Figure 5.

(a) CO₂ vs. CH₄ mixed-gas solubility coefficient of 6FDA-mPDA at 35 °C—solid lines were estimated via linear fitting of experimental data (the dotted curves delimit the confidence intervals of each linear interpolation); (b) data of CO₂/CH₄ mixed-gas solubility selectivity vs. CH₄ mixed-gas solubility coefficient of 6FDA-mPDA (CO₂/CH₄ mixed-gas solubility selectivity vs. CH₄ mixed-gas solubility coefficient mixed- (solid line) and pure-gas trends (dashed-line) are also shown for comparison). Mixed-gas solubility coefficient data from previous reports on PDMS [11], PIM-1 [20], TZ-PIM-1 [23], PTMSP [15], and PPO [18] are included in (a,b).