Abstract: A semipermeable membrane support includes, a non-woven fabric including main fiber and binder fiber, both of which are formed of synthetic resin fine fiber, the non-woven fabric being manufactured by heating and pressing after paper making, wherein the semipermeable membrane support has a ratio of a tensile strength in a paper feeding direction to that in a width direction of 2:1 to 1:1.

Abstract: A method of treating blood or plasma of a subject to remove metabolic contaminants by electrophoresis. Blood or plasma from the subject is placed in a first solvent stream, the first solvent stream being separated form a second solvent stream by an electrophoretic membrane. Applying an electric potential between the two solvent streams causes movement of metabolic contaminants from the blood or plasma through the membrane into the second solvent stream while cellular and biomolecular components of the blood or plasma are substantially retained in the first sample stream, or if entering the membrane, being substantially prevented from entering the second solvent stream.

Abstract: The present invention relates to an asymmetric porous polytetrafluoroethylene membrane comprising a dense skin layer and a continuously foamed porous layer, (1) the dense skin layer having a surface roughness Ra of 20 to 165 nm; (2) the dense skin layer having a contact angle for water of 120 to 135°; (3) the porous layer having a maximum pore diameter of 0.03 to 1.0 ?m; and (4) the membrane having a total porosity of 20 to 70%. The asymmetric porous PTFE membrane has an ability to separate each liquid component from a liquid-liquid homogeneous mixture in addition to known properties such as water permeability resistance, gas permeability, sealing property and electric property, wherein change of these properties over time is small.

Abstract: The present invention provides a positively charged microporous membrane having a protein binding capacity of about 25 mg/ml or greater comprising a hydrophilic porous substrate and a crosslinked coating that provides a fixed positive charge to the membrane. The present invention further provides a positively charged microporous membrane comprising a porous substrate and a crosslinked coating comprising pendant cationic groups. The membranes of the present invention find use in a variety of applications including ion-exchange chromatography, macromolecular transfer, as well as detection, filtration and purification of biomolecules such as proteins, nucleic acids, endotoxins, and the like.

Abstract: The present invention provides, in certain embodiments, a negatively charged microporous membrane comprising a porous substrate and a crosslinked coating having fixed negative charges. The crosslinked coating can be prepared, e.g., from a polymerized composition comprising an unsaturated monomer having an anionic group, an N-(hydroxymethyl)- and/or N-(alkoxymethyl)-acrylamide, a hydrophilic unsaturated monomer, and an initiator. The present invention further provides, in some embodiments, a negatively charged microporous membrane comprising a porous substrate and a crosslinked coating prepared from a polymerized composition comprising an unsaturated monomer having an anionic group, an N-(hydroxymethyl)- or N-(alkoxymethyl)-acrylamide, a polysaccharide, and an initiator. The membranes of the present invention are suitable for use in ion exchange chromatography, for example, in the separation and purification of positively charged species such as proteins.

Abstract: The present invention relates to polymer films and a polymer membrane having an improved mechanical property profile produced therefrom, to a process for producing them and to their use.

Abstract: A method for creating a highly breathable and waterproof fabric based on hydrophobic plastic (such as PVDF) as a membrane layer. This new fabric allows higher water vapor throughput and better water resistance than other PVDF and ePTFE membranes. This is achieved through control of pore size, thus creating a spongy porous structure, pre-stressing to make the membrane and subsequent laminated fabric soft, and a microscopically folded structure which increases the surface area for the porous media, thus gaining higher throughput, waterproofness and comfort. In addition, the invention provides a method of controlling pore size distribution, increased porosity and pre-stress relief during the gelation proces.

Abstract: A microporous gas permeable membrane having an ultraphobic liquid contact surface. In the invention, ultraphobic surface is provided on the liquid contact surface of the membrane. In an embodiment of the invention, the ultraphobic surface includes a multiplicity of closely spaced microscale to nanoscale asperities formed on a substrate. When liquid at or below a predetermined pressure value is contacted with the ultraphobic liquid contact surface of the membrane, the liquid is “suspended” at the tops of the asperities, defining a liquid/gas interface plane. The area of the liquid/gas interface plane includes the area of the ultraphobic surface as well as the combined area of the micropores, so that the gas transfer rate and efficiency of the membrane is enhanced over prior membranes wherein the liquid/gas interfacial area is limited to only the area of the micropores.

