In one aspect, a composite membrane comprises a polymeric host comprising polybenzimidazole or polybenzimidazole derivative and graphene oxide dispersed in the polymeric host, the graphene oxide at least partially functionalized with phosphonic acid moieties, phosphonate moieties or combinations thereof. In some embodiments, the functionalized graphene oxide is homogeneously dispersed in the polymeric host and/or is not agglomerated in the polymeric host.

The present invention provides a separation membrane having excellent separation performance and permeation performance, having high membrane strength, and mainly including a cellulose-based resin. The present invention relates to a separation membrane containing a cellulose ester and having a tensile elasticity of 1,500 to 6,500 MPa.

A solution contains at least one sulfone polymer and N-tert.-butyl-2-pyrrolidone. The solution can be used in a process of making a membrane, which is useful for water treatment.

The purpose of the invention is to provide a porous hollow-fiber membrane containing a regenerated cellulose and having an elastic limit pressure of 200 kPa or more.

The present invention relates to a hollow fiber membrane including, sequentially from the center: a first layer having a high-density sponge structure including pores with a size of 1 nm or less; a second layer including a finger-shaped structure; and a third layer having a low-density sponge structure including pores with a size of 10 to 1,000 m, and to a method for producing the hollow fiber membrane.

Provided is a reverse osmosis membrane comprising: a support layer comprising a support and a polysulfone layer; and an active layer, wherein a compression modulus is from 20 MPa to 40 MPa, to a method for manufacturing the same, and a water-treatment module.

Described is a polyethylene membrane and in particular an ultra-high molecular weight polyethylene member that provides a high air permeability and is hydrophobic. The membranes have small pores and are suitable for sterilization by exposure to gamma radiation. The membranes can be made by methods that involve one or more of stretching the membrane and grafting hydrophobic monomers onto the membrane surface. A perfluorinated monomer, such as perfluoro-n-octyl acrylate, can be grafted to one or more surfaces of the membrane. The membrane have a high flow rate compared to unstretched or ungrafted membranes.

A separation membrane sheet that causes a specific fluid component to selectively permeate therethrough, comprises: a first porous layer; and a resin composition layer formed on the first porous layer. The resin composition layer has a filtration residue fraction of greater than or equal to 20% and less than or equal to 90%; and contains a resin having an ionic group or a salt thereof, and has an ion exchange capacity of greater than or equal to 1 millimole equivalent per 1 g of a dry resin in a filtration residue.

A bendable flexible flat membrane module includes: a membrane facing each other and constituting both outer surfaces; a support member made of a flexible material and embedded inside the membrane constituting the both outer surfaces; and a plurality of point bonding portions formed by pressing and bonding the both outer surfaces facing each other at a predetermined point.

A porous polytetrafluoroethylene membrane (20) of the present disclosure has an average pore diameter of 0.03 to 0.2 m and a porosity of more than 25% and not more than 90%. The number of pores present in a region having a width of 23 m and a thickness of 1 m in a cross-section parallel to the thickness direction is in the range from 40 to 120. The porous polytetrafluoroethylene membrane (20) is made of polytetrafluoroethylene having a number-average molecular weight in the range from 2,000,000 to 12,000,000, and a puncture strength per unit thickness is in the range from 5.0 to 15 gf/m.