Poly (amide-6-b-ethylene oxide) multilayer composite membrane for carbon dioxide separation

► Multilayer PEI/PDMS/PEBA/PDMS composite membrane is prepared by dip-coating method. ► For nonpolar gases, the gas permeance decreases with the increasing molecule size. ► For polar gases, the gas permeance increases with the increasing molecule size. ► The temperature dependence of gas permeance shows two different linear relationships. ► CO2 has low value of Ep, which decreases with the increasing pressure.