Abstract: The present invention relates to nanofiltration and reverse osmosis membranes that may be used in a number of commercial applications in which a contaminant, such as salt, must be separated from a feed fluid, such as brackish water, to yield a purified product fluid, as well as a method for manufacturing such membranes. According to embodiments of the invention, an aqueous amine solution including an amine, an organic acid (e.g., propionic acid) and a non-amine base is applied to the surface of a porous substrate. A second solution containing an acyl halide and an organic solvent immiscible in water is then applied to the aqueous amine solution to cause interfacial polymerization to occur. The resulting membranes exhibit superior salt rejection and flux properties.

Abstract: The present invention provides a positively charged microporous membrane having a protein binding capacity of about 25 mg/ml or greater comprising a hydrophilic porous substrate and a crosslinked coating that provides a fixed positive charge to the membrane. The present invention further provides a positively charged microporous membrane comprising a porous substrate and a crosslinked coating comprising pendant cationic groups. The membranes of the present invention find use in a variety of applications including ion-exchange chromatography, macromolecular transfer, as well as detection, filtration and purification of biomolecules such as proteins, nucleic acids, endotoxins, and the like.

Abstract: A porous inorganic membrane comprises at least one inorganic phase having separating properties. Said membrane has a carbon content representing 0.05% to 25% by weight with respect to the mass of said inorganic phase and is selective to non-condensable gases. It is obtained by means of a selectivation treatment of a porous carbon-free inorganic membrane using a hydrocarbon feed. It is used in processes for separating non-condensable molecules such as hydrogen, and in association with a catalyst in a catalytic membrane reactor.

Abstract: This invention relates to porous formed bodies, especially membranes, with a novel porous structure on the basis of thermoplastic polymers, and to a method for producing such formed bodies and especially membranes. Membranes of this type can be used as filtration membranes.

Abstract: The invention is directed to copolymers, which can be formed into water vapor permeable, water resistant membranes suitable for use in garments, tents, etc. A copolymer includes a random distribution of a soft segment comprising a hydrophilic soft segment and up to about 30 wt % of a hydrophobic soft segment, a hard segment, a cross-linking segment comprising a pendant alkoxysilane, and at least two terminal groups comprising at least one of an amine and an isocyanate having a functionality of at least 2, wherein a number average molecular weight (Mn) of the copolymer is at least about 10,000.

Abstract: Described is a supported zeolite membrane that consists of a zeolite/substrate composite layer that exhibits, in the n-butane/isobutane separation, a permeance of n-butane of at least 6.10−7 mol/m2.s.Pa and a selectivity of at least 250 at the temperature of 180° C. Said zeolite/substrate composite layer is thin and continuous. This membrane is used in processes for gas separation, vapor separation and liquid separation.

Abstract: The invention includes novel anion exchange membranes formed by in situ polymerization of at least one monomer, polymer or copolymer on a woven support membrane and their methods of formation. The woven support membrane is preferably a woven PVC membrane. The invention also includes novel cation exchange membranes with or without woven support membranes and their methods of formation. The invention encompasses a process for using the membranes in electrodialysis of ionic solutions and in particular industrial effluents or brackish water or seawater. The electrodialysis process need not include a step to remove excess ions prior to electrodialysis and produces less waste by-product and/or by-products which can be recycled.

Abstract: The present application discloses a lithium-ion battery using heat-activatable microporous membrane which comprises a hot-melt adhesive, an engineering plastics, a tackifier and a filler. It also discloses methods of preparing such microporous membrane and the lithium-ion batteries. The battery built with the use of the microporous membrane of the present invention shows high rate capability, long cycle life, and low as well as stable impedance during charge-discharge cycling. The microporous membrane of the present invention also shows thermal shutdown behavior.

