High-performance Polymer Membranes with Multi-functional Amphiphilic Micelles for CO₂ Capture

Herein, we report a high performance polymer membrane with simultaneously large improvements in the CO₂ permeability and CO₂/N₂ selectivity. These improvements are obtained by incorporation of a multi-functional amphiphilic comb copolymer micelle, that is, poly(dimethylsiloxane)-g-poly(oxyethylene methacrylate) (PDMS-g-POEM), into a poly(amide-b-ethylene oxide) (Pebax) matrix. Both CO₂ and N₂ permeabilities continuously increased with PDMS-g-POEM content, whereas the CO₂/N₂ selectivity increased up to 40 wt % of PDMS-g-POEM, which enabled the maximum performance to approach the upper bound limit (2008). The membranes with PDMS-g-POEM exhibited greater CO₂ permeability and CO₂/N₂ selectivity than those with a zeolitic imidazolate framework (ZIF-8), a well-known expensive inorganic filler, indicating the effectiveness of PDMS-g-POEM micelles for CO₂ capture.