In summary, the disclosure provides certain membranes useful as filter materials in the removal of metal ions, metal particulates, and/or organic contaminants from liquid compositions, in particular liquid compositions used in the microelectronic device industry. The membranes of the disclosure are porous membranes comprised of poly(quinoline) polymers. Advantageously, the poly(quinoline) membranes are thermally stable and hydrolytically stable and can thus be cleaned between uses using acidic material such as dilute hydrochloric acid, without suffering from significant degradation. The poly(quinoline) polymers can be designed to be soluble in certain solvents, thus enabling the manufacture of the corresponding porous membranes by immersion-casting techniques.

Provided is a water-treatment membrane including a porous support; and a polyamide active layer including chlorine on a surface thereof, wherein CIE L*a*b* color coordinate values after storing for 30 days or longer at 25° C. to 80° C. satisfy Equation 1 to Equation 3:
91<L*<97  <Equation 1>
−1.5<a*<1.5  <Equation 2>
−1.5<b*<8  <Equation 3> of the present disclosure, a water-treatment module including the same, and a method for manufacturing the same.

A polymer film has a loofah-like structure. It has a fibrous framework structure formed by three-dimensional interwoven and interconnected polymer fibers and a three-dimensional interconnected network pore structure distributed in the fibrous framework structure. The polymer is an organic polymer and the fibrous framework structure is integrally formed by the polymer. The film has a volume porosity of from 50% to 95%. The film is obtained by means of a combination method for atomization pretreatment and non-solvent phase separation. The film can be used in the fields of gas filtration, liquid filtration, oil-water separation, adsorption materials, catalysis, pharmaceutical sustained release materials, anti-adhesion coatings, oil delivery and oil spill interception.

The invention relates to the field of industrial wastewater treatment, and particularly discloses a nanofiltration membrane for treating printing and dyeing wastewater and its preparation method. The preparation method comprises the following steps: S1, pouring an aqueous solution containing m-phenylenediamine, camphorsulfonic acid and triethylamine onto the surface of a polysulfone ultrafiltration membrane, setting still for 10 s to 30 s, and then removing the excess aqueous solution from the surface; S2, pouring an organic solution containing trimesoyl chloride and an interface auxiliary polymerization agent onto the surface of the membrane obtained in step S1, reacting for 5 s to 20 s, and then removing the excess solution from the surface; and S3, setting the membrane obtained in step S2 still and then carrying out heat treatment and water rinsing on the membrane in sequence, thus obtaining the nanofiltration membrane.

A method for preparing a nanofiltration membrane and a nanofiltration membrane prepared therefrom, the method comprising the following steps: dissolving a polymer in a solvent to prepare a polymer solution, and curing the polymer solution on a support material to form a base membrane; sequentially applying a first liquid-phase solution and a second liquid-phase solution on the base membrane to form a nascent membrane; densifying the nascent membrane by using a solution that contains an alkaline substance; processing the densified nascent membrane by using a solution that contains an acidic substance; and obtaining the nanofiltration membrane after post-processing and drying.

The present invention provides a porous hollow fiber membrane including a polysulfone-based polymer and a hydrophilic polymer, and having a dense layer in a section from an outer surface portion to a center region of a membrane thickness, a thickness of the dense layer being 10 to 30 μm, and a ratio of a pore having a pore size of more than 50 nm and a ratio of a pore having a pore size of 10 nm or smaller in the dense layer being 25 to 40% and 20% or less, respectively.

There is provided a semi-crystalline polymer membrane, the membrane being a single-layer membrane and su-perwettable without provision of a coating or additives. There is also provided a method of forming the membrane comprising: depositing a solution on a substrate surface, the solution comprising a semi-crystalline polymer to form a nascent membrane; spraying a fluid on the nascent membrane; and immersing the nascent membrane in a non-solvent to form the semi-crystalline polymer membrane. In preferred embodiments, the fluid sprayed on the nascent membrane is selected from compressed air, water, a mixture of ethanol and water, or a solid suspension of ethanol/water/sodium chloride.

The disclosure relates to superhydrophobic membranes and methods of making and using such membranes. Polydimethylsiloxane (PDMS) substrate is formed on sandpaper such that the PDMS substrate has a surface texture replicating the opposite impression of the sandpaper texture. Separately, a PVDF solution is prepared and disposed on the PDMS substrate. The PVDF substrate and liquid film combination are transferred to a solution of deionized water mixed with 2-propanol to form a PVDF film on the PDMS substrate. The PVDF film-PDMS substrate is transferred to a second DI water bath, after which the PVDF film is detached from the PDMS substrate. The PVDF film is then washed and dried, to yield a superhydrophobic PVDF membrane having the texture of sandpaper.

A porous membrane is made from a poly(phenylene ether) copolymer containing 10 to 40 mole percent repeat units derived from 2-methyl-6-phenylphenol and 60 to 90 mole percent repeat units derived from 2,6-dimethylphenol; and a block copolymer containing backbone or pendant blocks of poly(C.sub.2-4 alkylene oxide). The porous membrane is made by dissolving the poly(phenylene ether) copolymer in a water-miscible polar aprotic solvent to form a membrane-forming composition; and phase-inverting the membrane forming-composition in a first non-solvent composition to form the porous membrane. A method of making a hollow fiber by coextrusion through a spinneret having an annulus and a bore, includes coextruding the membrane-forming composition through the annulus, and a first non-solvent composition through the bore, into a second non-solvent composition to form the hollow fiber.

The object of the present invention is to provide a porous membrane by which a useful component can be recovered while suppressing the clogging during filtration of a protein solution and from which only a small amount of an eluate is eluted even when an aqueous solution is filtered.

The present invention provides a porous membrane containing a hydrophobic polymer and a water-insoluble hydrophilic polymer, the porous membrane having a dense layer in the downstream portion of filtration in the membrane, having a gradient asymmetric structure in which the average pore diameter of fine pores increases from the downstream portion of filtration toward the upstream portion of filtration, and having a gradient index of the average pore diameter from the dense layer to the coarse layer of 0.5 to 12.0.