Abstract: The present invention aims at providing a composite semipermeable membrane in which water permeability and salt-blocking rate cannot deteriorate by long-term storage, and at providing a process for producing the same. The present invention relates to a composite semipermeable membrane having a skin layer formed on the surface of a porous support, the skin layer including a polyamide resin obtained by interfacial polymerization of a polyfunctional amine component and a polyfunctional acid halide component, wherein the porous support contains at least one kind of additives selected from the group consisting of antioxidants, antibacterial agents, antifungal agents, and moisturizers, in an amount of 95% by weight or more with respect to the whole composite semipermeable membrane.

Abstract: A flexible porous free-standing protein membrane includes cross-linked protein. At least part of pores of the porous membrane is formed by removing nanostrands whose diameters are 2-3 nm, the cross-linked protein is cross-linked by a bifunctional cross-linker, and a thickness of the protein membrane is 10 ?m or less.

Abstract: Method for preparing a filtration membrane and a filtration membrane prepared by the method. According to one embodiment, the method involves casting a polymer solution onto a porous support to form a coated support. The coated support is then quenched to form a membrane/support composite, and the membrane/support composite is then dried. Next, a first end of a first piece of adhesive tape is applied to the membrane side of the composite, and the second end of the first piece of adhesive tape is applied to a first rotatable winder. In addition, a first end of a second piece of adhesive tape is applied to the support side of the composite, and the second end of the second piece of adhesive tape is applied to a second rotatable winder. The two winders are then rotated so as to pull apart the membrane from the support.

Abstract: A hollow fiber membrane is produced through a thermally induced phase separation process by dissolving a highly hydrophilic polyamide resin in a high-boiling-point solvent such as an aprotic polar solvent at a temperature of not lower than 100° C. The hollow fiber membrane has a membrane surface having a water contact angle of not greater than 80 degrees, and has a water permeability of not less than 100 L/m2·atm·h and a 0.1-?m particle rejection percentage of not less than 90%.

Abstract: A process for preparing a reverse osmosis membrane that includes: (A) providing a polyamine, a polyfunctional acid halide, and a flux increasing additive having the formula Z+B? where Z+ is an easily dissociable cation and B? is a beta-diketonate; (B) combining the polyamine, polyfunctional acid halide, and flux increasing additive on the surface of a porous support membrane; and (C) interfacially polymerizing the polyamine and the polyfunctional acid halide, and flux increasing additive on the surface of the porous support membrane to form a reverse osmosis membrane comprising (i) the porous support membrane and (ii) a discrimination layer comprising a polyamide. The reverse osmosis membrane is characterized by a flux that is greater than the flux of the same membrane prepared in the absence of the flux increasing additive.

Abstract: A method comprises disposing, on a porous support membrane, an aqueous mixture comprising a crosslinkable polymer comprising a poly(meth)acrylate and/or poly(meth)acrylamide backbone, thereby forming an initial film layer, wherein the crosslinkable polymer comprises a side chain nucleophilic amine group capable of interfacially reacting with a multi-functional acid halide crosslinking agent to form a crosslinked polymer; contacting the initial film layer with a mixture comprising i) the multi-functional acid halide crosslinking agent, ii) an optional accelerator, and iii) an organic solvent, the organic solvent being a non-solvent for the crosslinkable polymer; and allowing the crosslinkable polymer to interfacially react with the crosslinking agent, thereby forming a composite filtration membrane comprising an anti-fouling selective layer comprising the crosslinked polymer.

Abstract: The invention relates to a nanofiber membrane layer having a basis weight of 0.01-50 g/m2 and a porosity of 60-95%, comprising a nanoweb made of polymeric nanofibers with a number average diameter in the range of 50-600 nm, consisting of a polymer composition comprising a semicrystalline polyamide having a C/N ratio of at most 5.5. The invention also relates to water and air filtration devices comprising such a nanofiber membrane layer.

Abstract: Composite membranes including a coating of polyalkylene oxide and oxy-substituted phenyl compounds along with various methods for making and using the same. In one embodiment, the composite membrane comprises a thin film polyamide layer including a coating of a reaction product of a polyalkylene oxide compound and an oxy-substituted phenyl compound. In another embodiment, the coating comprises a polymer including alkylene oxide repeating units and one or more oxy-substituted phenyl functional groups.

