Material Design Concepts and Gas Separation Mechanism of CO₂ Selective Polyether-Based Multiblock Copolymers

Aliphatic polyethers have been widely explored as membrane materials for the separation of CO₂ from other gases, e.g., N₂ , H₂ , CH_4, O₂ etc. The polymeric membranes having aliphatic polyether segments, especially poly(ethylene oxide) segments, allow faster permeation of CO₂ compared to the light gases due to the affinity of the polar ether oxygen and quadrupolar CO₂ . Rational macromolecular design is the key to control the permeation of gases through these membrane materials. In this regard, multiblock copolymers having short amorphous polyether segments have been extensively investigated. A large number of tailor made polymers have been reported to get the best combination of permeability and selectivity. Material design concepts and structure-property relationships of these membrane materials in terms of CO₂ separation performance are thoroughly discussed in this review.