Permselectivity of Gases of Novel Polyimide Membranes Having Bulky Side Chain

摘要

There have been many papers published concerning the sorption, diffusion and permeation of not only rubbery polymers but also glassy polymers as reviewed by Stern [1]. Also, Robeson summarized the relationship of the gas permeability (P) and the ideal separation factor, or the gas selectivity (PA/PB) for a larger number of experiments and presented values in which the log-log plots of the selectivity versus the permeability coefficient (PA) have an "upper bound" [2]. The selectivities of many of the glassy poolymers are on the upper bound or very close to the upper bound. Polyimides have been synthesized from a tetracarboxylic dianhydride with a diamine by condensation olymerization. Therefore, many kinds of the polyimides can be synthesized by choosing a combination of the acid component and the diamine component. The structure/permeability relationships of these polyimides have been extensively reviewed [1]. The gas permeability and the selectivity of polyimides, however, containign the bulky moiety in the side chains of the polymers were not reported except for report of NEDO.