Abstract: Technologies are generally described for composite membranes which may include a porous graphene layer in contact with a porous support substrate. In various examples, a surface of the porous support substrate may include at least one of: a thermo-formed polymer characterized by a glass transition temperature, a woven fibrous membrane, and/or a nonwoven fibrous membrane. Examples of the composite membranes permit the use of highly porous woven or nonwoven fibrous support membranes instead of intermediate porous membrane supports. In several examples, the composite membranes may include porous graphene layers directly laminated onto the fibrous membranes via the thermo-formed polymers. The described composite membranes may be useful for separations, for example, of gases, liquids and solutions.

Abstract: Composite membranes including a coating of polyalkylene oxide and biguanide compounds along with various methods for making and using the same. In one embodiment, the composite membrane comprises a thin film polyamide layer including a coating of a reaction product of a polyalkylene oxide compound and a biguanide-type compound. In another embodiment, the coating comprises a polymer including alkylene oxide repeating units and one or more biguanide functional groups.

Abstract: The present invention generally relates to gas separation membranes and, in particular, to high selectivity fluorinated ethylene-propylene polymer-comprising polymeric blend membranes for gas separations. The polymeric blend membrane comprises a fluorinated ethylene-propylene polymer and a second polymer different from the fluorinated ethylene-propylene polymer. The fluorinated ethylene-propylene polymers in the current invention are copolymers comprising 10 to 99 mol % 2,3,3,3-tetrafluoropropene-based structural units and 1 to 90 mol % vinylidene fluoride-based structural units. The second polymer different from the fluorinated ethylene-propylene polymer is selected from a low cost, easily processable glassy polymer.

Abstract: Composite membranes including a coating of polyalkylene oxide and acetophenone compounds along with various methods for making and using the same. In one embodiment, the composite membrane comprises a thin film polyamide layer including a coating of a reaction product of a polyalkylene oxide compound and an acetophenone compound. In another embodiment, the coating comprises a polymer including alkylene oxide repeating units and one or more acetophenone functional groups.

Abstract: A method of making a water vapor transport membrane is described. The method can include providing two sheets, each sheet comprising a support layer with an ionomer layer thereon; applying a solvent to at least one sheet; and contacting the ionomer layers of the two sheets to form a composite membrane comprising a composite ionomer layer between the two support layers. A composite membrane is also described.

Abstract: A polyamide membrane including reaction product of an anhydrous solution comprising an anhydrous solvent, at least one polyfunctional secondary amine and a pre-polymer deposition catalyst, and an anhydrous, organic solvent solution comprising a polyfunctional aromatic amine-reactive reactant having one ring. A composite semipermeable membrane including the polyamide membrane on a porous support.

Abstract: It is an object of the present invention to provide a composite semipermeable membrane having an excellent resistance property to contamination, particularly an excellent resistance property to microbial contamination, and a water treatment method using the composite semipermeable membrane. The present invention relates to a composite semipermeable membrane comprising a skin layer formed on the surface of a porous support and containing a polyamide-based resin obtained by reacting a polyfunctional amine component with a polyfunctional acid halide component, wherein an antibacterial layer containing a silver-based antibacterial agent and a polymer component is formed on the skin layer directly or with other layer interposed therebetween, and the weight ratio between the silver-based antibacterial agent and the polymer component in the antibacterial layer is 55:45 to 95:5 (silver-based antibacterial agent:polymer component).

Abstract: The present disclosure describes an additive that may be used in the manufacture of thin-film polyamide composite membranes. Thin-film polyamide composite membranes are used in filtration processes, such as reverse osmosis and nanofiltration. The additive may be an amino-siloxane compound. The amino-siloxane compound includes repeated groups of silicon bonded to oxygen with at least one amine functional group. Optionally, the amino-siloxane compound may also include a hydrophilic group. The additive reacts with an aqueous phase and an organic phase to form a thin polyamide film on a porous substrate.

