An embodiment of the present invention provides a polyolefin microporous membrane, including: a first porous layer containing a polyolefin and having a structure including a first rod-shaped crystal extending in one direction and plural first plate-shaped crystals arranged in a separated state and intersecting the first rod-shaped crystal, and a second porous layer containing a polyolefin and having a structure including a second rod-shaped crystal extending in another direction intersecting the one direction and plural second plate-shaped crystals arranged in a separated state and intersecting the second rod-shaped crystal.

Provided are certain composite membranes useful for removing various impurities from liquids. In certain aspects, the composite membranes comprise a hydrophobic polymer having a polyamide coated thereon, and in other aspects, such composite membranes having certain acrylic polymers coated thereon. The composite membranes are useful in the removal of various impurities in liquids, such as those encountered in industrial and life sciences processes.

Described are ion-exchange membranes that include a porous polymeric membrane and imidazole ion-exchange groups at surfaces of the membrane; ion-exchange membranes and filters that contain the ion-exchange membranes; and methods of using the ion-exchange membranes and filters for separating charged biological molecule from a liquid.

An ion exchange membrane has multiple layers of ionic polymers which each contain substantially different chemical compositions. i.e. varying side chain lengths, varying backbone chemistries or varying ionic functionality. Utilizing completely different chemistries has utility in many applications such as fuel cells where for example, one layer can help reduce fuel crossover through the membrane. Or one layer can impart substantial hydrophobicity to the electrode formulation. Or one layer can selectively diffuse a reactant while excluding others. Also, one chemistry may allow for impartation of significant mechanical properties or chemical resistance to another more ionically conductive ionomer. The ion exchange membrane may include at least two layers with substantially different chemical properties.

The present invention relates to a porous sheet product, to a filter element comprising the porous sheet product, to a method for producing the porous sheet product, to a method for producing the filter element, and to the use of the sheet product and of the filter element.

Composite materials for removing hydrophobic components from a fluid include a porous matrix polymer, carbon nanotubes grafted to surfaces of the porous matrix polymer, and polystyrene chains grafted to the carbon nanotubes. Examples of porous matrix polymer include polyurethanes, polyethylenes, and polypropylenes. Membranes of the composite material may be enclosed within a fluid-permeable pouch to form a fluid treatment apparatus, such that by contacting the apparatus with a fluid mixture containing water and a hydrophobic component, the hydrophobic component absorbs selectively into the membrane. The apparatus may be removed from the fluid mixture and reused after the hydrophobic component is expelled from the membrane. The composite material may be prepared by grafting functionalized carbon nanotubes to a porous matrix polymer to form a polymer-nanotube composite, then polymerizing styrene onto the carbon nanotubes of the polymer-nanotube composite.

Composite materials for removing hydrophobic components from a fluid include a porous matrix polymer, carbon nanotubes grafted to surfaces of the porous matrix polymer, and polystyrene chains grafted to the carbon nanotubes. Examples of porous matrix polymer include polyurethanes, polyethylenes, and polypropylenes. Membranes of the composite material may be enclosed within a fluid-permeable pouch to form a fluid treatment apparatus, such that by contacting the apparatus with a fluid mixture containing water and a hydrophobic component, the hydrophobic component absorbs selectively into the membrane. The apparatus may be removed from the fluid mixture and reused after the hydrophobic component is expelled from the membrane. The composite material may be prepared by grafting functionalized carbon nanotubes to a porous matrix polymer to form a polymer-nanotube composite, then polymerizing styrene onto the carbon nanotubes of the polymer-nanotube composite.

There are provide a cell separation filter with which cells can be separated without damage and can suppress adsorption, a filtering device, and a manufacturing method for a cell separation filter. The cell separation filter is composed of a nonwoven fabric that is formed of fibers containing a water-insoluble polymer and a hydrophilizing agent and has a fiber density difference in the film thickness direction. The nonwoven fabric has an average through-hole diameter of 2.0 μm or more and less than 10.0 μm, a void ratio of 75% or more and 98% or less, a film thickness of 100 μm or more, and a critical wet surface tension of 72 mN/m or more.

In accordance with at least selected embodiments, a battery separator or separator membrane comprises one or more co-extruded multi-microlayer membranes optionally laminated or adhered to another polymer membrane. The separators described herein may provide improved strength, for example, improved puncture strength, particularly at a certain thickness, and may exhibit improved shutdown and/or a reduced propensity to split.

In accordance with at least selected embodiments, a battery separator or separator membrane comprises one or more co-extruded multi-microlayer membranes optionally laminated or adhered to another polymer membrane. The separators described herein may provide improved strength, for example, improved puncture strength, particularly at a certain thickness, and may exhibit improved shutdown and/or a reduced propensity to split.