Postmodification of PS-b-P4VP Diblock Copolymer Membranes by ARGET ATRP
AbstractThe surfaces of polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymer membranes were modified in order to obtain polymer brushes by using surface-initiated Activators Regenerated by Electron Transfer Atom Transfer Radical Polymerization (ARGET ATRP) . Isoporous membranes were prepared by the combination of self-assembly of PS-b-P4VP diblock copolymers and the nonsolvent induced phase separation process, also known as “phase inversion”. In order to allow further functionalization the membranes were modified with an ATRP initiator, 2-bromoisobutyryl bromide (BIBB). Therefore, the mussel-inspired poly(dopamine) coating was used to attach BIBB on the membranes surface. In the next step the coated membranes were post-modified by using surface-initiated ARGET ATRP with the hydrophilic monomer 2-hydroxyethyl methacrylate (HEMA). The surface-initiated ARGET ATRP reaction was carried out under different reaction times and environments. PHEMA could successfully incorporate on the membrane surface as confirmed by attenuated total relection Fourier Transform infrared spectroscopy (ATR-FTIR), 1H-nuclear magnetic resonance spectroscopy (1H-NMR), scanning electron microscopy (SEM), and contact angle measurements, respectively. Furthermore stability tests against heat and solvents were performed and water flux was measured for raw and modified membranes.