Nano-structured magneto-responsive membranes from block copolymers and iron oxide nanoparticles

Mixed matrix membranes (MMMs) provide an exciting alternative to traditional membranes due to their favorable properties from both building blocks which are essential for certain separation applications. Block copolymer directed synthesis of MMMs is an innovative approach for the preparation of porous materials. In the current work the syntheses of mixed matrix membranes from a PMAA-b-PMMA block copolymer and functionalized iron oxide magnetic nanoparticles are demonstrated. The block copolymers were synthesized using a RAFT polymerization technique, along with three different types of magnetic nanoparticles with various surface properties. The thin film membranes were prepared by mixing different ratios of diblock copolymer in THF and iron oxide nanoparticles in water followed by tape casting or spin coating. The particles and the membranes were characterized using TEM, DLS, and SEM. The permeation behavior of the membranes was assessed using filtration tests in the presence and absence of a magnetic field.