Extended Data Fig. 3: Fabrication and photograph of PIM membranes.
From: Hydrophilic microporous membranes for selective ion separation and flow-battery energy storage
a, Thick symmetric membranes were fabricated by casting a polymer solution onto a clean glass plate using a doctor blade, followed by slow evaporation of solvent over two days. b, Thin films were fabricated by spin coating a dilute polymer solution onto a substrate. Thin film composite membranes were obtained by using a porous support as the substrate, while a glass plate was used to make freestanding thin films. c, Freestanding thick and thin films were peeled off the glass plates by floating onto water surface. d, Photo of a freestanding 300-nm-thick PIM-EA-TB film supported on a polydimethylsiloxane (PDMS) O-ring for ion dialysis test. e-f, Photos of AO-PIM-1 (e) and PIM-EA-TB (f) membranes in the dry (left) and fully hydrated (right) states. No significant swelling was observed after immersing the dry PIM membranes in DI water for 24 hours. The swelling ratios of AO-PIM-1 and PIM-EA-TB membranes in linear dimensions were 6.9 ± 1.0%, and 11.7 ± 0.3%, respectively. The swelling measurements were based on at least three membranes. g, Photo of an AO-PIM-1 membrane. The manufacturing of membranes was scaled up to about 20 cm × 20 cm.