Abstract: The present invention pertains to methods and apparatus for removal of one or more solutes from a supercritical process solution. Solute additives and contaminants are removed from supercritical processing solutions via a contaminant removal system that is either part of the process vessel itself or is part of a local recirculation loop in fluid communication with the process vessel. This invention provides supercritical processing methods and apparatus for the removal of additives and contaminants during circulation so that depressurization and substrate removal can occur without contamination. The removal in some cases, for example cleaning residue, can be done continuously during a process to improve its efficiency. Removal mechanisms may include separation, destruction, conversion of the contaminant to acceptable species, or combinations thereof.

Abstract: The present invention relates to a filter element having a non-porous extrusion laminated strip formed on at least one edge and at least one side of a membrane. The strip is used to provide a means for ensuring a good bond between the filter element and the material into which it is potted. The strip is formed by the use of one or more extrusion heads that apply molten or softened polymer to one or both of the surfaces of the filter in a width and height desired. The strip is then subjected to pressure such as through a nip to at least partially embed the polymer strip into the filter pores so as to create a strong mechanical bond between the strip and the filter element. Additionally, it allows for the simultaneous formation of more than one membrane with the edge lamination at the same time.

Abstract: A process for imparting hydrophilic properties to a polymeric membrane by exposing the membrane to an acrylate monomer containing hydrophilic segments, such as ethylene oxide, and a hydrophilic functional group, a diacrylate monomer containing hydrophilic functional groups, and an initiator for facilitating crosslinking and polymerization reactions.

Abstract: The present invention provides a positively charged microporous membrane having a protein binding capacity about 25 mg/ml or greater comprising a hydrophilic porous substrate and a crosslinked coating that provides a fixed positive charge to the membrane. The present invention further provides a positively charged microporous membrane comprising a porous substrate and a crosslinked coating comprising pendant cationic groups. The membranes of the present invention find use in a variety of applications including ion-exchange chromatography, macromolecular transfer, as well as detection, filtration and purification of biomolecules such as proteins, nucleic acids, endotoxins, and the like.

Abstract: A filter for providing potable water is provided. The filter includes a housing having an inlet and an outlet, a filter material disposed within the housing, the filter material formed at least in part from a plurality of mesoporous, basic, and reduced-oxygen activated carbon filter particles. Preferably, at least some of the mesoporous activated carbon filter particles are coated with silver or a silver containing material. Kits comprising filters and information relating to the killing or removal of bacteria, viruses, and microbials are also provided.

Abstract: The present invention relates to a composite semipermeable membrane, which is useful as a reverse osmosis membrane or a nano-filtration membrane and comprises a polysulfone porous support membrane and a polyamide ultrathin layer formed on one of the surfaces of the porous support membrane, the composite membrane having the characteristic that in the infrared absorption spectrum obtained from the surface of a polyamide ultrathin layer of the composite semipermeable membrane, the ratio T (=Aa/As) of absorption intensity Aa at the absorption peak revealing C═O of polyamide in the region of 1600-1700 cm−1 to absorption intensity As at the absorption peak revealing polysulfone at a wavenumber around 1586 cm−1 is at least 0.05 and not higher than 3.

Abstract: An at least two layer, unsupported, continuous microporous membrane is disclosed. The at least two layer, unsupported, continuous microporous membrane may include at least two different membrane pore size layers or the pore sizes may have about the same pore size. Apparatus and processes for fabricating at least a two layer unsupported, continuous, microporous membrane are also disclosed.

Abstract: The present invention relates to polymer membranes for separating olefins from paraffins which have the similar molecular size and close boiling point. More particularly, it relates to a silver salt-containing facilitated transport membrane for olefin separation, and also a method for producing the same. An object of the present invention is to provide a silver salt-containing facilitated transport membrane for olefin separation having improved stability, and also a method for preparing the same, which exhibits no deterioration in membrane performance even when operated for an extended period of time.

Abstract: The filtering membranes of the present invention are made from a pair of polymer films stretched in a liquid surface-active medium for the formation of crazes filled with the aforementioned medium. The crazed films are perforated and then stack together in a stretched or released state and are welded together into a sealed structure with a plurality of parallel welding seams arranged, e.g., in mutually perpendicular directions, so that a plurality of sealed cells is formed. The cells have on one side of the membrane input openings and on the other side output openings. If an input opening is in one cell, then an output opening is in the adjacent cell. Adjacent cells are interconnected only through the welding seams. Welding can be carried out by contact heating or with the use of a laser beam, or the like. The material of the welding seam has an amorphous structure.

