Abstract: An ionomer and a process for forming the ionomer such that the ionomer has (1) low equivalent weight (below 950, preferably between 625 and 850, and most preferably between 675 and 800) and (2) high conductivity (greater than 0.13 S/cm). In another embodiment, the invention is an ionomer having (1) low equivalent weight (below 950, preferably between 625 and 850, and most preferably between 675 and 800) and (2) acceptably low hydration (less than about 120 weight percent). These ionomers are capable of being processed into thin film and are extremely well-suited for low humidity or high temperature fuel cell applications.

Abstract: A hollow fiber microfiltration (MF) membrane is provided. The casting solution used to make this membrane includes a fiber-forming polymer having a degree of polymerization greater than about 1000, a water-soluble polymer, an anhydride with about 2 to 12 carbon atoms, and a solvent. The membrane is formed by mixing and heating these components to form a viscous dope and then extruding the dope through an annular orifice to form a hollow fiber MF membrane. The hollow fiber membrane is then fed through a coagulation bath and two leaching baths. The membrane is especially useful for filtering liquids, such as wine and juice, so as to remove bacteria, gel, and solid particles from the liquids.

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.

Abstract: There is provided a process for removing and recovering one or more unassociated phenolic compounds dissolved in aqueous fluid, the process comprising the steps of: (a) transferring the one or more unassociated phenolic compounds from the aqueous fluid to an alkaline stripping solution, wherein transfer of the one or more unassociated phenolic compounds from the aqueous fluid to the alkaline stripping solution occurs across a membrane; wherein the membrane is a non porous, selectively permeable membrane; (b) regulating the volume of alkaline stripping solution employed relative to the volume of aqueous fluid treated so that the total phenolic compound concentration in the alkaline stripping solution, comprising the sum of the dissociated and unassociated phenolic compound concentrations, is above the solubility of the phenolic compounds in the acidified stripping solution of step (d); (c) regulating the pH of the alkaline stripping solution in contact with the membrane to a value at least 0.

Abstract: The object of the present invention is to provide a lipid membrane whose permeability to substances is high and strongly correlated with the permeability of biomembranes to drugs and which therefore is suitable for rapid measurement.

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: A filter construction is provided having a packing density of at least 300 square meters of active membrane filter area per cubic meter of external volume of said filter construction, said filter constructed of materials characterized by less than 250 mg of extracted contamination per m2 of wetted material.

Abstract: A novel microporous membrane comprising a hot-melt adhesive and an engineering plastics, the methods of preparing such microporous membrane and the uses of the microporous membrane in, e.g., batteries, super capacitors, fuel cells, sensors, electrochromic devices or the like.

Abstract: The present invention relates to ultra-thin high strength asymmetric microfiltration and ultrafiltration cellulosic membranes. The membranes are internally hydrophilic. A method of preparing such membranes and their use in separating proteins from biological liquids are also provided.

Abstract: Cast semi-permeable membranes made from synthetic polymer used in reverse osmosis, ultrafiltration and microfiltration are treated with a non-leaching antimicrobial agent to prevent its bio-fouling and bacterial breakthrough. The semi-permeable membranes include a polymeric material and a non-leaching antimicrobial agent that is incorporated into and homogeneously distributed throughout the polymeric material. The polymeric material, in the case of one membrane, may be cellulose acetate. In the case of thin film composite polyamide membranes, the antimicrobial agent is incorporated in a microporous polysulfone layer that is sandwiched between a reinforcing fabric and an ultrathin polyamide material. The invention also includes a treatment of flat and hollow fiber semipermeable membranes made with polysulfones and polyvinylidene fluoride.

Abstract: A composite membrane is provided comprising a porous substrate membrane coated with a membrane comprising N-acetylated chitosan. The N-acetylated chitosan is characterized by a degree of N-acetylation greater than 50% and less than 90%. The porous substrate membrane includes any of polyvinylidene fluoride, polysulfone, and a ceramic. In this respect, composite membrane is provided comprising: a first layer including N-acetylated chitosan, and a second layer including a porous substrate membrane, wherein the first layer is coated upon the second layer. A method of forming a composite membrane is also provided comprising the steps of: forming a porous substrate membrane, depositing chitosan solution on the porous substrate membrane to form a first intermediate, drying the first intermediate to form an intermediate composite membrane including a chitosan membrane, and acetylating the chitosan membrane.

