Copolymer C comprising polyarylene ether blocks A and polyalkylene oxide blocks PAO, wherein said polyarylene ether blocks A are blocks of at least one partially sulfonated polyarylene ether.

The composite anion exchange membrane includes: a surface layer on a single surface or both surfaces of an anion exchange membrane substrate, in which the above-described surface layer contains a copolymer of a monomer A which is a water-soluble polyfunctional monomer and a monomer B which is a cationic monomer, an anion exchange capacity of the above-described surface layer is 0.05 meq/cm.sup.3 to 0.50 meq/cm.sup.3, and an anion exchange capacity of the above-described anion exchange membrane substrate is 1.0 meq/cm.sup.3 to 5.0 meq/cm.sup.3.

The composite anion exchange membrane includes: a surface layer on a single surface or both surfaces of an anion exchange membrane substrate, in which the above-described surface layer contains a copolymer of a monomer A which is a water-soluble polyfunctional monomer and a monomer B which is a cationic monomer, an anion exchange capacity of the above-described surface layer is 0.05 meq/cm.sup.3 to 0.50 meq/cm.sup.3, and an anion exchange capacity of the above-described anion exchange membrane substrate is 1.0 meq/cm.sup.3 to 5.0 meq/cm.sup.3.

A composite pervaporation laminate incorporates a thin hydrophilic film laminated on a formable macroporous support layer. The method for making the membrane involves solution casting a thin film on a carrier substrate and transferring the said film onto a macroporous support by hot pressing, such as by decal transfer. Ultra-thin defect-free film, such as less than 5 micrometers, are laminated using this method to achieve very high-water transmission rates and very low or zero gas permeation. The membrane can then be formed into a three-dimensional structure by pleating or corrugating to increase the surface area. The membrane can be used as spacers in an ERV application.

The present invention relates to synthetic membranes and use of these synthetic membranes for isolation of volatile organic compounds and purification of water. The synthetic membrane includes a hydrophobic polymer layer located on a polymeric membrane support layer. The invention includes a method of isolating volatile organic compounds with the synthetic membrane by contacting a volatile organic mixture with the hydrophobic polymer layer of the synthetic membrane and removing volatile organic compounds from the polymeric membrane support layer of the synthetic membrane by a process of pervaporation. The invention also includes a method of purifying water with the synthetic membrane by contacting an ionic solution with the hydrophobic polymer layer of the synthetic membrane and removing water from the polymeric membrane support layer of the synthetic membrane by a process of reverse osmosis. The invention also relates to methods of isolating non-polar gases by gas fractionation.

Disclosed herein are ceramic selective membranes and methods of forming the ceramic selective membranes by forming a selective silica ceramic on a porous membrane substrate.

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.

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.

[Problem] To provide a membrane for the forward osmosis method, which keeps a high porosity, reduces concentration polarization by appropriately controlling the pore distribution, achieves both high water permeability and a self-supporting property, and has high chemical durability such that the membrane is applicable to various draw solutions. [Solution] A separation membrane having a structure inclined from an outer surface side to an inner surface side, a ratio between a thickness of a dense layer having a dense polymer density and a thickness of a coarse layer having a coarse polymer density being in a range of 0.25≦(the thickness of the coarse layer)/[(the thickness of the dense layer)+(the thickness of the coarse layer)]≦0.6, when measuring polymer density distribution in a thickness direction of the separation membrane by Raman spectroscopy.

[Problem] To provide a membrane for the forward osmosis method, which keeps a high porosity, reduces concentration polarization by appropriately controlling the pore distribution, achieves both high water permeability and a self-supporting property, and has high chemical durability such that the membrane is applicable to various draw solutions. [Solution] A separation membrane having a structure inclined from an outer surface side to an inner surface side, a ratio between a thickness of a dense layer having a dense polymer density and a thickness of a coarse layer having a coarse polymer density being in a range of 0.25≦(the thickness of the coarse layer)/[(the thickness of the dense layer)+(the thickness of the coarse layer)]≦0.6, when measuring polymer density distribution in a thickness direction of the separation membrane by Raman spectroscopy.