Abstract: The present invention provides integral porous membranes comprising an amorphous halopolymer, as well as processes for preparing the membranes, and devices comprising the membranes. An example of an amorphous halopolymer is a copolymer of tetrafluoroethylene and perfluoro-2,2-dimethyl-1,3-dioxole.

Abstract: An at least two zone, unsupported, continuous microporous membrane is disclosed. The at least two zone, unsupported, continuous microporous membrane may include at least two different membrane pore size zones or the pore sizes may have about the same pore size. Apparatus and processes for fabricating at least a two zone unsupported, continuous, microporous membrane are also disclosed.

Abstract: The invention relates to a membrane module in order to filter media which are capable of flowing. Said module incorporates an integrated heat exchanger. According to the invention, the membrane module has the following characteristics: a plurality of rod-shaped, porous, ceramic filter elements (1) (ceramic rods); the ceramic rods (1) are provided with continuous bores (1.1) located parallel to an axis; the ceramic rods are arranged parallel to each other and a lid (3, 4) covers the end thereof: the ceramic rods (1) are sealed at their circumferences against the lid (3, 4); a lid (3) located at one of the membrane modules is provided with an inlet (2.1) for the medium to be treated and a lid (4) located at the other end is provided with an outlet (2.

Abstract: Laser-induced phase-separation polymerization of a porous acrylate polymer is used for in-situ fabrication of dialysis membranes inside glass microchannels. A shaped 355 nm laser beam is used to produce a porous polymer membrane with a thickness of about 15 &mgr;m, which bonds to the glass microchannel and form a semi-permeable membrane. Differential permeation through a membrane formed with pentaerythritol triacrylate was observed and quantified by comparing the response of the membrane to fluorescein and fluorescently tagging 200 nm latex microspheres. Differential permeation was observed and quantified by comparing the response to rhodamine 560 and lactalbumin protein in a membrane formed with SPE-methylene bisacrylamide. The porous membranes illustrate the capability for the present technique to integrate sample cleanup into chip-based analysis systems.

Abstract: Solvent-resistant polybenzimidazole membranes, methods of making them and crosslinking them and composite membranes and hollow fiber membrane modules from them are disclosed.

Abstract: In a polyimide molded body, in particular a polyimide membrane which is functionalized with a chemical group and a method for production thereof, a molded body or membrane is obtained, whereby a pre-prepared polyimide body, as starting material, is brought into contact with an aqueous modifier solution for a period of 1 second to 1 hour. The modifier solution contains at least one modifier substance at least partially dissolved therein, which comprises a primary or secondary amino group, or a similar amino group and additionally at least one further functional group per molecule. The polyimide molded body is brought to an elevated temperature, either during the contact period with the modifier solution or thereafter and then purified and dried. The membrane obtained according to the invention may be functionalized in a targeted adjustable manner and has a high functionalization degree. The functionalization may be achieved simply and economically in an aqueous medium.

Abstract: A porous polymeric membrane formed from a blend of a polymeric membrane forming material, such as polyvinylidene fluoride or polysulfone and a polymeric reactivity modifying agent adapted to modify the surface active properties of the porous polymeric membrane. The reactivity modifying agent is preferably a linear polymeric anhydride, such as poly(alkyl vinyl ether/maleic anhydride). The surface activity modifications include modification of the hydrophilicity/hydrophobicity balance of the membrane, or hydrolysis followed by reaction with a polyamine to form a crosslinked polyamide layer. Such modified membranes have use as reverse osmosis membranes.

Abstract: A separation membrane module having hollow fibers, wherein a plurality of hollow fibers are heated and melted to bond and thermally fuse the external surfaces of the hollow fibers with each other; and a method of manufacturing a separation membrane module having hollow fibers whereby the ends of a plurality of hollow fibers are inserted into a sheath, the sheath and the hollow fibers are tightly bonded together to form spaces, and the sheath portion into which hollow fibers have been inserted is heated up to the temperature at which the surfaces of the hollow fibers melt, with the spaces thus formed kept in a decompressed state, so that the exterior surfaces of the hollow fibers are thermally fused and integrated together.

