GAS PERMEATION THROUGH GLASSY POLYMER MEMBRANES WITH HIGH GLASS-TRANSITION TEMPERATURE

The sorption equilibria and permeation rates for carbon dioxide in such glassy polymer membranes with high glass-transition temperature as polyimide, polyetherimide, polysulfone and polyethersulfone membranes, were measured. The sorption isotherms for these systems can be described well by the dual-mode sorption model, whereas the pressure dependences of the mean permeability coefficients are simulated better by a modified dual-mode mobility model than the conventional dual-mode mobility model in which the Henry's law and Langmuir populations execute four kinds of diffusive movement.