A simple self-regulating permeability and selectivity of poly (arylene ether ketone) with amino groups for gas separation membrane

Poly (arylene ether ketone) containing different content of the amino groups (Am-PAEK) polymer membranes were prepared by nucleophilic polycondensation used as gas separation membranes. Am-PAEK was synthesized successfully confirmed by Fourier Transform Infrared (FT-IR). The glass transition temperature (T_g) of Am-PAEK membranes enhanced from 164.83 °C to 192.83 °C, and the XRD results showed that the crystallinity of the Am-PAEK membranes increased as the amino groups content increased. The tensile strength and young’s modulus of the Am-PAEK-10% achieved 44.10 MPa and 2053 MPa, respectively. All of the Am-PAEK membranes exhibited excellent thermal performance. The gas separation capability testing showed that the Am-PAEK-10% membrane showed higher pure gas permeability [P(CO₂) = 12.38] as well as ideal permselectivity [α(CO₂/CH₄) = 21.34], the separation performance was closest the Robeson upper bound. It was due to that acid–base and hydrogen bond interactions between the amino groups and carbon dioxide exit in the membranes. Thus, the strategy of precise regulated the content of amino groups of Am-PAEK showed a prospective approach for high performance gas separation membranes.