This invention relates to certain microporous articles comprising certain PEDEK-PEEK copolymers, to a method for making said microporous articles, in particular to a method of making microporous articles from a blend comprising said PEDEK-PEEK copolymer and at least one additional polymer, comprising processing said blend into a film and treating the film with a solvent for obtaining the microporous article.

Disclosed is a polyvinylidene fluoride/ultra-high molecular weight polyethylene blend microporous membrane and preparation method thereof, which belongs to the field of microporous membrane. The blend microporous membrane has good hydrophobicity, mechanical properties and permeability. The preparation method includes: preparing a suspension by polyvinylidene fluoride, ultra-high molecular weight polyethylene, antioxidant and diluent; then feeding the obtained suspension into a twin-screw extruder, and the cast membrane gel extruded from the outlet is directly injected into a metal mold for injection molding; the mold temperature and the outlet temperature of the extruder are the same, and the cavity surface of the mold has micro-prism array structure; then cooling the mold in aqueous medium to obtain a nascent gel membrane; drying the obtained nascent gel membrane in a freeze dryer after removal of the diluents by extraction. The prepared membrane can be used in the membrane separation technology such as membrane distillation.

A method for producing a microporous material comprising the steps of: providing an ultrahigh molecular weight polyethylene (UHMWPE); providing a filler; providing a processing plasticizer; adding the filler to the UHMWPE in a mixture being in the range of from about 1:9 to about 15:1 filler to UHMWPE by weight; adding the processing plasticizer to the mixture; extruding the mixture to form a sheet from the mixture; calendering the sheet; extracting the processing plasticizer from the sheet to produce a matrix comprising UHMWPE and the filler distributed throughout the matrix; stretching the microporous material in at least one direction to a stretch ratio of at least about 1.5 to produce a stretched microporous matrix; and subsequently calendering the stretched microporous matrix to produce a microporous material which exhibits improved physical and dimensional stability properties over the stretched microporous matrix.

A porous ultra-thin polymer film has a film thickness of 10 nm-1000 nm. A method of producing the porous ultra-thin polymer film includes dissolving two types of mutually-immiscible polymers in a first solvent in an arbitrary proportion to obtain a solution; applying the solution onto a substrate and then removing the first solvent from the solution applied onto the substrate to obtain a phase-separated ultra-thin polymer film that has been phase-separated into a sea-island structure; and immersing the ultra-thin polymer film in a second solvent which is a good solvent for the polymer of the island parts but a poor solvent for a polymer other than the island parts to remove the island parts, thereby obtaining a porous ultra-thin polymer film.

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 m or less (about 1 m), and wherein the hollow fiber membrane has a water permeability (flux) of about 1,300 LMH/bar to about 5,000 LMH/bar.

Provided are a porous film having excellent surface smoothness and a method for producing the same. The surface roughness of a porous film of polyvinylidene fluoride, polyethersulfone, polyimide and/or polyamide-imide is Ra 30,000 or less. The opening diameter of the porous film is preferably from 100 nm to 5000 nm. The method for producing a porous film preferably includes a step for kneading a varnish containing fine particles and at least one resin selected from the group consisting of polyvinylidene fluoride, polyether sulfone, polyamic acid, polyimide, polyamide-imide precursor, and polyamide-imide. The varnish preferably has a viscosity at 25 C. of 0.1-3 Pa.Math.s, a solids fraction concentration of 10-50 mass %, and a fine particle average particle size of 10-5000 nm.

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

A process for preparing a porous membrane containing a thermoplastic polymer, the process containing: (i) forming a film shaped compound containing the thermoplastic polymer and a water soluble polymer; and (ii) extracting the film shaped compound with a solvent mixture, thereby obtaining the porous membrane; wherein the thermoplastic polymer has pores with an average pore diameter <2000 nm, determined using Hg porosimetry according to DIN 66133, the thermoplastic polymer contains a polyurethane, wherein the polyurethane contains: 11 to 79% by weight of a mixture of a diol and a diisocyanate; and 21 to 89% by weight of the compound with two functional groups which are reactive towards isocyanate groups.

A method for preparing a nanoporous membrane includes alternatively repeating, on the surface of a porous substrate, the laminating of a hydrophilic homopolymer and the laminating of an amphiphilic block or graft copolymer to provide a polymer multilayer film in which the alternative laminate of the hydrophilic homopolymer and the amphiphilic block or graft copolymer is formed. The polymer multilayer film is annealed to form a microphase separated polymeric membrane. The laminating of a hydrophilic homopolymer and the laminating of a supramolecular structure compound are alternatively repeated, on the surface of the polymeric membrane, to form the alternative laminate of the hydrophilic homopolymer and the supramolecular structure compound.

The present disclosure describes a method of manufacturing a molded filter body, by which a molded filter body can be produced more easily.

A method of manufacturing a molded filter body having a layer of a filtering material includes: forming a layer of a support mixed with a template, on a surface of the layer of the filtering material; and forming water passage holes in the layer of the support by removing the template.