Double logarithmic “Robeson”
plots of (a) H2/CO2, (b) H2/CH4 and (c) H2/N2 selectivity versus H2 permeability showing
Robeson’s 2008 upper bound29 (solid
line), and for H2/CH4 the 1991 upper bound30 (dashed line), with data for amine–PIM-1
as cast (⧫), ethanol-treated (◊), after aging for 18
months (▲) and methanol-treated after aging (Δ), compared
with literature data19 for PIM-1 as cast
(●) and methanol-treated (○), for thioamide–PIM-17 as cast (■) and ethanol-treated (□),
and for PIM-1 hydrolyzed under various conditions4 (×).