The present invention relates to a composite porous hollow-fiber membrane including a first layer and a second layer which each include a fluororesin-based polymer, in which at least a part of molecular chains of the fluororesin-based polymer is oriented in a longitudinal direction of the composite porous hollow-fiber membrane, the molecular chains of the fluororesin-based polymer have a degree of orientation it in the longitudinal direction of the composite porous hollow-fiber membrane of 0.4 or higher but less than 1.0, the degree of orientation it being calculated with the specific formula.

Disclosed is a block copolymer of the formula: A-B-A (I) or A-B (II), wherein block A is: (i) a polymer of allyl glycidyl ether or (ii) a polymer of allyl glycidyl ether wherein one more of the allyl groups have been replaced with 1,2-dihydroxypropyl group or a group of the formula: —(CH.sub.2).sub.a—S—(CH.sub.2).sub.b—X, wherein a, b, and X are defined herein. The block copolymers find use as wetting agents in the preparation of porous membranes from aromatic hydrophobic polymers such as polyethersulfone. Also disclosed are methods of preparing such block copolymers and porous membranes therefrom.

A method of preparing a membrane comprising the steps of: a) mixing together a membrane-forming polymer, a water-soluble polyetheramine, and a solvent, said mixture containing no component which will react chemically with the polyetheramine; and b) casting said mixture to form the polymer into a solid membrane.

The present invention relates to improved methods for the preparation of thin film composite membranes by interfacial polymerization, preferably (organic) solvent resistant thin film composite membranes. More in particular the method of the present invention allows for the preparation of thin film composite membranes wherein a thin film is deposited on a porous crosslinked support. Said method comprises the one step solidification, impregnation and crosslinking of the porous support through phase inversion by immersion of the cast membrane polymer film in an (aqueous) solvent comprising a polyfunctional monomers.

Membranes having first and second porous portions, wherein the first portion has a more open pore structure than the second portion, wherein the first porous portion includes channels prepared by removing introduced fibers, as well as methods of making and using the membranes, are disclosed.

The present invention relates to a porous membrane suitable for use in high pressure filtration method.

The present invention relates to a porous membrane suitable for use in high pressure filtration method.

An anion exchange membrane is made by mixing 2 trifluoroMethyl Ketone [nominal] (1.12 g, 4.53 mmol), 1 BiPhenyl (0.70 g, 4.53 mmol), methylene chloride (3.0 mL). trifluoromethanesulfonic acid (TFSA) (3.0 mL) to produce a pre-polymer. The pre-polymer is then functionalized to produce an anion exchange polymer. The pre-polymer may be functionalized with trimethylamamine in solution with water. The pre-polymer may be imbibed into a porous scaffold material, such as expanded polytetrafluoroethylene to produce a composite anion exchange membrane.

The present invention provides an intrinsically anti-microbial hollow fiber membrane for filtration of liquids. The membrane comprises a plurality of porous hollow bilayer membrane fibers wherein the liquid enters from outside of the fiber, passing through the porous membrane into the lumen of the fiber and coming out from the hollow ending of the fiber, wherein this configuration provides a liquid outside-in arrangement and retains the filtrate outside. It means that membrane of the invention has built in characteristics to act against microbes in order to provide the use with a safe liquid free from microbes. The outer side or outer wall of the hollow fibers may be configured to become hydrophobic whereas inner side or inner wall of the hollow fiber membrane may be configured to become hydrophilic to enhance the water permeability to a great extent. The hollow fiber membrane may be configured to give it an intrinsic anti-microbial capability. A device containing above said membrane has also been disclosed.

The disclosed technology relates to hollow fiber membranes prepared from a dope solution containing a polymer of vinyl chloride, such as chlorinated polyvinyl chloride, and a thermoplastic polyurethane.