Abstract: A polymeric membrane for separating oil from water has a pore size of 0.005 ?m to 5 ?m, a thickness of 50 ?m to 1,000 ?m, a water contact angle of 0° to 60°, an oil contact angle of 40° to 100°. The membrane contains a hydrophobic matrix polymer and a functional polymer that contains a hydrophobic backbone and side chains. The side chains each have an oleophobic terminal segment and a hydrophilic internal segment. The weight ratio of the matrix polymer to the functional polymer is 99:1 to 1:9. Also disclosed is a method of making the above described membrane.

Abstract: A chlorine resistant polyamide is formed from the reaction product of an amine and an acid chloride monomer wherein both the amine and the acid chloride monomer are modified with electron-withdrawing groups that exhibit sufficient activity to (i) minimize any chlorination on both the amine and acid chloride and (ii) minimize N-chlorination. A membrane is made from the polyamide for use, for example, in a desalination unit.

Abstract: Composite membranes including a coating comprising a combination of polyalkylene oxide and imidazol compounds along with various methods for making and using the same. In one embodiment, the composite membrane comprises a thin film polyamide layer including a coating of a reaction product of a polyalkylene oxide compound and an imidazol compound. In another embodiment, the coating comprises a polymer including alkylene oxide repeating units and one or more imidazol functional groups.

Abstract: A reverse osmosis membrane includes a porous support, a polyamide active layer formed on the porous support, and a coating layer including a copolymer including an amphoteric ionic compound and glycidyl (meth)acrylate. The coating layer makes a chemical bond with the polyamide active layer. A method of manufacturing the reverse osmosis membrane also is disclosed.

Abstract: Composite membranes including a coating of polyalkylene oxide and triazine compounds along with various methods for making and using the same. In one embodiment, the composite membrane comprises a thin film polyamide layer including a coating of a reaction product of a polyalkylene oxide compound and a triazine compound.

Abstract: A composite semipermeable membrane comprising a porous support membrane on which a separating functional polyamide layer resulting from the polycondensation reaction of polyfunctional aromatic amines with polyfunctional acid halides is formed, wherein the separating functional polyamide layer has carboxy groups, amino groups, phenolic hydroxyl groups, and azo groups, wherein XA, the ratio of the amino groups (molar equivalent of the amino groups/(molar equivalent of the azo groups+molar equivalent of the phenolic hydroxyl groups+molar equivalent of the amino groups)) on a feed water contact surface of the separating functional polyamide layer (an A surface), is in the range 0.5 or less, and XB, the ratio of the amino groups (molar equivalent of the amino groups/(molar equivalent of the azo groups+molar equivalent of the phenolic hydroxyl groups+molar equivalent of the amino groups)) on a permeate-side surface of the separating functional polyamide layer (a B surface), i.e.

Abstract: Improved methods for reducing boron concentration in seawater or brackish water, while simultaneously maintaining or improving the salt rejection of membrane and flow performance of polyamide reverse osmosis (RO) membranes include contacting the water with a composite membrane comprising moieties derived from an aromatic sulfonyl halide, a heteroaromatic sulfonyl halide, a sulfinyl halide; a sulfenyl halide; a sulfuryl halide; a phosphoryl halide; a phosphonyl halide; a phosphinyl halide; a thiophosphoryl halide; a thiophosphonyl halide, an isocyanate, a urea, a cyanate, an aromatic carbonyl halide, an epoxide or a mixture thereof.

Abstract: The present disclosure describes a method for forming microporous membranes. More specifically, vapor induced phase separation techniques are used for forming multizone microporous membranes having improved material throughput.

Abstract: A conformal coating that resists fouling by waterborne contamination in aquatic environments, a method for fabricating the coating, and a filter having such a coating are disclosed. The coating comprises a hydrophilic polymer and a surfactant wherein the surfactant undergoes a phase change upon exposure to a saline solution. Also disclosed are in situ methods for regenerating anti-fouling filters having the fouling resistant coating.

