State-of-the-art poly aryl sulfone (PAS)-based membranes for gas separation: A review on molecular design and structural engineering

Poly aryl sulfone (PAS) polymers are important as a commercial engineering class of polymers due to their superb physicochemical properties, extensively used for fabricating gas separation membranes, commercially in the H2/ NH3 separation and nitrogen production. However, there are still some challenging problems for PASs-based membranes: trade-off between gas permeability and permselectivity and long-term stability because of some limitations such as plasticization and physical aging. The present review aims to cover the recent development of PASs-based gas separation membranes and give the best insights into molecular architecture and advanced chemical modification methods applied to preserve/overcome the aforementioned problems. For this purpose, creating new structures is discussed in detail including molecular design and functionalization of PASs (tailoring pure PASs and design of copolymers), cross-linking, and grafting. Finally, a concise conclusion and research perspective are outlined, hoping to provide guidelines for the future of PASs-based gas separation membranes to meet the industrial requirement.