ABSTRACT
In the last two decades, various engineered glassy polymers have been developed with both experimental and commercial values. These materials combine high selectivities with acceptable permeability coefcients and, therefore, are suitable for the preparation of gas separation membranes (Barsema et al. 2003). The glassy state offers a more structured sieving matrix than a rubbery state, as well as higher load-bearing properties, allowing high pressure drop across the membrane. Thus, the separation of common gas pairs is accomplished by diffusion control or sizeselective sieving mechanisms (Robeson 1999).