Abstract: An electrochemical separation membrane and the manufacturing method thereof are disclosed. The method includes: a polymer solution preparing step to mix a polymer material, solvent and ceramic precursors thoroughly to form a polymer solution, wherein the polymer material and the ceramic precursors are dissolved uniformly in the solvent; a coating step to coat the polymer solution on a porous base material; a hydrolysis step to cause the porous base material coated with the polymer solution to contact an aqueous solution to hydrolyze the ceramic precursor into ceramic particles; and a drying step to remove the water and the solvent from the porous base material and in order to form the electrochemical separation membrane. The electrochemical separation membrane made of this method have better ion conductivity, interface stability and thermal stability based on the ceramic particles.

Abstract: A thin film composite membrane includes an active layer on a support membrane, wherein the active layer includes at least two chemically distinct first and second crosslinked polyamide film sub-layers. The first film sub-layer includes a polyamide unit; and the second film sub-layer includes a copolyamide with two chemically distinct polyamide units. The first film sub-layer is closer to the support than is the second film sub-layer.

Abstract: There is provided a composite semipermeable membrane that shows a high salt removal ratio and high performance in rejecting boron that is not dissociated in the neutral region. The composite semipermeable membrane is produced by a process that includes forming a separating functional polyamide layer on a porous substrate film, while using an organic solvent solution containing a specific cyclic aliphatic compound or a specific aromatic compound such that a polyamide molecule that forms the separating functional polyamide layer has a partial structure composed of “a cyclic aliphatic group or an aromatic group having at least two specific substituents, at least one of which contains a heteroatom bond and a carbonyl group at the ? or ? position”.

Abstract: The invention relates to a micro-porous membrane comprising a porous membrane carrier made of a first polymeric material (A) and comprising a second polymeric material (B) intimately divided throughout the porous membrane carrier, wherein the porous membrane carrier comprises a plurality of interconnected polymeric fibers, fibrils, filaments and/or lamellae having a thickness of less than 1 ?m, the porous membrane carrier has an interconnected open porous structure formed by the plurality of interconnected polymeric fibers, fibrils, filaments and/or lamellae and a porosity of at least 50%; and the polymeric material (B) comprises a thermoplastic polycondensation polymer and is present in an amount of at most 30 wt. %, relative to the total weight of (A) and (B).

Abstract: A process for producing a resilient ion exchange membrane. The process comprises the steps of (1) selecting a porous matrix, (2) saturating the porous matrix with a homogenous solution comprising a mixture of: (i) a hydrophilic ionic monomer, (ii) a hydrophobic cross-linking oligomer and/or a comonomer, (iii) a free radical initiator, and (iii) a solvent for solubilizing the hydrophilic ionic monomer, the hydrophobic cross-linking oligomer and/or comonomer, and the free radical initiator into a homogenous mixture.

Abstract: Processes for manufacturing a thin film composite membrane comprising multi-walled carbon nanotubes include contacting under interfacial polymerization conditions an organic solution comprising a polyacid halide with an aqueous solution comprising a polyamine to form a thin film composite membrane on a surface of a porous base membrane; at least one of the organic solution and the aqueous solution further including multi-walled carbon nanotubes having an outside diameter of less than about 30 nm.

Abstract: It is an object of the present invention to provide a composite semipermeable membrane having an excellent resistance property to contamination, particularly an excellent resistance property to microbial contamination, and a water treatment method using the composite semipermeable membrane. The present invention relates to a composite semipermeable membrane comprising a skin layer formed on the surface of a porous support and containing a polyamide-based resin obtained by reacting a polyfunctional amine component with a polyfunctional acid halide component, wherein an antibacterial layer containing a silver-based antibacterial agent and a polymer component is formed on the skin layer directly or with other layer interposed therebetween, and the weight ratio between the silver-based antibacterial agent and the polymer component in the antibacterial layer is 55:45 to 95:5 (silver-based antibacterial agent:polymer component).

Abstract: The present invention provides a composite membrane comprising a porous base membrane and a polyamide coating disposed on said porous base membrane, said polyamide coating comprising a C3-C8 cyclic carbonyl compound and a C1-C8 amide compound, said amide compound comprising at least one N—H moiety. In addition the present invention provides a method of preparing a composite membrane comprising contacting under interfacial polymerization conditions an organic solution comprising a polyacid halide with an aqueous solution comprising a polyamine, said contacting being carried out on a surface of a porous base membrane, said organic solution further comprising a C3-C8 cyclic carbonyl compound, said aqueous solution comprising a C1-C8 amide compound, said amide compound comprising at least one N—H moiety.

