A polymerizable composition for forming an ion-exchange resin precursor, the polymerizable composition containing a monomer component and polyethylene particles in an amount of 50 to 120 parts by mass per 100 parts by mass of the monomer component, wherein the monomer component contains an aromatic monomer for introducing ion-exchange groups and a nitrogen-containing aliphatic monomer, the nitrogen-containing aliphatic monomer being present in an amount of 10 to 35% by mass in said monomer component. An ion-exchange membrane is produced by applying the polymerizable composition onto a polyolefin type filament base material and polymerizing the polymerizable composition to form an ion-exchange resin precursor and, thereafter, introducing ion-exchange groups into the precursor.

A polyolefin microporous film having a laminated structure provided with at least one layer A containing a polyolefin and at least one layer B containing a polyolefin. 0 mass % to less than 3 mass % of polypropylene is contained in layer A and 1 mass % to less than 30 mass % of polypropylene is contained in layer B. When the proportion of polypropylene contained in layer A is represented by PPA (mass %) and the proportion of polypropylene contained in layer B is represented by PPB (mass %), PPB>PPA. In the polyolefin microporous film, the heat shrinkage ratio in TD at 120° C. measured upon applying, in MD, a constant load determined on the basis of the relationship: load (gf)=0.01×piercing strength (gf) of polyolefin microporous film×length (mm) in TD of polyolefin microporous film, is 10 to 40% inclusive.

A polyolefin microporous film having a laminated structure provided with at least one layer A containing a polyolefin and at least one layer B containing a polyolefin. 0 mass % to less than 3 mass % of polypropylene is contained in layer A and 1 mass % to less than 30 mass % of polypropylene is contained in layer B. When the proportion of polypropylene contained in layer A is represented by PPA (mass %) and the proportion of polypropylene contained in layer B is represented by PPB (mass %), PPB>PPA. In the polyolefin microporous film, the heat shrinkage ratio in TD at 120° C. measured upon applying, in MD, a constant load determined on the basis of the relationship: load (gf)=0.01×piercing strength (gf) of polyolefin microporous film×length (mm) in TD of polyolefin microporous film, is 10 to 40% inclusive.

This ionic liquid-containing laminate includes a porous layer having affinity with ionic liquids (C), said layer holding an ionic liquid-containing liquid (A) within voids therein, and a porous layer lacking affinity with ionic liquids (B). The porous layer having affinity with ionic liquids (C) may include an inorganic material (e.g., metal oxide particles having an average particle size of 0.001 to 10 μm on a number basis). The ionic liquid-containing liquid (A) may include an ionic liquid containing cations selected from ammonium, imidazolium and phosphonium cations, and anions selected from fluorine-containing anions, cyano-containing anions and amino acid-derived anions. The porous layer having affinity with ionic liquids (C) may include 1 to 100 volume parts of the ionic liquid-containing liquid (A) with respect to 100 volume parts of voids therein. The ionic liquid-containing laminate is easily formable, and is able to stably hold (or fix) the ionic liquid while maintaining said liquid in a liquid state.

This application is directed to new and/or improved MD and/or TD stretched and optionally calendered membranes, separators, base films, microporous membranes, battery separators including said separator, base film or membrane, batteries including said separator, and/or methods for making and/or using such membranes, separators, base films, microporous membranes, battery separators and/or batteries. For example, new and/or improved methods for making microporous membranes, and battery separators including the same, that have a better balance of desirable properties than prior microporous membranes and battery separators. The methods disclosed herein comprise the following steps: 1.) obtaining a non-porous membrane precursor; 2.) forming a porous biaxially-stretched membrane precursor from the non-porous membrane precursor; 3.) performing at least one of (a) calendering, (b) an additional machine direction (MD) stretching, (c) an additional transverse direction (TD) stretching, and (d) a pore-filling on the porous biaxially stretched precursor to form the final microporous membrane. The microporous membranes or battery separators described herein may have the following desirable balance of properties, prior to application of any coating: a TD tensile strength greater than 200 or 250 kg/cm.sup.2, a puncture strength greater than 200, 250, 300, or 400 gf, and a JIS Gurley greater than 20 or 50 s.

