Interfacial Polymerization of Reactive Block Polymers for the Preparation of Composite Ultrafiltration Membranes

Abstract

Interfacial polymerization of an acid chloride-containing block polymer and a multivalent amine in the presence of a macroporous support was explored as a means to generate a nanoporous thin film composite (TFC) membrane potentially useful for ultrafiltration. When polylactide-<i>b</i>-poly­(styrene-<i>co</i>-vinylbenzoyl chloride) (PLA-<i>b</i>-P­(S-<i>co</i>-VBC)) in an organic phase and <i>m</i>-phenylenediamine (MPD) in an aqueous phase were used as the reactive block polymer and the amine, respectively, a block polymer thin film was successfully formed on a polysulfone support. This nanostructured film could be converted into a nanoporous layer by subsequent PLA etching under mild basic conditions. While most organic solvents used to dissolve PLA-<i>b</i>-P­(S-<i>co</i>-VBC) damaged the support and decreased permeability of the resulting membrane, use of a mixture of methyl isobutyl ketone and acetonitrile produced a TFC membrane with high permeability