A hollow fiber membrane of the present invention is a hollow fiber membrane having an outer surface and an inner surface, wherein the inner surface has a zebra stripe pattern in which dense portions and porous portions are alternately formed in the longitudinal direction, and the outer surface has a maximum pore size of about 1 μm or less (≤about 1 μm), and wherein the hollow fiber membrane has a water permeability (flux) of ≥about 1,300 LMH/bar to ≤about 5,000 LMH/bar.

There is provided a production method for a resist composition purified product, which includes a step (i) of filtering a resist composition with a filter having a porous structure in which adjacent spherical cells are connected to each other. The filter includes a porous membrane containing at least one resin selected from the group consisting of polyimide and polyamide imide. The resist composition contains a base material component (A) that exhibits changed solubility in a developing solution under action of acid, an onium salt, and an organic solvent component (S), where the content of the organic solvent component (S) is 97% by mass or more.

This invention allows for the production of high strength and high permeability TIPS membranes using extractable fillers with fine powder PVDF grades.

The present invention provides a porous membrane for water treatment, comprising: a high molecular weight polyethylene, a water-soluble polymer and an antioxidant, the high molecular weight polyethylene having an average molecular weight of 1.0×10.sup.5 to 10.0×10.sup.6 and a density of 0.940 to 0.976 g/cm.sup.3; wherein, the weight of the water-soluble polymer is 5 to 50 parts, the weight of the antioxidant is 0.1 to 10 parts, based on 100 parts of the weight of the high molecular weight polyethylene. The porous membrane for water treatment prepared by the present invention has a thickness of 5 to 30 μm, a pore size of 10 to 100 nm, a porosity of 20 to 60%, and a surface contact angle of 30° to 95°. The porous membrane according to the present invention has good durability, simple preparation process, and relatively thin thickness, a uniform pore size distribution and small pore size, good hydrophilicity, as well as good filtration and adsorption effect.

Thin film composite membrane with nano-sized bubbles having enhanced membrane permeability, preparation methods and uses thereof are provided. The method of preparation of a thin film composite membrane, comprising: a) an aqueous solution containing at least an amine, and b) an organic solution containing at least a polyfunctional acyl halide, an additive or soluble gas being present in a) and/or b), or a nano-bubble generator or ultrasound are used to generate nano-bubbles in a) and/or b). Interfacial polymerization of a) and b) occurs at or near the surface of a porous support membrane. The advantage of creating nano-sized bubbles in the separating layer of membrane is that it can reduce membrane resistance without sacrificing the mechanical strength and stability of the membrane so as to improve its water permeability, salt rejection and antifouling. In addition, the process is simple to adopt while performance improvement of the membrane is remarkable.

A porous membrane containing a hydrophobic polymer and a water-insoluble hydrophilic polymer, the porous membrane having a dense layer in the downstream portion of filtration in the membrane, having a gradient asymmetric structure in which the average pore diameter of fine pores increases from the downstream portion of filtration toward the upstream portion of filtration, and having a gradient index of the average pore diameter from the dense layer to the coarse layer of 0.5 to 12.0.

A method is described for forming a body having at least one through-going passage, said method has the steps of: a) providing a mixture comprising particles and at least one liquid pocket inside a curable matrix, b) subjecting said mixture to a first alternating voltage having a first frequency to form a body in which said at least one liquid pocket extends from a first surface of said body to a second surface of said body thereby forming at least one through-going passage lacking curable matrix, and c) curing said curable matrix into a cured matrix, wherein at least some of said particles are located at an interface between said at least one through-going passage comprising liquid and said cured matrix.

Provided is a method including the steps of producing a melt-kneaded product and discharging the melt-kneaded product. In the step of producing a melt-kneaded product, a thermoplastic resin, a non-solvent and an inorganic compound are mixed and melt-kneaded, wherein the non-solvent does not uniformly dissolve the thermoplastic resin of one-quarter mass at a boiling point or 250° C., whichever is lower.

The invention provides polymer-grafted and functionalized nonwoven membranes adapted for use in bioseparation processes, the membranes including a nonwoven web of polyester fibers having an average fiber diameter of less than about 1.5 microns, each of the plurality of polyester fibers having grafted thereon a plurality of polymer segments constructed of a methacrylate polymer, each polymer segment carrying a functional group adapted for binding to a target molecule. The invention also provides a method of bioseparation comprising passing a solution comprising the target molecule, such as a protein, through the nonwoven membrane of the invention such that at least a portion of the target molecule in the solution binds to the nonwoven membrane. A method for preparing a polymer-grafted and functionalized nonwoven membrane adapted for use in bioseparation processes is also provided.

In at least one embodiment, a microporous membrane having a moderate to high water vapor permeability and high liquid water penetration resistance is disclosed. The microporous membrane may be used in building applications, including as or as part of a building wrap, a rain screen, a roofing underlayment, a flashing, a sound proofing material, or an insulation material. The microporous membrane may include at least one thermoplastic polymer, at least one filler, and at least one processing oil. The microporous membrane may be flat or may have ribs. The microporous membrane may include at least one scrim component. A method for forming the microporous membrane is also disclosed.