This application is directed to new and/or improved MD and/or TD stretched and optionally calendered membranes, separators, base films, microporous membranes, battery separators including said separator, base film or membrane, batteries including said separator, and/or methods for making and/or using such membranes, separators, base films, microporous membranes, battery separators and/or batteries. For example, new and/or improved methods for making microporous membranes, and battery separators including the same, that have a better balance of desirable properties than prior microporous membranes and battery separators. The methods disclosed herein comprise the following steps: 1.) obtaining a non-porous membrane precursor; 2.) forming a porous biaxially-stretched membrane precursor from the non-porous membrane precursor; 3.) performing at least one of (a) calendering, (b) an additional machine direction (MD) stretching, (c) an additional transverse direction (TD) stretching, and (d) a pore-filling on the porous biaxially stretched precursor to form the final microporous membrane. The microporous membranes or battery separators described herein may have the following desirable balance of properties, prior to application of any coating: a TD tensile strength greater than 200 or 250 kg/cm.sup.2, a puncture strength greater than 200, 250, 300, or 400 gf, and a JIS Gurley greater than 20 or 50 s.

Multi-block isoporous structures for non-aqueous and/or harsh chemical media having at least one of high separation specificity, chemical resistance, and antifouling properties, methods of manufacturing and use, for replacements or alternatives to existing separation membrane technologies.

A water filtration membrane is provided, capable of removing heavy metal ions, filtering out particulates, filtering out bacteria, as well as removing herbicides and volatile organic compounds (VOCs) from water. The membrane is composed of a mat of randomly oriented nanoparticle-coated nanofibers. The nanofibers are covalently bonded to a plurality of substantially uniformly-distributed ceramic nanoparticles embedded in or adhered on the surface of the polymer nanofibers through reactive functional groups. The ceramic nanoparticles have a pattern of deep grooves formed on the nanoparticle surfaces. The bonding of the nanoparticles to the nanofibers is sufficient to retain the nanoparticles on the nanofiber surfaces when water flows through the water filtration membrane. The diameter of the nanofibers is 50-200 nm. The size of the nanoparticles is <40 nm, with a zeta potential of −40 to −45 mV in a dispersion medium. The nanoparticle deep grooves have an average size of approximately 1.2 nm or less.

A water filtration membrane is provided, capable of removing heavy metal ions, filtering out particulates, filtering out bacteria, as well as removing herbicides and volatile organic compounds (VOCs) from water. The membrane is composed of a mat of randomly oriented nanoparticle-coated nanofibers. The nanofibers are covalently bonded to a plurality of substantially uniformly-distributed ceramic nanoparticles embedded in or adhered on the surface of the polymer nanofibers through reactive functional groups. The ceramic nanoparticles have a pattern of deep grooves formed on the nanoparticle surfaces. The bonding of the nanoparticles to the nanofibers is sufficient to retain the nanoparticles on the nanofiber surfaces when water flows through the water filtration membrane. The diameter of the nanofibers is 50-200 nm. The size of the nanoparticles is <40 nm, with a zeta potential of −40 to −45 mV in a dispersion medium. The nanoparticle deep grooves have an average size of approximately 1.2 nm or less.

The present invention relates, in general terms, to a composite membrane for use in filtration. The present invention also relates to a method of fabricating the composite membrane, and a method of filtrating using the composite membrane as disclosed herein. The method of fabricating a composite membrane comprising contacting a perfluorinated polymer solution with a surface of a polymer layer and drying the perfluorinated polymer solution at a relative humidity of less than 20% to form a perfluorinated polymer layer physisorbed on the surface of the polymer layer.