Separation techniques are increasingly important processes for chemical industry and relate to the isolation of certain components of complex mixtures. Organic solvent nanofiltration, in particular, involves the separation of solvent molecules from larger molecules, aggregates, or metal complexes based on size selective permeation. Researchers from Imperial College (led by Prof. Andrew Livingstone) have developed new polymer nanomembranes based on polyacrylate networks, and have recently published their findings in Nature Materials.
The membranes were synthesised by interfacial polymerisation of multifunctional aromatic alcohols with multifunctional acyl chlorides (on a macroporous polyimide support) leading to highly crosslinked polymer networks a few hundreds of nanometers thick.
By using non-planar aromatic alcohol monomers they were able to significantly enhance the nanoporosity of the membranes due to inefficient packing of the polymer chains. This inventive step has led to exciting new nanomembranes which are able to rapidly separate small solvent molecules very efficiently.