Abstract: The present invention includes methods for the production of a continuous differential permeable membrane and for devices that use such a membrane. One form of the present invention is a filtration apparatus having fluid permeable and fluid impermeable regions. The apparatus may be used allows for high throughout processes such as chemical synthesis and biological separations.

Abstract: A hollow fiber membrane made of an ethylene-vinyl alcohol polymer, comprises a dense layer existing in the inner surface and a porous layer existing in the layer other than the dense layer, wherein the hollow fiber membrane has a porosity of 60 to 90%, an overall mass transfer coefficient for myoglobin in a water-based system of not less than 0.003 cm/min., and a rejection rate for albumin in a bovine blood system of not less than 97%. The EVA hollow fiber membrane is useful for hemopurification membranes such as hemodialysis membranes, hemodiafiltration membranes, hemofiltration membranes and continuous hemofiltration membranes, and a process for producing the same.

Abstract: A hydrophilic membrane that includes a hydrophobic polymer and a water-soluble polymer-metal complex is provided. This membrane is made by heating a mixture of a hydrophobic polymer, a metal compound, and a water-soluble polymer. The water-soluble polymer forms complexes with the metal compound and homogeneously entangles with the dissolved hydrophobic polymer to form a viscous dope. The dope is extruded through an annular orifice to form a hollow fiber. The fiber is put in an environment having a controlled humidity so that it becomes partially solidified, and then, the fiber is put in a coagulation bath. The hollow fiber is formed by phase inversion in the coagulation bath and is collected using a take-up wheel that is partially immersed in a leaching bath.

Abstract: The invention concerns a membrane separator for separating out low-colloidal and low-molecular contaminants as well as polyvalent ions (heavy metals) from aqueous media by means of a wound membrane element in which a corrugated distance piece (spacer) is positioned between the layers of the membrane windings. In cross-section the spacer (20, 30) has U-shaped crests (21) and troughs (22) with the legs (26) of the U-forms approximately perpendicular to the membrane surfaces (28), or triangular crests (31) and triangular troughs (32). The spacer (50) can consist of a plastic foil having a corrugated structure on both sides offset by one half-corrugation with respect to each other and where the crests (54, 54′) on both sides make contact with the layers of the membrane windings (4, 6). To increase the turbulence in the flow, the crests (56, 72) can have turbulence elements (60, 76).

Abstract: The present invention relates to polymer membrane meshes having pores with an average diameter from about 10 &mgr;m to about 200 &mgr;m. The membrane meshes are cast from polymer dope mixes that are either homogeneous solutions or stable colloidal dispersions.

Abstract: A method of manufacturing a three dimensional structure. In one embodiment, such structures comprise porous structures suitable for implantation in a host. Such a structure preferably exhibits geometric properties that tend to promote vascularization in the area of the structure when implanted into a host. The method includes selectively applying and exposing layers of biocompatible photoimageable material to create layers forming a cross-linked latticework structure having the desired geometric properties. Each layer is formed on top of a prior layer, preferably before any layer is developed. In one form, the structure is manufactured in connection with an implant device and promotes vascularization that supports bioacceptance/biocompatibility of the implant device.

Abstract: The invention relates to self-supporting capillary membranes which are longitudinally reinforced by continuous reinforcing fibres incorporated in the wall of the capillary membrane, which fibres extend in the longitudinal direction of the capillary membrane. The capillary membranes according to the invention have an improved ultimate tensile strength and a reduced elongation at break as a result of which capillary rupture caused by flow transverse to the capillary membranes occurs considerably fewer times.

Abstract: A pore plugging material, for pH dependent membrane diffusion, in which cyclic olefins having phosphazene-functional moieties provide predictable erosion properties when used to plug pores is separation barriers and other porous membranes. Specific properties of the polymers are dependent on several factors, including molecular weight and identity of side groups attached to the phosphazene moiety. However, as a class, phosphazene-functional cyclic olefins provide both predictable erodibility and uniformly benign hydrolysis products and are, therefore, uniquely suitable as pore plugging polymers for separation barriers and membranes of all kinds. The invention, therefore, embraces the provision of a pH-sensitive erodible pore plugging material to pores in separation barriers and membranes of all kinds.

