Table 1 Non-litographic methods of isoporous membrane preparation.

Track-etching

PET, PC

0.2–2

Tracking by high energy particles in a nuclear reactor or accelerators followed by etching in caustic medium; regular size pores; pore merging might occur, low pore density; no solvent required; commercialized in discs with 47 mm (or lower) diameter

^1,2

Anopore/Anodisc

Anodic Aluminum Oxide (AAO)

0.02–0.2

Anodization of aluminum by an electrochemical process; commercialized in discs with 47 mm (or lower) diameter; inorganic; highly brittle

²⁷

Block copolymer self-assembly, followed by selective etching

Copolymers with polylactide blocks

0.02–0.06

Self-assembly in selective solvent, followed by long etching of the polylactide blocks in NaOH; lab-scale demonstration

²⁸

Block copolymer SNIPS

Block copolymers

0.002–0.1

Self-assembly in selective solvents and macrophase separation in water; asymmetric; under consideration for commercialization (start-up Terapore), mostly with polystyrene and vinyl pyridine blocks;

⁴

Breath figures

Block copolymers/ homopolymers

1–5

Water droplets condensation on spread polymer solution (preferentially apolar solvents); highly dependent on humidity level and other conditions; lab scale demonstration

^5,6,7

Incorporation of sacrificial particles

Crosslinked acrylate

0.03–0.3

Float-cast microsieves prepared by photocrosslinked acylate monomers in solution with silica microspheres, followed by etching with hydrofluoric acid; lab scale demonstration

⁸

Molecular templating/supramolecular assembly

Epoxy/ linoleic acid

0.001–0.002

Crosslinking of systems with assembled discoid templates in solution, followed by etching; lab scale demonstration

⁹