A rigid flow control device includes a porous rigid body having an outer surface and an inner surface. The body defines a flow path and is formed from a material operatively arranged with a surface energy less than that of the fluid for passively impeding an undesirable component of the fluid more than a desirable component of the fluid.

A porous ultra-thin polymer film has a film thickness of 10 nm-1000 nm. A method of producing the porous ultra-thin polymer film includes dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

A method of manufacturing a porous fluorine-containing polymer membrane is provided, which includes mixing a fluorine-containing polymer, a pore creating agent, and a solvent to form a mixture; forming a membrane of the mixture, and removing the pore creating agent and the solvent in the membrane to form the porous fluorine-containing polymer film. The pore creating agent has a chemical formula of ##STR00001##
wherein R.sup.1 is a C.sub.1-8 alkyl group, a C.sub.2-8 alkenyl group, a C.sub.2-8 alkynyl group, or a C.sub.6-12 aromatic group, and A.sup.? is hydrogen sulfite ion, dihydrogen phosphate ion, nitrate ion, halogen ion, or a combination thereof. The solvent has a chemical formula of ##STR00002##

The objective of the present invention is to provide a porous ultra-thin polymer film, and a method for producing said porous ultra-thin polymer film. The present invention provides a porous ultra-thin polymer film with a film thickness of 10 nm-1000 nm. In addition, the present invention provides a method for producing a porous ultra-thin polymer film, comprising the steps of: dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

Provided are a polyethylene microporous membrane, a method for manufacturing the same, and a separator including the microporous membrane. According to an embodiment of the present disclosure, a microporous membrane is provided which includes a polyethylene having a weight average molecular weight of 1?10.sup.5 g/mol to 10?10.sup.5 g/mol, and has a thickness of 3 ?m to 20 ?m, a puncture strength of 0.25 N/?m or more, a gas permeability of 1.5?10.sup.?5 Darcy or more, a shrinkage rate in the transverse direction of 10% or less as measured after being allowed to stand at 131? C. for 1 hour, a tensile strength in the machine direction of 1500 kg/cm.sup.2 or more, a tensile strength in the transverse direction of 2000 kg/cm.sup.2 or more, and a ratio between the tensile strength in the machine direction and the tensile strength in the transverse direction of 0.5 to 0.7.

Provided are a polypropylene microporous membrane, a method for manufacturing the same, and a separator including the microporous membrane. According to an embodiment, a polypropylene microporous membrane including a polypropylene having a viscosity average molecular weight of 1?10.sup.6 g/mol to 3?10.sup.6 g/mol, a thickness of 3 ?m to 30 ?m, and exhibits a puncture strength of 0.20 N/?m or more, a gas permeability of 1.0?10.sup.?5 Darcy or more, and a shrinkage rate in the transverse direction of 20% or less as measured after being allowed to stand at 150? C. for 1 hour, is provided.

Provided is a porous anion exchange membrane including a porous polymer support; and an anion-permselective material supported in the porous polymer support, in which the porous anion exchange membrane has a micro-nano composite pore structure including microscale pores and nanoscale pores.

A hollow fiber membrane and a method of preparing the same. The hollow fiber membrane has an inner surface and an outer surface, wherein the inner surface has a zebra-stripe pattern in which a dense portion and a porous portion are alternately formed in a longitudinal direction of the hollow fiber membrane.

Provided is a novel continuous single-step method of manufacturing a multilayer sorbent polymeric membrane having superior productivity, properties and performance. At least one layer of the polymeric membrane comprises sorbent materials and a plurality of interconnecting pores. The method includes: (a) coextruding layer-forming compositions to form a multilayer coextrudate; (b) casting the coextrudate into a film; (c) extracting the film with an extractant; and (d) removing the extractant from the extracted film to form the multilayer sorbent polymeric membrane. The sorbent membrane of this disclosure can find a wide range of applications for use in filtration, separation and purification of gases and fluids, CO.sub.2 and volatile capture, structural support, vehicle emission control, energy harvesting and storage, electrolyte batteries. device, protection, permeation, packaging, printing, and etc.

There is provided a method for preparing microporous hollow fiber membranes comprising melt-extruding a polymer-salt blend followed by salt leaching. Microporous hollow fiber membranes are also disclosed.