Disclosed is a composite membrane including a polymeric membrane having an H.sub.2 permeability of 500 Barrer or more at 25 degrees C., and a coating layer deposited on the polymer membrane by oxidative polymerization.

Hydrophilic fluoroplastic substrates and methods of making hydrophilic fluoroplastic substrates from 4-acryloylmorpholine are disclosed.

Solvent and acid stable ultrafiltration and nanofiltration membranes including a non-cross-linked base polymer having reactive pendant moieties, the base polymer being modified by forming a cross-linked skin onto a surface thereof, the skin being formed by a cross-linking reaction of reactive pendant moieties on the surface with an oligomer or another polymer as well as methods of manufacture and use thereof, including, inter alia separating metal ions from liquid process streams.

The disclosure describes a porous membrane including the following: at least one polymeric feature on a surface of a porous membrane wherein the at least one polymeric features are bonded to the membrane using a nanoscale injecting molding device. Another aspect of the disclosure includes a porous membrane including the following: a first film layer; a second film layer; at least one polymeric feature between the first film layer and second film layer, wherein the at least one polymeric feature is bonded to at least the first film layer.

Hydrophilic fluoroplastic substrates and methods of making hydrophilic fluoroplastic substrates from 4-acryloylmorpholine are disclosed.

A method for creating a seawater desalination reverse osmosis membrane that excels in both water flux and boron removal. The method utilizes the abundant and reactive amino groups of carbon nitride in an interfacial polymerization reaction to enhance the membrane's structure. The unique pore and interlayer structure of carbon nitride is employed to modify the membrane's hydrophilicity, roughness, and interlayer structure, thereby boosting its water flux and boron removal capabilities. Additionally, the carbon nitride solution demonstrates exceptional dispersion properties. Its hydrophilic amino groups react with the organic phase monomer trimesoyl chloride during polymerization, ensuring an even distribution in the polyamide layer without any agglomeration. The evenly dispersed m-phenylenediamine and carbon nitride solution, along with sodium hydroxide in the aqueous phase, quicken the acylation reaction rate. This not only ensures more uniform participation of carbon nitride in the reaction but also further enhances the membrane's water flux and boron removal efficiency.

A method for preparing a polygraphene membrane includes adding graphite and sodium nitrate into sulfuric acid to form a first mixture; adding potassium permanganate solution into the first mixture to form a second mixture; adding hydrogen peroxide solution to the second mixture to form a mixture including soluble manganese ions; filtering the mixture including soluble manganese ions to form an aqueous suspension; centrifuging the aqueous suspension; performing ultrasonication of the suspension to obtain graphene oxide sheets; acylating the graphene oxide sheets to prepare an acylated graphene oxide sheet; and polymerizing the acylated graphene oxide sheets to prepare polygraphene.

The disclosure describes a porous membrane including the following: at least one polymeric feature on a surface of a porous membrane wherein the at least one polymeric features are bonded to the membrane using a nanoscale injecting molding device. Another aspect of the disclosure includes a porous membrane including the following: a first film layer; a second film layer; at least one polymeric feature between the first film layer and second film layer, wherein the at least one polymeric feature is bonded to at least the first film layer.

The present invention belongs to the technical field of membrane-based water treatment and relates to a novel guanidine-based composite nanofiltration (NF) flat-sheet membrane, and a preparation method and application thereof. The present invention provides a method for preparing a guanidine-based composite NF flat-sheet membrane, where a dense separation layer is formed on the surface of a polyethersulfone ultrafiltration membrane through polymerization reaction between the amino group of 1,3-diaminoguanidine and the acyl chloride group of trimesoyl chloride. Under suitable reaction conditions, the guanidine-based composite NF membrane obtained according to the present invention enables effective separation of multivalent ions over a wide pH range, with a rejection rate of over 96% for 1000 ppm of MgSO.sub.4 solution, and can operate continuously and stably in a mixed ions solution with a wide pH.

The present invention provides a composite membrane suitable for liquid-liquid filtration/reverse osmosis. The invention also provides a copolymer useful in the composite membrane, the copolymer comprising an anchoring repeating unit and a foulant-repelling repeating unit, as well as methods for preparing the composite membrane and copolymers. In a preferred embodiment, a copolymer (P [SBMA-co-HEMA]) is synthesized via the free radical copolymerization of a zwitterionic monomer of sulfobetaine methacrylate (SBMA) and an anchoring monomer of hydroxyl ethyl methacrylate (HEMA).