Abstract: In a method of filtration, a liquid to be filtered is brought into contact with the surface of a filter medium and is passed through the filter medium. A supernatant liquid layer is created on the surface of the filter medium, and the upper level of the liquid layer is suitably controlled. A hydraulic path is organized in the liquid layer, and a stream of the liquid to be treated is brought to the inlet of the hydraulic path. Liquid that has passed through the filter medium is recovered for n cycles by reinjecting the liquid into the supernatant layer at the outlet of the hydraulic path, producing in a section of the path a meeting of two opposed streams. The treated liquid is then drawn off after n cycles.

Abstract: A process for preparing a graft copolymer membrane is provided comprising exposing a polymeric base film to a dose of ionizing radiation, and then contacting the irradiated base film with an emulsion comprising a fluorostyrenic monomer.

Abstract: A filter for removing leukocytes from blood comprises a filter media enclosed in a housing. The filter media includes a main filter region comprising a porous membrane structure extending between first and second skin surfaces. The porous membrane structure is formed by intersecting cells having a range of diameters. The cells adjacent to the first skin surface have diameters generally smaller than the diameters of the cells adjacent to the second skin surface. The first skin surface includes an open area defined by pores, which are formed by the intersection of cells with the first skin surface. The majority of the open area is defined by pores having a diameter of between about 12 &mgr;m and 28 &mgr;m.

Abstract: A charge mosaic membrane having excellent selective permeability comprises a cationic polymer component, an anionic polymer component and a matrix component. Both of the cationic polymer component and the anionic polymer component are crosslinked particulate polymers. The matrix component is at least one polymer selected from a polysulfone resin, a polyarylate resin, a polyamide resin, a polyimide resin, a polyamideimide resin, a polyurethane resin, a fluorinated resin or a silicone resin. The charge mosaic membrane can be easily produced by conducting formation of the membrane by using a composition in which the cationic polymer component and the anionic polymer component are both dispersed in a solution of the matrix component in an organic solvent.

Abstract: The present invention provides porous media or membranes having a surface coating that includes a first coating of a cross-linked terpolymer and a second coating comprising a copolymer or a terpolymer modified with a hydrophilic or hydrophobic functional group which has a superior combination of properties, including heat stable biomolecule resistant adsorptive properties, resistance to strong alkaline solutions, and low levels of extractable matter.

Abstract: A hydrogen permselective membrane, a method of forming a permselective membrane and an apparatus comprising a permselective membrane, a porous substrate and an optional intermediate layer are described. Using chemical vapor deposition (CVD) at low reactant gas concentration, high permselectivities are achieved with minimal reduction in hydrogen permeance.

Abstract: The invention provides an implantable membrane for regulating the transport of analytes therethrough that includes a matrix including a first polymer; and a second polymer dispersed throughout the matrix, wherein the second polymer forms a network of microdomains which when hydrated are not observable using photomicroscopy at 400× magnification or less. In one aspect, the homogeneous membrane of the present invention has hydrophilic domains dispersed substantially throughout a hydrophobic matrix to provide an optimum balance between oxygen and glucose transport to an electrochemical glucose sensor.

Abstract: A microporous asymmetrical membrane formed of one or more layers wherein the “tight” side of the membrane has an “opened” face or otherwise highly-porous reticulated surface is described. The microporous asymmetrical membrane has high throughput and high flux, even when used for filtering viscous materials, such as serum or plasma. The membrane's surface can be formed by ablation or solvation, or in a two or more layered structure, through an appropriate selection of casting dopes.

