Disclosed are fouling resistant filtration membranes comprising a polymeric thin-film membrane comprising a surface. Also disclosed are methods of modifying thin-film filtration membranes, thereby improving, for example, the anti-fouling properties of the membranes. Also disclosed are methods of purifying water using the disclosed membranes. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present invention.

A composite membrane for selectively separating (e.g., pervaporating) a first fluid (e.g., first liquid such as a high octane compound) from a mixture comprising the first fluid (e.g., first liquid such as a high octane compound) and a second fluid (e.g., second liquid such as gasoline). The composite membrane includes a porous substrate comprising opposite first and second major surfaces, and a plurality of pores. A pore-filling polymer is disposed in at least some of the pores so as to form a layer having a thickness within the porous substrate. The composite membrane further includes at least one of: (a) an ionic liquid mixed with the pore-filling polymer; or (b) an amorphous fluorochemical film disposed on the composite membrane.

A polymer film comprising anionic groups and 0.008 to 25 mg/g of each of components (a) and (b): (a) a crosslinking agent which is free from fluoro groups and comprises a group of Formula (I); and (b) a non-ionic crosslinking agent; Formula (I) wherein M.sup.+ is a cation and * indicates the attachment points to other elements of the crosslinking agent.

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The present disclosure provides an acryloyloxy-terminated polydimethylsiloxane (AC-PDMS)-based thin-film composite (TFC) membrane, and a preparation method and use thereof. In the preparation method, a simple ultraviolet (UV)-induced monomer polymerization strategy based on high UV reactivity among acryloyloxy groups is adopted to prepare the AC-PDMS-based TFC membrane. The high UV reactivity among AC-PDMS monomers can induce the rapid curing of a casting solution to enable the formation of an ultra-thin selective layer and the inhibition of pore penetration for a substrate. By optimizing a UV wavelength, an irradiation time, and a polymer concentration, the prepared AC-PDMS-based TFC membrane has a CO.sub.2 penetration rate of 9,635 GPU and a CO.sub.2/N.sub.2 selectivity of 11.5. The UV-induced monomer polymerization strategy based on material properties provides a novel efficient strategy for preparing an ultra-thin PDMS-based membrane, which can be used for molecular separation.

This invention discloses a membrane composition, a method of making, and applications for a new type of high selectivity, high plasticization-resistant and solvent-resistant, both chemically and UV cross-linked polyimide membranes. Gas permeation tests on these membranes demonstrated that they not only showed high selectivities, but also showed extremely high CO.sub.2 plasticization resistance under CO.sub.2 pressure up to 4923 kPa (700 psig). This new type of high selectivity, high plasticization-resistant and solvent-resistant, both chemically and UV cross-linked polyimide membranes can be used for a wide range of gas separations such as separations of H.sub.2/CH.sub.4, He/CH.sub.4, CO.sub.2/CH.sub.4, CO.sub.2/N.sub.2, olefin/paraffin separations (e.g. propylene/propane separation), O.sub.2/N.sub.2, iso/normal paraffins, polar molecules such as H.sub.2O, H.sub.2S, and NH.sub.3 mixtures with CH.sub.4, N.sub.2, H.sub.2, and other light gases separations. The membranes can also be used for liquid separations such as in the removal of organic compounds from water.

The composite anion exchange membrane includes: a surface layer on a single surface or both surfaces of an anion exchange membrane substrate, in which the above-described surface layer contains a copolymer of a monomer A which is a water-soluble polyfunctional monomer and a monomer B which is a cationic monomer, an anion exchange capacity of the above-described surface layer is 0.05 meq/cm.sup.3 to 0.50 meq/cm.sup.3, and an anion exchange capacity of the above-described anion exchange membrane substrate is 1.0 meq/cm.sup.3 to 5.0 meq/cm.sup.3.

An article that can be used for biomaterial capture comprises (a) a porous substrate; and (b) borne on the porous substrate, a polymer comprising interpolymerized units of at least one monomer consisting of (1) at least one monovalent ethylenically unsaturated group, (2) at least one monovalent ligand functional group selected from acidic groups, basic groups other than guanidino, and salts thereof, and (3) a multivalent spacer group that is directly bonded to the monovalent groups so as to link at least one ethylenically unsaturated group and at least one ligand functional group by a chain of at least six catenated atoms.

Described are filtration membranes that include a porous fluoropolymer membrane and thermally stable ionic groups; filters and filter components that include these filtration membranes; methods of making the filtration membranes, filters, and filter components; and method of using a filtration membrane, filter component, or filter to remove unwanted material from fluid.

The present disclosure provides methods for forming asymmetric membranes. More specifically, methods are provided for applying a polymerizable species to a porous substrate for forming a coated porous substrate. The coated porous substrate is exposed to an ultraviolet radiation source having a peak emission wavelength less than 340 nm to polymerize the polymerizable species forming a polymerized material retained within the porous substrate so that the concentration of polymerized material is greater at the first major surface than at the second major surface.

A pore-filled ion exchange polyelectrolyte composite membrane from which the surface ion exchange polyelectrolyte has been removed and a method of manufacturing the same are provided. The ion exchange polyelectrolyte composite membrane exhibits low film resistance and low in-plane-direction swelling degree, and has a smaller film-thickness than a commercial film, and thus, can be used for various purposes. In addition, since the pore-filled ion exchange polyelectrolyte composite membrane is continuously manufactured through a roll-to-roll process, the manufacturing process is simple, and manufacturing costs can be greatly reduced.