Fabrication of ether-oxygen-functionalized flexible thermally rearranged (TR) membranes with enhanced hydrogen separation
Year: 2025
Type: article
Abstract: An ideal gas separation membrane requires high permeability, selectivity, and mechanical flexibility. In this study, we developed functionalized polyimide precursors (coPI) by copolymerizing hydroxy-diamine, flexible diamine, and dianhydride to enhance these properties. 1H NMR and FTIR confirmed coPI synthesis, while tensile tests and DSC showed improved mechanical strength (51.84–72.74 N) and moderate glass transition temperatures (144–176 ℃) due to ether-oxygen segments and imide groups. SEM and SAXS revealed morphological changes in thermally rearranged (coTR) membranes. Gas permeation tests demonstrated that coTR-5, treated at 450 ℃, achieved an 18-fold increase in H₂ permeability (578.66 Barrer) with high H₂/CH₄ selectivity (46.15), surpassing the 2008 Robeson limit. The membrane also exhibited flexibility, plasticization resistance, and long-term stability. Molecular dynamics simulations indicated a high free volume (18.75 %), highlighting ether-oxygen diamine copolymerization as an effective strategy for designing advanced TR membranes.
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,060
OpenAlex ID: W4409798939