Abstract: Process for producing hydrophobic polyolefinic membranes for gas exchange via thermally induced liquid-liquid phase separation is disclosed. A solution of at least one polyolefin in a solvent system, of a compound A and a compound B having a viscosity less than 60 mPa s, is extruded to form a shaped object. The compound A is a solvent and compound B preferably a non-solvent of the polymer, and the boiling point of compound A is at least 50° C. higher than that of compound B. After the shaped object leaves the die, at least one surface thereof is subjected to an atmosphere promoting evaporation of compound B, and the shaped object is subsequently cooled until the phase separation and solidification of the high-polymer-content phase take place.

Abstract: The invention relates to the use of water-insoluble, linear polysaccharides as a filtering agent, to a method for producing said filtering agent and to a filtering device. The inventive filtering agent have a high capacity for absorption and retention.

Abstract: A kit for testing male fertility comprises a vessel, a base unit, a liquid supply containing liquid and two filters. The first filter is a sample separation filter which forms a hindrance to transmission of spermatozoa. The second filter of the kit is a spermatozoa detection filter comprising a reagent for identifying spermatozoa. Activation of the kit is prevented until a transport medium, such as the liquid, fills a gap allowing spermatozoa to transmit to a detection zone. The kit may be of one-piece construction and utilizes a thin piece of filter material to separate motile from non-motile spermatozoa.

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: This invention provides a immobilized receptors on supports in liquid chromatographic systems. The method of the invention provides means of evaluating the attachment of agents to receptors comprising the steps of: (a) immobilizing receptors on artificial membrane supports in a column, (b) exposing the supports with the receptors to test agents at varying concentrations in a liquid chromatographic system, (c) eluting the test agent from the column, and (d) evaluating the elution profile of the test materials from the column. Using this method, it is possible to evaluate the interaction of the test agent with the receptor. Following elution, it is possible to directly determine molecular structure by passing the elute through other testing devices such as a mass spectrometer.

Abstract: A device is provided for the sequestration and concentration of polar chemicals from water. The device includes a microporous hydrophilic membrane enclosure formed by a tube or facing membranes.

Abstract: A smooth-textured non-woven, superabsorbent particle-impregnated fibrous structure is disclosed. The web exhibits an improved smooth surface texture. The structure contains from 50% to 80% of ion sensitive SAP having a particle size of less than 200 microns, wood pulp fibers and cellulose acetate fibers, each in preferred specified amounts indicated herein. The superabsorbent, ion sensitive polymer particle-impregnated fibrous structure is made from an aqueous, wet-lay process in which an aqueous furnish comprises solids of fibers and superabsorbent, ion sensitive polymer and dissolved salt, such as preferably, Na2SO4. The furnish is passed over a moving foraminous support, such as a Fourdrinier wire, and a wet web structure is formed, followed by drying.

Abstract: The present invention relates to a process for purifying a liquid hydrocarbon fuel consisting of 5% by weight or less of high molecular weight contaminants, in which the fuel is contacted with a hydrophobic non-porous or nano-filtration membrane and the purified product stream is recovered as the permeate.

Abstract: A membrane and membrane separation process useful in gas, vapor and liquid separations. The membrane comprises a separating layer of a polymer that is characterized by a high glass transition temperature, Tg, such as at least about 100° C., and a high free volume within the polymer material itself, such as a fractional free volume of at least about 0.20. Within the polymer material are dispersed fine non-porous particles, such as silica or carbon black particles, having an average diameter no greater than about 1,000 Å. The membrane is particularly useful for separating C3+ hydrocarbons from other gases.

Abstract: The invention is based on the discovery that certain membranes, which include side chains or molecular “brushes” having, for example, tertiary amino functional groups, can be used as highly effective filters to capture viruses/virus particles from liquids without removal of proteins. New methods based on this discovery include removing viruses from liquids such as blood or plasma, removing viruses from pharmaceuticals, concentrating and/or purifying viruses, e.g., for use in gene therapy, and producing recombinant viruses in new bioreactors. The invention also includes new methods of therapy or adjunct therapy for viral infections, in which a patient's blood or plasma is filtered through the membranes to remove viruses to reduce the viral load. The invention also includes new bioreactors and viral filters containing the membranes.

Abstract: In accordance with the present invention, there are provided articles for use in non-invasive measurements of nitric oxide levels in a variety of fluid media, e.g., in mammalian body fluids. Articles according to the present invention comprise a nitric oxide trapping agent contained within a vessel, wherein the vessel comprises a semi-permeable membrane. Nitric oxide diffuses through the semi-permeable membrane and is trapped therein for subsequent quantitative analysis. Articles of the present invention are particularly useful in selectively detecting nitric oxide in the presence of other NOx species.

