Unexpected barrier properties of structurally matched and unmatched polyelectrolyte multilayers

Structurally unmatched hyperthin (14 nm) polyelectrolyte multi-layers (PEMs) formed on poly[1-(trimethylsilyl)-1-propyne] supports exhibit exceptionally high CO2/N2 permeation selectivities, ranging from 100 to 150. Structurally matched PEMs show similar selectivities with significantly higher permeances.