [15], ceric ion induced grafting [16], layer-by-layer ionic grafting [17] and plasma polymerization [18,19] have proven to be effective to graft poly-functional monomers or polymers onto PP surfaces. Among the methods to modify polymers, radical photo-grafting polymerisation appears as an attractive method to impart a variety of functional groups to a polymer [20,21].…”

Cellulose acetate-based molecularly imprinted polymeric membrane for separation of vanillin and o-vanillin

“…However, the practical application of MIPs is still under development (Haupt and Mosbach, 2000). Recently, MIP membranes prepared by photoinitiated surface modification of microfiltration membranes in the presence of template molecules have attracted much research interest due to the ability to change their diffusive permeability automatically by responding to the template molecules (Piletsky et al, 2000, Kochkodan et al, 2001). The MIP membranes have shown selective adsorption of target molecules (Takeda and Kobayashi, 2006), and the technique has also been applied to other research fields, which focus on separation of food (Trotta et al, 2002) and medicine (Yoshikawa et al, 2006).…”