Block Copolymer Membranes for Aqueous Solution Applications

Abstract

Block copolymers are known for their intricate morphology. We review the state of the art of block copolymer membranes and discuss perspectives in this field. The main focus is on pore morphology tuning with a short introduction on non-porous membranes. The two main strategies for pore formation in block copolymer membranes are (i) film casting and selective block sacrifice and (ii) self-assembly and non-solvent induced phase separation (SNIPS). Different fundamental aspects involved in the manufacture of block copolymer membranes are considered, including factors affecting the equilibrium morphology in solid films, self-assembly of copolymer in solutions and macrophase separation by solvent-non-solvent exchange. Different mechanisms are proposed for different depths of the SNIPS membrane. Block copolymer membranes can be prepared with much narrower pore size distribution than homopolymer membranes. Open questions and indications of what we consider the next development steps are finally discussed. They include the synthesis and application of new copolymers and specific functionalization, adding characteristics to respond to stimuli and chemical environment, polymerization-induced phase separation, and the manufacture of organic-inorganic hybrids.3

Artificial membranes with selective nanochannels for protein transport

“…Membrane fabrication with vertically aligned channels from this terpolymer is challenging. Previous works of our group 12,47,48 and others demonstrated the pore formation in membranes with additives in solution, which promote lamellar or hexagonal spherical morphologies by controlled hydrogen bond. The equilibrium morphology of the PS 40k --b--PHS 27.3k --b--PS 40k terpolymer has interesting domains containing O--H functional groups.…”

Photoresponsive nanostructured membranes

“…The manufacture of highly ordered nanoporous membranes has been previously demonstrated by using the following block copolymers: PS--b--P4VP, 19 PS--b--PEO, 32 and PI--b--PS--b--P4VP. 20 The pore formation in block copolymer membranes has been recently reviewed 33 and discussed in detail. Here for the first time PS--b--PAnMMA--b--PMMA triblock copolymer was used for membrane preparation.…”

Porous Polymer Membranes by Hard Templating – A Review

“…The adaption of pore sizes within one specific polymer is an efficient process. [91][92][93][94][95][96][97] However, changing the polymeric systems requires a novel synthesis of the entire polymer. The synthesis and release is a multistep process, thus the production of large scales of membrane is demanding (e.g., solvent use).…”