A nanostructured composite membrane filter for rapid water purification and methods for preparing the nanostructured composite membrane filter are provided. The nanostructured composite membrane includes a silver layer having a plurality of silver functionalized nanofibers for disinfecting microorganisms of water, and a chemical modified layer having a plurality of chemical modified nanofibers for removing impurities from the water. The plurality of silver functionalized nanofibers includes a plurality of polyvinyl alcohol (PVA) nanofibers coated with polydopamine (PDA) and silver, and each of the plurality of chemical modified nanofibers includes a polymer matrix such as polyvinyl alcohol (PVA) and anionic polyelectrolytes such as poly (sodium styrenesulfonate) (PSSNa) for capturing metal ions of the water.

The present invention relates to a fibre for purification of liquids comprising a matrix of polymer with organosilane impregnated therein and a method for preparing the same. The fibre of the present invention is capable of providing at least 2 log reduction of viruses, bacteria and cysts and flux of 10 to 1000 litre per square meter per hour at 2 psig.

A nanobiocatalytic membrane for a filtration system is provided which includes a filtration membrane and a plurality of nanobiocatalyst nanoparticles associated with the membrane, each of the nanobiocatalyst nanoparticles including a core, a coating at least partially surrounding the core, and a plurality of nanobiocatalysts coupled to the coating. Each of the plurality of nanobiocatalysts includes an antibacterial nanoparticle comprising bismuth, and a quorum quenching agent coupled to the antibacterial nanoparticle. A nanobiocatalyst nanoparticle for use with a water purification system is also provided. A method of forming a nanobiocatalytic membrane for a filtration system and a method of using a nanobiocatalytic membrane in a filtration system are also provided.

The present invention provides an antifouling ability-imparting agent that adheres well to a variety of water treatment membranes such as reverse osmosis membranes and imparts excellent antifouling ability to the water treatment membranes. The present invention relates to an antifouling ability-imparting agent containing a copolymer, the copolymer containing: a structural unit (I) represented by the following formula (1):

##STR00001##

wherein R.sup.1 is a hydrogen atom or a methyl group; R.sup.2 is a direct bond, —CH.sub.2—, —CH.sub.2CH.sub.2—, or —CO—; R.sup.3s are the same as or different from each other and are each a C1-C20 alkylene group; X is —CH.sub.2CH(OH)CH.sub.2(OH) or —CH(—CH.sub.2OH).sub.2; and n is a number of moles of oxyalkylene groups added and is 0 to 100; and a structural unit (II) represented by the following formula (2):

##STR00002##

wherein R.sup.4 is a hydrogen atom or a methyl group; R.sup.5 is a direct bond, —CH.sub.2—, —CH.sub.2CH.sub.2—, or —CO—; R.sup.6s are the same as or different from each other and are each a C1-C20 alkylene group; R.sup.7 is a hydrogen atom or a C1-C20 alkyl group; and m is a number of moles of oxyalkylene groups added and is 1 to 100.

Composite membrane tubing includes a porous scaffold support combined with polyether block amide copolymer. The composite membrane tubing has overlapping “fusion areas” that are an artifact of the manufacturing process. The methods of manufacturing above-mentioned composite membrane tubing have also been addressed. The composite membrane tubing can be reinforced with a structural mesh to further provide rigidity and strength. Composite membrane tubing or generally extruded tubing can be integrated into a multi-tube module for various applications.

The present disclosure relates to a microporous hollow fiber filter membrane having a large inner diameter and a thin wall. The fiber can be used for sterile filtration of liquids or removal of particles from liquids. The disclosure further relates to a method for producing the membrane and a filter device comprising the membrane.

[Problem to be Solved]

Provided is a polyvinylidene fluoride resin-made porous membrane having excellent hydrophilicity, permeability, and fouling resistance and having suppressed elution of vinyl ether copolymer by using a small amount of vinyl ether copolymer.

[Means to Solve the Problem]

The porous membrane according to the invention comprises a polyvinylidene fluoride resin as a matrix material and a vinyl ether copolymer, wherein the vinyl ether copolymer is a copolymer of an oxyethylene group-containing vinyl ether monomer and a hydrocarbon group-containing vinyl ether monomer.

A porous membrane includes a modacrylic copolymer. The modacrylic copolymer includes, with respect to 100 parts by mass of all structural units constituting the modacrylic copolymer, 15 to 85 parts by mass of a structural unit derived from acrylonitrile, 15 to 85 parts by mass of a structural unit derived from at least one halogen-containing monomer selected from the group consisting of vinyl halide and vinylidene halide, and 0 to 10 parts by mass of a structural unit derived from a vinyl monomer having an ionic substituent. The porous membrane can be produced by preparing a modacrylic copolymer solution by dissolving the modacrylic copolymer in a solvent, and bringing the modacrylic copolymer solution into contact with a non-solvent for the modacrylic copolymer such that the modacrylic copolymer solution is solidified.

The invention provides a method of producing multi-walled carbon nanotube blended polyvinylidene fluoride (MWCNTs/PVDF) membranes for membrane distillation (MD) treatment of saline water using non-solvent induced phase separation (NIPS), said method including mixing two solvents with different solubility parameters and the use of a dual coagulation bath system to control the formation of membrane pore structures and enhance surface hydrophobicity whereby blended PVDF membranes are produced for application in MD processes.

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).