Abstract: This invention provides a process for making microporous membranes from a polymer solution and the membranes therefrom. A thermal assist, such as heating of the polymer solution can be effected subsequent to shaping the solution, such as by forming a film, tube or hollow fiber of the solution under conditions that do not cause phase separation.. In a preferred embodiment, the formed solution is briefly heated to generate a temperature gradient through the body of the formed solution. The polymer in solution then is precipitated to form a microporous structure. The formation of a wide variety of symmetric and asymmetric structures can be obtained using this process. Higher temperatures and/or longer heating times effected during the heating step result in larger pore sizes and different pore gradients in the final membrane product.

Abstract: An ultrafiltration membrane is modified to exhibit low protein fouling and yet maintains a greater fraction of the original membrane permeability and retention properties after modification. This is achieved by grafting monomer onto the surface of a highly photoactive membrane such as polyethersulfone, via the process of dipping the polymeric membrane into a solution containing one or more monomers and a chain transfer agent, removing the membrane from the solution, securing the membrane inside of a quartz vessel contained within another vessel of liquid filter, and irradiating the membrane with a UV light at a wavelength between the range of 280 nm and 300 nm. High density grafting and shorter grafted monomer chain length result in low protein fouling and retention of permeability.

Abstract: High flux porous hollow fiber membranes are produced from perfluorinated thermoplastic polymers by extruding a heated solution of the polymer having a lower critical solution temperature directly into a cooling bath to form the porous membrane by liquid-liquid phase separation. Extrusion can be conducted either vertically or horizontally.

Abstract: The present invention relates to filtration media having both hydrophobic (water-repellent) properties. The filtration media are produced using a fluorothermoplastic material, such as a terpolymer of tetrafluoroethylene, vinylidene fluoride, and hexafluoropropylene. The invention also relates to methods of preparing such filtration media using casting solution phase inversion.

Abstract: A filter unit for removing leukocytes from a leukocyte-containing suspension by passing the suspension through a filter unit. The filter unit may comprise a main filter for blocking the leukocytes and a post-filter for preventing leakage of the leukocytes having a higher median pore size than the main filter and placed downstream of the main-filter.

Abstract: Solvent-resistant polybenzimidazole membranes, methods of making them and crosslinking them and composite membranes and hollow fiber membrane modules from them are disclosed.

Abstract: The invention relates to a method for producing a hydrolytically stable polyamide membrane having an open-pored, microporous and sponge-like support-layer structure, using a process involving thermally induced liquid-liquid phase separation. A solution of an aliphatic polyamide in a solvent system, comprising preferably a solvent and a non-solvent for the polyamide, is extruded to form a shaped object. After leaving the die, the shaped object is cooled by means of a cooling medium until phase separation occurs and the polymer-rich phase solidifies to form the membrane structure. The solution of the polyamide in the solvent system contains an antioxidant agent as a stabiliser for the polyamide which, together with the solvent system, is selected in a way that the antioxidant agent is essentially insoluble in the solvent system at the phase separation temperature.

Abstract: A membrane includes a blend of two or more polymers such that under operating conditions of a separation using the membrane the operating temperature is greater than at least one glass transition temperature of the blend. A membrane includes a blend of polymers exhibiting calculated &dgr;a of the membrane material value is greater than 7.5. A membrane includes a blend of polymers exhibiting a calculated solubility selectivity for a separation of interest greater than 1. A membrane includes a blend of polymers having polar functional groups and non-polar functional groups wherein the composition of the blend is selected so that the interaction of the polar functional groups and the non-polar functional groups with a permeating species leads to preferential solubility selectivity. A polymer blend for performing a separation includes at least one rubbery polymer having a glass transition temperature no greater than 20° C. and at least one glassy polymer having a glass transition temperature above 20° C.

Abstract: A dialyzer for blood treatment includes a semipermeable membrane which is made of a hydrophobic polymer and a hydrophilic polymer, and has a water permeating performance drying of ½ or higher relative to that before drying. The dialyzer has a vitamin B12 clearance not smaller than 135 ml/min per 1.6 m2 or the amount of the hydrophilic polymer eluted from the semipermeable membrane is not higher than 10 ppm. A dialyzer for blood treatment is light-weight, easy to handle, and exhibits a reduced elution of the hydrophilic polymer procedures for producing a dialyzer containing the semipermeable membrane and a process for producing a hollow fiber membrane for use in blood treatment as described.