Abstract: A porous membrane product is provided which is formed from a porous membrane substrate having its surface completely modified with a perfluorocarbon copolymer composition. The porous membrane product has substantially the same permeability as the porous membrane substrate.

Abstract: A medical apparatus for the extracorporeal treatment of blood or plasma comprises a semi-permeable membrane consisting of at least one electronegative polymer, such that the surface of the semi-permeable membrane has negative electric charges. Before the sterilization of the apparatus, and before or after the formation of the membrane, at least one cationic and anti-protease agent is incorporated in at least one part of the membrane, this agent undergoing bulk adsorption or semi-bulk adsorption in the membrane and/or being bound by an ionic interaction with the electronegative sites of the membrane.

Abstract: A composite membrane (12) comprising a membrane (16) with a structure of nodes (22) connected by fibrils (24). Surfaces of the nodes (22) and fibrils (24) define a plurality of interconnecting pores (26) that extend through the membrane (16) and between major sides (18, 20) of the membrane. The membrane (16) is made from an expanded polytetrafluoroethylene material which tends to tends to absorb oils and certain contaminating agents. The membrane (16) is moisture vapor transmissive, gas permeable and wind and liquid penetration resistant. A coating (28) is disposed on surfaces of the membrane (16) that define the pores (26). The coating (28) is made from an acrylic-based polymer with fluorocarbon side chains. The coating (28) is coalesced on surfaces of the nodes (22) and fibrils (24) to provide oil and certain contaminating agent resistance to the composite membrane (12) without completely blocking the pores (26) in the membrane (16).

Abstract: The invention disclosed is a self-supporting porous ceramic material, which is typically used in ceramic filters as a substrate prior to coating with a thin dense membrane layer of additional ceramic material. Conventional ceramic support structures are not necessarily designed as membrane support substrates. They are typically made with monosized particles and have a uniform cross section. The present support structure is made via a polydisperse slurry method where a functionally gradient structure is achieved by a colloidal destabilization technique. The key for achieving this structure is to colloidally unstable or metastable suspensions of a controlled and broad particle size distribution, so that segregation based on particle diameter will occur during consolidation. This produces a continuously finer mean particle diameter axial profile from one major surface to the other on the cross section of the consolidated structure.

Abstract: The present invention discloses, inter alia, a composition useful for producing a homogeneous, semipermeable membrane, the composition comprising (1) a polysulfone compound, (2) a solvent, such as sulfolane, antypyrine, &dgr;-valerolactam, diethyl phthalate, and mixtures thereof, and (3) a non-solvent, such as poly(ethylene glycol), di(ethylene glycol), tri(ethylene glycol), glycerol, and mixtures thereof. Another aspect of this invention discloses methods for fabricating semipermeable membranes by homogeneously mixing the composition of the polysulfone compound, solvent, and non-solvent, melting the composition, and melt-spinning the molten composition. Another aspect of the present invention includes homogeneous, melt-spun, semipermeable membranes useful for liquid separation processes, such as, but not limited to, microfiltration, ultrafiltration, dialysis, and reverse osmosis.

Abstract: A method for producing an aqueous solution of a polymer having a phosphorylcholine group in which a polymerizable composition containing a polymerizable monomer having the phosphorylcholine group represented by the formula (1) is polymerized in the presence of a non-metal polymerization initiator soluble in a water-containing medium, to obtain a crude polymer aqueous solution, and the crude polymer aqueous solution is purified with a separation membrane, and an aqueous solution of the polymer having the phosphorylcholine group obtained by the method and having not more than 2000 ppm of impurities.

Abstract: A process for the production of a composite membrane constituted by a continuous zeolite layer which is principally located on the surface of a glass support is described. The process comprises, in succession, at least one step in which partial hydrolysis of the silica of the internal and external surfaces of the porous support is carried out, and a zeolite crystallization step. The supported zeolite membranes obtained are advantageously used in continuous separation processes.

Abstract: Described is a semipermeable capillary having a tubular semipermeable wall composed of a membrane-forming material (2) and a tubular strengthening layer (1). The tubular strengthening layer includes an elongated tape having mutually overlapped longitudinal edges. The tubular strengthening layer has an open cohesive structure that is embedded in the membrane-forming material whereby the mutually overlapping longitudinal edges are joined together by the membrane-forming material and a continuous phase is formed between the semipermeable wall and the strengthening layer.