PEG‐Imbedded PEO Membrane Developed by a Novel Highly Efficient Strategy Toward Superior Gas Transport Performance

Low‐molecular‐weight poly(ethylene glycol) (PEG) is deliberately incorporated into synthesized swellable poly(ethylene oxide) (PEO) membranes via a facile post‐treatment strategy. The membranes exhibit both larger fractional free volume (FFV) and a higher content of CO₂‐philic building units, resulting in significant increments in both CO₂ permeability and CO₂/H₂ selectivity. The separation performance correlates nicely with the microstructure of the membranes. This study may provide useful insights in the formation and mass transport behavior of highly efficient polymeric membranes applicable to clean energy purification and CO₂ capture, and possibly bridge the material‐induced technology gap between academia and industry.