A method providing direct access to porous three-dimensionally (3D) continuous polymer network structures and shapes by combining BCP-resol co-assembly with CO.sub.2 laser-induced transient heating. The CO2 laser source transiently heats the BCP-directed resol hybrid films to high temperatures at the beam position, inducing locally controlled resol thermopolymerization and BCP decomposition in ambient conditions. This enables shaping of BCP-directed porous resin structures with tunable 3D interconnected pores in a single process. Pore size can be varied from 10 nm to about 600 nm.

A polyolefin multilayer microporous membrane is disclosed. The polyolefin multilayer microporous membrane has at least three layers, the membrane comprising a first microporous layer composed of a polyethylene resin containing an ultrahigh molecular weight polyethylene (surface layers) and a second microporous layer composed of a polyolefin rein containing a high-density polyethylene and polypropylene (intermediate layer), wherein (I) the pin puncture strength is at least 25 g/m, (II) the coefficient of static friction with respect to a metal foil is at least 0.40, and (III) the meltdown temperature is at least 180 C.

The present invention is directed to methods of treating a hydrocarbon-containing waste stream to form a hydrocarbon-containing retentate and an aqueous permeate which is substantially free of hydrocarbon. The method includes passing the hydrocarbon-containing waste stream through a microporous membrane to yield the hydrocarbon-containing retentate and the aqueous permeate. The membrane comprises a substantially hydrophobic, polymeric matrix and substantially hydrophilic, finely divided, particulate filler distributed throughout the matrix. The polymeric matrix has pores with a volume average diameter less than 1.0 micron, and at least 50 percent of the pores have a mean diameter of less than 0.35 micron.

In a method for manufacturing a polyolefin microporous film, non-uniformity in a film resulting from non-uniform drying during solvent extraction is minimized, high-speed drying and high-speed continuous productivity of the polyolefin microporous film are implemented. In the method for manufacturing a polyolefin microporous film, in which a composition composed of a polyolefin resin and a plasticizer is made into a film form using extrusion, the plasticizer is extracted and removed using a solvent, and the film is thereafter dried. After the foregoing extraction and before the drying, the film is brought into close contact with a roll, or its width is mechanically restrained. A liquid (heating medium) having a temperature greater than or equal to the boiling point of the solvent is made to contact the film while the film is in close contact with the roll or while the width is restrained, whereby the film is heated and dried.

Composite membranes comprising a layer having first and second microporous surfaces and a bulk between the surfaces, the bulk comprising a first set of pores having outer rims, and a second set of pores connecting the rims, and a polymer matrix supporting the first set of pores; and, a second layer having first and second porous surfaces and a second bulk between the porous surfaces, wherein the second bulk comprises a fibrous matrix; or, first and second microporous surfaces and a second bulk between the microporous surfaces, the second bulk comprising: a third set of pores having outer rims and a fourth set of pores connecting the rims, and a polymer matrix supporting the third set of pores; a third set of pores prepared by phase inversion; or, a fibrous matrix; or, a third set of pores prepared by stretching, track etching or e-beam, are disclosed.

A filtration filter used for filtering a liquid chemical for lithography, provided with a polyimide resin porous membrane; a filtration method including allowing a liquid chemical for lithography to pass through the filtration filter; and a production method of a purified liquid chemical product for lithography, including filtering a liquid chemical for lithography by the filtration method.

A polyphenylene sulfide porous body has, on its surface, porous areas having porous structures, and non-porous areas having substantially no porous structures. Provided is a polyphenylene sulfide porous body that has heat resistance and chemical resistance and overcomes the trade-off between mechanical characteristics and permeation performance.

A method for producing a porous polyimide film comprises: forming a first un-burned composite film wherein the first film is formed on a substrate using a first varnish that contains (A1) a polyamide acid or a polyimide and (B1) fine particles at a volume ratio (A1):(B1) of from 19:81 to 45:65; forming a second un-burned composite film wherein the second film is formed on the first film using a second varnish that contains (A2) a polyamide acid or a polyimide and (B2) fine particles at a volume ratio (A2):(B2) of from 20:80 to 50:50 and has a lower fine particle content ratio than the first varnish; burning wherein an un-burned composite film composed of the first film and the second film is burned, thereby obtaining a polyimide-fine particle composite film; and a fine particle removal step wherein the fine particles are removed from the polyimide-fine particle composite film.

Disclosed is a charged hollow fiber membrane having hexagonal voids for use in high throughput applications. The membrane includes: (i) an inner surface; (ii) an outer surface; (iii) a porous bulk disposed therebetween, wherein the porous bulk comprises at least a first region including: a) a first set of pores having a controlled pore size and having outer rims; b) a second set of pores connecting the outer rims of the first set of pores, wherein the pore size of the first set of pores is greater than the pore size of the second set of pores; and c) a polymer matrix supporting the first set of pores; and (iv) at least one charged zone disposed on the inner surface, on the outer surface, and/or in the porous bulk hollow fiber membrane. Also disclosed is a method for preparing such hollow fiber membranes, which involves coating a filament with a coating composition that includes a membrane-forming polymer, a charged polymer, and dissolvable nanoparticles, followed by phase invention, dissolving of the nanoparticles, and removal of the filament.

The present invention is directed to methods of separating a fluid emulsion stream into a hydrocarbon stream and an aqueous stream, by contacting the stream with a microporous membrane to yield a hydrocarbon product stream and an aqueous product stream. The membrane comprises a substantially hydrophobic, polymeric matrix, and substantially hydrophilic, finely divided, particulate, substantially water-insoluble filler distributed throughout the matrix. The polymeric matrix has a mean pore size less than 1.0 micron, and the purities of the product streams are independent of the flux rate of the aqueous product stream and the pore size of the membrane.