There are provided a porous composite membrane formed by blending perfluoroalkoxy alkane (PFA) with an organic substance, and a manufacturing method thereof. The porous composite membrane is able to have pores easily formed simply by blending a fluorine-based polymer with an organic substance without additional pore-forming processes such as stretching and heating, and exhibit excellent properties in terms of resistance to high temperatures and strong acids due to the use of the fluorine-based polymer as a base material, so it is available for use in semiconductor wastewater treatment that uses strong acids like HF.

A method for removing retroviruses from liquid samples and a nanofiber containing liquid filtration medium that simultaneously exhibits high liquid permeability and high microorganism retention is disclosed. Retroviruses are removed from a liquid by passing the liquid through a porous nanofiber containing filtration medium having a retrovirus LRV greater than about 6, and the nanofiber(s) has a diameter from about 10 nm to about 100 nm. The filtration medium can be in the form of a fibrous electrospun polymeric nanofiber liquid filtration medium mat.

Microporous material having a spherulitic matrix made from ethylene chlorotrifluoroethylene copolymer has a plurality of pores having an average pore size greater than about 0.01 micrometer. The material is made by thermally induced phase separation (TIPS) process that includes melt mixing ethylene chlorotrifluoroethylene copolymer, diluent and nucleating agent to provide a melt mixed composition; shaping the melt mixed composition; cooling the shaped melt mixed composition to induce phase separation of the ethylene chlorotrifluoroethylene copolymer to provide a phase separated material; and stretching the phase separated material to provide the microporous material. The microporous material may be incorporated into articles and the articles may include one, two or more layers of microporous material.

Disclosed is a self-wetting porous membrane comprising an aromatic hydrophobic polymer such as polysulfone and a wetting agent comprising a copolymer of formula A-B or A-B-A, wherein A is a hydrophilic segment comprising a polymerized monomer of the formula (I): CH.sub.2?C(R.sup.1)(R.sup.2), wherein R.sup.1 and R.sup.2 are as described herein, and B is polyethersulfone, wherein segments B and A are linked through an oxygen atom. Also disclosed is a method of preparing a self-wetting membrane comprising casting a solution containing an aromatic hydrophobic polymer and the wetting agent, followed by subjecting the cast solution to phase inversion. The self-wetting porous membrane finds use in hemodialysis, microfiltration, and ultrafiltration.

A carbonized PVDC copolymer useful for the separation of an olefin from its corresponding paraffin may be made by heating a polyvinylidene chloride copolymer film or hollow fiber having a thickness of 1 micrometer to 20 micrometers to a pretreatment temperature of 100? C. to 180? C. to form a pretreated polyvinylidene chloride copolymer film and then heating the pretreated polyvinylidene chloride copolymer film to a maximum pyrolysis temperature from 350? C. to 750? C. A process for separating an olefin from its corresponding paraffin in a gas mixture is comprised of flowing the gas mixture through the aforementioned carbonized polyvinylidene chloride (PVDC) copolymer to produce a permeate first stream having an increased concentration of the olefin and a second retentate stream having an increased concentration of its corresponding paraffin.

A homogeneous composite substrate includes a woven cloth and at least one fiber membrane. The woven cloth includes a plurality of first fibers. The fiber membrane is disposed on at least one surface of the woven cloth, and the fiber membrane includes a plurality of second fibers, in which a material of the first fibers and a material of the second fibers are the same, a fiber diameter of each first fiber is larger than or equal to 20 ?m and smaller than or equal to 130 ?m, and a fiber diameter of each second fiber is larger than or equal to 3 ?m and smaller than or equal to 10 ?m.

Described in the present application are methods of producing silane-crosslinked polymer membranes at moderate temperatures using acid catalysts that, in certain embodiments, result in membranes with unexpectedly high permeabilities and selectivities. In certain embodiments, grafting and crosslinking of the silanes occur by immersing a preformed membrane in a solution comprising a silane and an acid catalyst. Alternatively, in certain embodiments, grafting of silanes to a polymer occurs in the presence of acid catalyst in solution and subsequent casting and drying produces crosslinked membranes. In certain embodiments, an acid catalyst is a weak acid catalyst. Also described in the present application are asymmetric crosslinked polymer membranes with porous layers. In certain embodiments, crosslinked cellulose acetate membranes have permeability up to an order of magnitude greater than the permeability of unmodified cellulose acetate membranes. The membranes have porous layers with a high porosity due to their processing in moderate conditions.

A process for separating hydrogen from a gas mixture having hydrogen and a larger gas molecule is comprised of flowing the gas mixture through a carbonized polyvinylidene chloride (PVDC) copolymer membrane having a hydrogen permeance in combination with a hydrogen/methane selectivity, wherein the combination of hydrogen permeance and hydrogen/methane selectivity is (i) at least 30 GPU hydrogen permeance and at least 200 hydrogen/methane selectivity or (ii) at least 10 GPU hydrogen permeance and at least 700 hydrogen/methane selectivity. The carbonized PVDC copolymer may be made by heating and restraining a polyvinylidene chloride copolymer film or hollow fiber having a thickness of 1 micrometer to 250 micrometers to a pretreatment temperature of 100? C. to 180? C. to form a pretreated polyvinylidene chloride copolymer film and then heating and restraining the pretreated polyvinylidene chloride copolymer film to a maximum pyrolysis temperature from 350? C. to 750? C.

A method for manufacturing a filter membrane for inhibiting microorganisms includes the following steps: obtaining a nano-zinc precursor and dissolving it into water, adding at least one reducing agent and interfacial agent to the water, thereby reducing zinc ions of the nano-zinc precursor to zinc particles so as to form liquid having nano-zinc particles; respectively placing the liquid having nano-zinc particles and a polymer material into plastic masterbatch process equipment, respectively volatilizing the fluid having nano-zinc particles and polymer material through the plastic masterbatch process equipment, performing air extraction and mixing by the plastic masterbatch process equipment, and adding at least one grafting agent to perform a mixed graft link, allowing the nano-zinc particles and polymer material to be linked together stably so as to form a plastic masterbatch having nano-zinc particles; and making the plastic masterbatch into a filer membrane through film making equipment.

A method for manufacturing an ion exchange membrane is provided. The method for manufacturing an ion exchange membrane, according to one embodiment of the present invention, comprises the step of electrospinning a support fiber producing solution and an ion exchange fiber producing solution respectively to prepare a laminate in which a support fiber mat consisting of a support fiber and an ion exchange fiber mat consisting of an ion exchange fiber are alternatively laminated. According to the present invention, it is possible to simply control factors, such as the thickness, electroconductivity and mechanical strength of the membrane, and the diameter/ratio of a pore, etc. to be suitable for the use of ion exchange membrane during the manufacturing process, to simplify the manufacturing process. As such, the ion exchange membrane manufactured by the method can be utilized as a universal ion exchange membrane which has a large ion exchange capacity, a small electrical resistance, and a small diffusion coefficient as well as excellent mechanical strength and durability.