Owing to their high surface area, tunable pore sizes and high thermal stability polymers of intrinsic microporosity (PIMs) may find applications including gas capture, membrane-based separation and heterogeneous catalysis. PIMs are a class of glassy porous polymers that have rigid and contorted backbones, which pack inefficiently in the solid state resulting in high internal free volume. PIMs are characterized by high gas permeabilities but only low to moderate selectivities, which restrict their commercial use for important gas separation applications. In this study, we report an efficient approach to the synthesis of two rigid novel Tröger’s base (TB)-based-diamine monomers with sterically hindered di-ortho-substituted groups and explore their incorporation into novel 6FDA-based microporous polyimides via high temperature polycondensation. The two polyimides demonstrate excellent solubility, thermal and mechanical stability and relatively high BET surface areas. Pure-gas permeability coefficients of He, H2, N2, O2, CH4, and CO2 were measured at 35 °C and 2 bar for both fresh and 180 days aged films. For all tested gases, PIM-PI-TB-1 showed the highest permeabilities compare to all reported 6FDA-TB-based polyimides (i.e. CO2 permeability of 662 Barrer). Gas permeability dropped significantly coupled with a slight increase in the moderate selectivity after long-term aging of 180 days.

Synthesis, characterization and gas transport properties of Tröger’s Base-Based Polyimides of Intrinsic Microporosity (TB-PIM-PIs)

253rd National Meeting (2017)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.