Enhancing the Gas Permeability of Troger's Base Derived Polyimides of Intrinsic Microporosity

A series of four novel Troger's.base (TB) derived polyimides of intrinsic microporosity (PIM-TB-PI) is reported. The TB diamine monomer (4MTBDA) possesses four methyl groups, in order to restrict rotation about the C-N imide bonds in the resulting polymers. The polymers possess apparent BET (Brunauer, Emmett, and Teller) surface areas between 584 and 739 m(2) g(-1), complete solubility in chloroform, excellent molecular mass, high inherent viscosity and good film-forming properties. Gas permeability measurements demonstrate enhanced perform-ance over previously reported polyimide-based Troger's base (TB) polymers confirming the benefit of the additional Methyl groups within the TB diamine monomer. Notably, a polyimide derived from 4MTBDA and pyromellitic anhydride (PI\WA) demonstrates gas permeability data above the 2008 upper bounds for important gas pairs such as O-2/N-2, H-2/N-2, and H-2/CH4.