Abstract: There is disclosed a method for preparing a reverse osmosis membrane, the method including: forming a first coating layer by coating an aqueous amine solution on a surface of a microporous support to have a thickness of 20 ?m to 30 ?m; removing an excess of the aqueous amine solution from the microporous support; and forming a second coating layer by coating an aliphatic hydrocarbon-based organic solution including acyl halide on the first coating layer to have a thickness of 10 ?m to 30 ?m.

Abstract: A separation membrane for water treatment, comprising a porous layer that is obtained by a phase separation method using a solution containing a resin and at least one of either an N,N-disubstituted isobutylamide or an N-monosubstituted isobutylamide.

Abstract: A negatively charged microporous filtration medium having a high charge density comprising a porous substrate and a polymerized cross-linked polymeric coating located on the inner and outer surfaces of the substrate. The coating may be formed from a reactant solution comprising negatively charged cross-linkable polymerizeable acrylamidoalkyl monomers and acrylamido cross-linking agents which are polymerized in situ on the substrate. The negatively charged microporous filtration medium are suitable for use as prefiltration membranes for selectively removing protein aggregates from a protein solution.

Abstract: RO membranes using chlorinated water as a feed stream maybe protected from damage by the chlorine with a protective layer including reactive nitrogen which forms chloromines on the surface of the membrane that reduce chlorine penetration. This protective layer also provides substantial anti-fouling capabilities, whether used with a chlorinated or unchlorinated feed stream because the chloramines are anti-bacterial. Although chlorine is lost in use, the anti-fouling layer or coating can be recharged with additional chlorine without damaging the discrimination layer. The anti-fouling layer or coating may be advantageously used with Thin film composite, TFC, membranes for use in forward and reverse osmosis may include nanoparticles, monohydrolyzed and/or di-hydrolyzed TMC, and/or alkaline earth alkaline metal complexes or other additives.

Abstract: A method of photo-grafting onto a separation membrane a copolymer includes at least one of: and; For example, in Structure 1A, x1?2 and y1?1; R1 and R2 are independently selected from the group consisting of CH3 and H; R3 is independently selected from the group consisting of poly(oxyalkylene), quaternary ammonium salts, pyridinium salts, sulfonium salts, sulfobetaines, carboxybetaines, alcohols, phenols, tertiary amines, aryl groups; linear, branched and cyclic alkylenes; linear, branched and cyclic heteroalkylenes; linear, branched and cyclic fluoroalkylenes; and siloxyl; R4 is independently selected from the group consisting of linear, branched, and cyclic alkylenes; linear, branched and cyclic hetroalkylenes; linear, branched and cyclic fluoroalkylenes; phenyl; and siloxyl; and Z1 is 0 or 1.

Abstract: Provided is a composite semipermeable membrane, comprising: a microporous support membrane which comprises a substrate and a porous support, and a polyamide separation functional layer formed on the microporous support membrane, wherein the polyamide has an irreversible heat absorption, which is measured using temperature modulated DSC, of 275 J/g or more at a temperature in the range of ?20 to 150° C. in the first heating process. Provided is a high-performance composite semipermeable membrane having high chemical durability, high water permeation and high rejection.

Abstract: The invention relates to a membrane construction comprising multiple layers wherein at least one of the layers is a nanoweb made of polymeric nanofibers, wherein the mean flow pore size of the nanoweb is in the range from 50 nm to 5 ?m, wherein the number average diameter of the nanofibers is in the range from 100 to 600 nm, wherein the basis weight of the nanoweb is in the range from 1 to 20 g/m2, wherein the porosity of the nanoweb is in the range from 60 to 95%, wherein at least one of the layers is a support layer and wherein the nanoweb is hydrophilic.

Abstract: The present invention relates to a method of preparing RAFT, ATRP or NMRP functionalized thin film composite (TFC) polyamide membranes on a microporous substrate. A further aspect of the invention is the subsequent modification of the thin film composite polyamide membrane by controlled free radical polymerization (CFRP) to yield membranes having new chemical and physical properties, e.g. antifouling and/or antibacterial properties. Further aspects of the invention are the functionalized thin film composite (TFC) polyamide membranes on the microporous substrate itself and the membranes modified by controlled free radical polymerization.

