A filtration membrane including a first layer comprising a polyester terephthalate nonwoven fabric, a second layer comprising a polyvinylidene fluoride matrix doped with a polyvinylpyrrolidone and titanium dioxide nanoparticles, and a third layer comprising a polypyrrole polymer. A method of making the membrane is also described. The membrane of the present disclosure is self-cleaning under visible light irradiation conditions.

The present invention relates to a method for producing a porous membrane, the method being characterized in that a solvent system comprising 2-pyrrolidone and N-alkyl-2-pyrrolidone is used, wherein the content ratio of 2-pyrrolidone to N-alkyl-2-pyrrolidone in the solvent system is from 90%:10% to 10%:90%, based on mass %, and wherein N-alkyl-2-pyrrolidone is N-propyl-2-pyrrolidone and/or N-butyl-2-pyrrolidone. Furthermore, the present invention relates to a porous membrane obtainable by said method. Moreover, the present invention relates to the use of a specific solvent system for the production of a porous membrane.

Novel PBI films which may be used in electrochemical cells, such as redox flow batteries, are disclosed. Additionally, disclosed herein are membranes which comprise the novel PBI films which may be free from an organic solvent, and have a tensile strength at break of at least 25 MPa after drying.

An ultrafiltration membrane comprising: (i) a first polymer, and (ii) a second, charged polymer wherein the first polymer and second polymer have different hydrophobicities.

This invention provides a polymeric separation membrane that has excellent durable antibacterial effect and stain resistance, and a preparation method thereof. The polymeric separation membrane can be widely applied for water treatment, which belongs to the field of water treatment and membrane separation science and technology. The polymeric separation membrane containing quaternary ammonium salt is prepared by the immersion precipitation phase inversion method, using quaternary ammonium salt mixed with polymer and additives. This modification method effectively improves the antibacterial and antifouling ability of the polymeric separation membrane prolongs the service life of membranes and significantly inhibits the reproduction of bacterial and microbial. The preparation method has the advantages of simple process, easy operation, easy for promotion, and also avoids expensive equipment. The polymeric separation membrane has great antibacterial ability and stain resistance, therefore, it has potential application in the field of water treatment.

A porous asymmetric membrane comprises a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer; and a polymer additive. A separation module can be fabricated from the porous asymmetric membrane. A method of forming the porous asymmetric membrane comprises: dissolving a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer and, a polymer additive in a water-miscible polar aprotic solvent to form a porous asymmetric membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous asymmetric membrane. The polymer additive comprises hydrophilic functional groups, copolymerized hydrophilic monomers, or blocks of hydrophilic monomer repeat units. For example, the polymer additive can comprise a hydrophilic polymer or amphiphilic polymer. The porous asymmetric membrane can be a flat membrane or hollow fiber.

A porous composite membrane includes a porous support layer of a poly(phenylene ether) or poly(phenylene ether) copolymer; and an amphiphilic copolymer having a hydrophobic block and a hydrophilic block or graft, wherein the hydrophobic block includes a polystyrene block, a poly(phenylene ether) block, or a poly(phenylene ether) copolymer block; and an ultrathin, cross-linked, water permeable layer, which is the reaction product of an electrophilic monomer and a nucleophilic monomer, in contact with a side of the porous support layer. The reaction product can be a polyamide that is the interfacial condensation product of: an aromatic, polyfunctional acyl halide comprising of 3 to 6 acyl halide groups per aromatic ring and an aromatic polyamine comprising at least two primary amine groups and a maximum number of primary amine groups that is less than or equal to the number of acyl halide groups on the polyfunctional acyl halide.

A porous asymmetric membrane comprises a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer; and a polymer additive. A separation module can be fabricated from the porous asymmetric membrane. A method of forming the porous asymmetric membrane comprises: dissolving a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer and, a polymer additive in a water-miscible polar aprotic solvent to form a porous asymmetric membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous asymmetric membrane. The polymer additive comprises hydrophilic functional groups, copolymerized hydrophilic monomers, or blocks of hydrophilic monomer repeat units. For example, the polymer additive can comprise a hydrophilic polymer or amphiphilic polymer. The porous asymmetric membrane can be a flat membrane or hollow fiber.

The disclosure provides a solvent resistant polyimide/polyethyleneimine@titanium dioxide nanohybrid ultrafiltration membrane with high solvent permeability and a preparation method thereof. The preparation method comprises the following steps: dissolving a titanium dioxide precursor Ti-BALDH and polyimide into N-methylpyrrolidone to prepare a casting solution, then coating on the non-woven fabric, and preparing the solvent resistant nanohybrid polyimide membrane in one step through a non-solvent induced phase separation-interface crosslinking-in-situ biomimetic mineralization coupling method. According to the disclosure, a solvent resistant polyimide/polyethyleneimine@TiO.sub.2 nanohybrid ultrafiltration membrane (PEIPI@TiO.sub.2) with high solvent permeability prepared through a simple non-solvent induced phase separation-interface chemical crosslinking-in-situ bionic mineralization coupling 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 trimethylamine 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.