A membrane is a microporous sheet made of a blend of a first ultra high molecular weight polyolefin and a second ultra high molecular weight polyolefin. Each polyolefin has a molecular weight, both of those molecular weights are greater than 1 million, and one molecular weight is greater than the other. Additionally, the intrinsic viscosity (IV) of the membrane may be greater than or equal to 6.3.

An ultra high molecular weight polyethylene (UHMWPE) membrane has at least one nanoporous UHMWPE film, where each of the nanoporous UHMWPE film is biaxial oriented with a thickness of 0.1 to 12 m and pores that exclude particles in excess of 10 nm with a total porosity of 65 to 75 percent. The nanoporous UHMWPE film can be coated or laminated by a hydrophilic polymer to form a Janus membrane and can be made with a multilayer composite structure. The UHMWPE membrane can be used in a device for molecular distillation (MD), reverse osmosis (RO), or forward osmosis (FO).

A two-layer photo-responsive membrane including a polymer layer and a support layer, the polymer layer being disposed on a surface of the support layer. The polymer layer is formed of a graft copolymer that contains a hydrophobic backbone and multiple side chains, the side chains each consisting of repeat units that switch between a hydrophobic form and a hydrophilic form upon exposure to a light of a specific wavelength. The polymer layer has a molecular weight cut-off of 3,000 to 250,000 Daltons and a thickness of 50 nm to 10 m; and the support layer has a molecular weight cut-off of 50 to 250,000 Daltons. Also disclosed is a method of preparing this two-layer photo-responsive membrane.

Disclosed are compositions that may be useful for forming synthetic membranes, methods of forming membranes therefrom, and membranes. In an embodiment, a membrane comprises a free hydrophilic polymer comprising a polyoxazoline, and a polyurethane, the polyurethane comprising a backbone comprising the reaction product of a diisocyanate, a polymeric aliphatic 5 diol, and optionally a chain extender.

A method of producing a hollow fiber membrane having an outside coating with a thin film composite (TFC) layer with a transmembrane protein, the method including the steps of: preparing an aqueous solution including a self-assembled nanostructure including polyalkyleneimine (PAI) and a detergent solubilized transmembrane protein and a di- or triamine, preparing an apolar solution including a di- or triacyl halide in an apolar organic solvent, contacting a hollow fiber membrane with the either the solution according to step a) or the solution according to step b), removing excess solution if any, contacting the hollow fiber membrane with the other solution, allowing an interfacial polymerization reaction to take place, and rinsing the hollow fiber membrane with an aqueous solvent. The hollow fiber is applicable e.g. for extracting water from the product solution.

Microporous sheet product and methods of making and using the same. In one embodiment, the microporous sheet product is made by a process that includes melt-extruding a sheet material using an extrusion mixture that includes (i) a cyclic olefin copolymer, (ii) an electrolyte swellable thermoplastic, and (iii) a compatibilizing agent that promotes mixing of the cyclic olefin copolymer and the electrolyte swellable thermoplastic, the compatibilizing agent having a boiling point in the range of 135-300 C. As an example, the cyclic olefin copolymer may be an ethylene-norbornene copolymer, the electrolyte swellable thermoplastic may be polyethylene oxide, and the compatibilizing agent may be mineral spirits. After extrusion, the sheet material may be cooled, and the compatibilizing agent may be removed, forming an ionically-conductive microporous sheet product. The microporous sheet product has high-temperature stability and gels when exposed to a liquid electrolyte, enabling high ionic conductivity when used as a battery separator.

Polymer membranes include a polymer material that is selectively permeable to acidic gases over methane in a gas stream, such as natural gas. The polymer material may be a polymer membrane comprising a fluorinated polytriazole polymer. The fluorinated polytriazole polymer may further comprise a substituted phenyl or a substituted benzenaminyl. The substituted phenyl or substituted benzenaminyl may be substituted with hydrogen, bromo, fluoro, chloro, iodo, hydroxy, methyl, trifluoromethyl, dimethylamino, tert-butyl, or difluoromethoxy groups. The polymer material may have a degree of polymerization of from 100 to 175. The polymer membranes may be incorporated into systems or methods for removing separable gases, such as acidic gases, from gas streams, such as natural gas.

Provided are UHMW polymers having a molecular weight of 500 kg/mol or greater. The UHMW polymers can be block copolymers, homopolymers, and random/statistical copolymers. The UHMW polymers can be used to form porous layers, which may be used in filtration membranes, such as, for example, ultrafiltration membranes. The filtration membranes can be used in various separation methods.

The invention provides a high permeance and high selectivity facilitated transport membrane comprising a very small pore, nanoporous polyethersulfone (PES)/polyvinylpyrrolidone (PVP) blend support membrane, a hydrophilic polymer inside the very small nanopores on the skin layer surface of the support membrane, a thin, nonporous, hydrophilic polymer layer coated on the surface of the support membrane, and metal salts incorporated in the hydrophilic polymer layer coated on the surface of the support membrane and the hydrophilic polymer inside the very small nanopores, a method of making this membrane, and the use of this membrane for olefin/paraffin separations, particularly for propylene/propane and ethylene/ethane separations.

A Polyvinylidene fluoride-based microporous membrane comprising: a substrate film; and the following microporous membrane, wherein the microporous membrane is an asymmetric membrane, and has a skin layer in which micropores are formed and a support layer which supports the skin layer and in which pores larger than the micropores are formed, a material of the microporous membrane is a polyvinylidene fluoride-based resin, the skin layer has a plurality of spherical bodies, a plurality of linear binding materials extend three-dimensionally from the respective spherical bodies, the adjacent spherical bodies are connected with each other by the linear binding materials to form a three-dimensional network structure where the spherical bodies serve as intersections, and the number of defects (the number of colored coarse voids) is less than 20.