Abstract: The present invention relates to a separation membrane for water treatment having high water flux and membrane contamination preventing characteristics, and a manufacturing method thereof. The separation membrane for water treatment according to the present invention includes a nanofiber wherein the separation membrane has a surface electric charge. According to the present invention, a separation membrane for water treatment having high water flux and membrane contamination preventing characteristics, and a manufacturing method thereof may be implemented.

Abstract: The present invention aims at providing a process for producing a dried composite semipermeable membrane having extremely small content of unreacted components, outstanding water permeability and salt-blocking rate even after drying treatment, and outstanding contamination resistance and durability.

Abstract: The invention relates to a process for membrane separation that makes it possible to separate linear hydrocarbons from branched hydrocarbons. The membrane that is used comprises a dense selective layer that consists of a polymer whose chemical structure contains at least one bis-phenyl-9,9-fluorene group.

Abstract: The present invention relates to surface modification of reverse osmosis membranes to introduce antifouling properties without compromising the separation properties of the original membranes. This approach utilizes: providing a coated membrane surface having enhanced hydrophilic characteristics that prevents the biofoulants from settling; have a surface that consists of hydrophilic brushes that unsettle any biofoulants that get through; and having antimicrobial ions present in the membrane coatings and able to remove or minimize any remaining biofoulants without leaching into the permeate. These coatings are made using dendritic polymers such as hyperbranched polymers or dendrimers.

Abstract: The present invention relates to a membrane being suitable for, for example, hemodialysis. Said membrane comprises at least one hydrophobic polymer and at least one hydrophilic polymer. According to the present invention the outer surface of the hollow fiber has pores in the range of 0.5-3 ?m and the numbers of said pores in the outer surface are in the range of 10,000 to 150,000 pores per mm2, preferably in the range of 18,000 to 100,000 pores per mm2, and most preferably in the range of 20,000 to 100,000 pores per mm2. The present invention further relates to a process for the preparation of said membrane and use of said membrane in hemodialysis, hemodiafiltration and hemofiltration, and in dialysis and filtration in general, for example in water purification or dehydration.

Abstract: One aspect of the present invention includes a membrane. The membrane includes a porous support and a polymeric layer disposed on the porous support. The membrane further includes a plurality of substantially hydrophobic mesoporous nanoparticles disposed within the polymeric layer. A water treatment system and a method of making a membrane are also presented.

Abstract: Forward osmosis membranes include an active layer and a thin support layer. A bilayer substrate including a removable backing layer may allow forward osmosis membranes with reduced supporting layer thickness to be processed on existing manufacturing lines.

Abstract: A reverse osmosis membrane that can maintain high permeability for a longer time, a reverse osmosis membrane apparatus, and a hydrophilic treatment method for a reverse osmosis membrane. A reverse osmosis membrane to which poly(vinyl alcohol) is absorbed, wherein the poly(vinyl alcohol) is an ionic poly(vinyl alcohol). Preferably, adsorption of a cationic PVA to the reverse osmosis membrane is followed by adsorption of an anionic PVA. More preferably, an ionic polymer other than PVA is also absorbed to the reverse osmosis membrane. A reverse osmosis membrane apparatus including the reverse osmosis membrane. A hydrophilic treatment method for a reverse osmosis membrane, involving bringing the reverse osmosis membrane into contact with an ionic poly(vinyl alcohol).

Abstract: In one aspect, the invention relates to engineered osmosis and related membrane-based separation technologies. Disclosed are semi-permeable nanostructured osmosis membranes comprising a film polymerized on a nanofiber support fabric, methods for osmotically-driven separation, the method comprising creating an osmotic pressure gradient across a semi-permeable nanostructured osmosis membrane comprising a film polymerized on a nanofiber support fabric, and methods of generating power comprising creating an osmotic pressure gradient across a semi-permeable nanostructured osmosis membrane comprising a film polymerized on a nanofiber support fabric. 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.