Hollow fiber membranes having improved toughness and durability are prepared using a vinylidene fluoride polymer-containing component, such as Kynaro resins, having relatively low crystallinity. One aspect of the invention provides a membrane in the form of a fiber, wherein i) the fiber has a porous wall of a polymeric component enclosing a central hollow space extending the length of the fiber, ii) the polymeric component has a crystallinity as determined by wide angle x-ray diffraction of less than about 35%, iii) the polymeric component is comprised of at least one homopolymer or copolymer of vinylidene fluoride and iv) the membrane has an energy to break of at least about 0.5 J per square mm of membrane cross section.

The invention pertains to a polyaryl ether sulfone polymer solution [solution (SP)] comprising: at least one sulfone polymer [polymer (PSI)] having recurring units, wherein more than 50% moles, with respect to all the recurring units of polymer (PSI), are recurring units (R.sub.PSI) selected from the group consisting of those of formulae (R.sub.PSI-1) and (R.sub.PSI-2) herein below: (R.sub.PSI-1) (R.sub.PSI-2) wherein: each of E, equal to or different from each other and at each occurrence, is selected from the group consisting of those of formulae (E-1) to (E-3): (E-I) (E-II) (E-III) each R is independently selected from the group consisting of halogen, alkyl, alkenyl, alkynyl, aryl, ether, thioether, carboxylic acid, ester, amide, imide, alkali or alkaline earth metal sulfonate, alkyl sulfonate, alkali or alkaline earth metal phosphonate, alkyl phosphonate, amine and quaternary ammonium; and j is zero or an integer of 1 to 4; is a bond or a divalent group optionally comprising one or more than one heteroatom; preferably T is selected from the group consisting of a bond, CH.sub.2, C(O), C(CH.sub.3).sub.2, C(CF.sub.3).sub.2, C(?CCI.sub.2), C(CH.sub.3)(CH.sub.2CH.sub.2COOH), and a group of formula: (A) at least one polar organic solvent [solvent (S)]; and at least one mixture of polyhydroxyl aliphatic alcohols having from 1 to 6 carbon atoms or derivatives thereof [mixture (PHA)], said mixture (PHA) comprising at least one ethylene glycol compound [compound (EthyGly)] and at least one glycerol compound [compound (Gly)], to its use for manufacturing membranes, and to membranes obtained therefrom.

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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.

The problem addressed by the present invention is to provide a separation membrane with superior permeation performance and separation performance and having few occurrences of defects. The present invention relates to a separation membrane wherein: the separation membrane has a layer (I) with a thickness of 0.5-100 ?m; letting, in a cross-section in the direction of thickness of the layer (I), region a be a region with a depth of 50-150 nm from a surface (surface A), region b a region with a depth of 50-150 nm from the other surface (surface B), and region c a region with a thickness of 100 nm where the depth from both surfaces is the same, the average pore diameter Pa for region a and the average pore diameter Pb for region b are both 0.3-3.0 nm and the average pore diameter Pc for region c is 3.0 nm or less; and the percentage of open area Ha for region a, the percentage of open area Hb for region b, and the percentage of open area Hc for region c satisfy the following equations. 2Hc<Ha 2Hc<Hb

In embodiments of the present disclosure, a CMS hollow fiber membranes may be prepared to have an ultrathin (e.g. 2 microns or less) separation layer. A precursor hollow fiber may be prepared as dual layer fibers having a thin sheath layer and a core layer. During pyrolysis, the sheath layer is transformed into an ultrathin separation layer. Porosity of the core layer substrate is well-maintained during pyrolysis, thereby enabling high permeance of the CMS hollow fiber membrane. Additionally, in some embodiments, the sheath layer of the precursor hollow fibers may be hybridized prior to pyrolysis. By hybridizing the sheath layer prior to pyrolysis, a CMS hollow fiber may having an improved separation factor, including for example increased carbon dioxide/methane selectivity, may be provided.

A polyvinylidene fluoride (PVDF) casting membrane solution is shaped as a flat sheet membrane by thermally induced phase separation (TIPS), the PVDF membrane is defluorinated with an alkaline potassium permanganate solution, and then the carbon chain is extended with glycidyl methacrylate (GMA) as the graft monomer, and finally the nucleophilic substitution is carried out between melamine and GMA to produce a chelating microfiltration membrane for capturing and enriching heavy metals with high flux and high capacity.

The present invention provides a carbon membrane for fluid separation with which a high-pressure fluid can be separated and purified and which has excellent pressure resistance and is less apt to be damaged. The present invention relates to a carbon membrane for fluid separation, including: a core layer which has a co-continuous porous structure; and a skin layer which has substantially no co-continuous porous structure and is formed around the core layer.

The present invention relates to a porous membrane including a polymer including a polyvinylidene fluoride-based resin as a main component, and a branched polyvinylidene fluoride-based resin as the polyvinylidene fluoride-based resin, in which the polymer has a value of a of 0.32 to 0.41 and a value of b of 0.18 to 0.42, each of which is determined by approximation according to the formula 1 below from a radius of gyration <S.sup.2>.sup.1/2 and an absolute molecular weight M.sub.w of the polymer which are measured by GPC-MALS (gel permeation chromatograph equipped with a multi-angle light scattering detector). <S.sup.2>.sup.1/2=bM.sub.w.sup.a (Formula 1).

The present disclosure relates to a separator and a method of manufacturing the separator. The separator includes a porous support and a hydrophilic polymer applied to the surface of the porous support through a solution including the hydrophilic polymer and a solvent, and satisfies the following Equation: 0.015?(C*D)/(A*B)?0.65, where A is a thickness (?m) of the porous support, B is an air permeability (Gurley, seconds/100 ml) of the porous support, C is a porosity (% by volume) of the porous support, and D is a content (% by weight) of the hydrophilic polymer in the solution.

Disclosed is a hollow-fiber membrane blood purification device having an improved antioxidant performance, good water permeation performance and blood compatibility performance, and economic rationality. The present invention provides a hollow-fiber membrane blood purification device including hollow-fiber membranes filled in a vessel, in which the hollow-fiber membranes contain a hydrophobic polymer, a hydrophilic polymer and a fat-soluble vitamin, when a hollow-fiber membrane bundle is divided into five sections in a lengthwise direction and divided sections positioned in endmost portions are defined as body end portions, an amount of the fat-soluble vitamin present in at least one of the body end portions is the largest among amounts of the fat-soluble vitamin present respectively in all the divided sections, and an amount of the fat-soluble vitamin per m.sup.2 of a hollow-fiber membrane inner surface of the at least one body end portion is 20 mg/m.sup.2 or more and 300 mg/m.sup.2 or less.