Abstract: A composite membrane comprising a supporting membrane that includes polyphenylene oxide and a separation layer that is disposed on one main surface of the supporting membrane, wherein the polyphenylene oxide is sulfonated on the one main surface of the supporting membrane and the separation layer includes polyvinyl alcohol having an ionic functional group.

Abstract: [Problem] Provided is a semipermeable membrane that achieves chemical resistance (chlorine resistance, acid resistance, alkali resistance), membrane performance, and membrane strength by sulfonating a polyphenylene-based semipermeable membrane base material under specific conditions. [Solution] A polyphenylene-based semipermeable membrane that is composed of a material containing a polyphenylene-based resin, wherein the semipermeable membrane has a first surface of which at least a portion is sulfonated, and wherein, when concentration distribution of elemental sulfur derived from a sulfonic acid group is measured by elemental analysis in a cross section in a thickness direction of the semipermeable membrane, a ratio of a sulfonated layer obtained by the following expression is 50% or less: Ratio of Sulfonated Layer (%)=Sulfonated Layer Thickness/(Sulfonated Layer Thickness+Non-Sulfonated Layer Thickness)×100.

Abstract: A composite membrane comprising a supporting membrane that includes polyphenylene oxide and a separation layer that is disposed on one main surface of the supporting membrane, wherein the poiyphenylene oxide is sulfonated on the one main surface of the supporting membrane and the separation layer includes polyvinyl alcohol having an ionic functional group.

Abstract: A composite separation membrane is disclosed prepared by forming a separation layer on a surface of a porous support membrane, characterized in that the porous support membrane contains 50% by mass or more of polyphenylene ether; that the separation layer is constituted from a first separation layer and a second separation layer; that the first separation layer is formed with a thickness of from 50 nm to 1 ?m on the surface of the porous support membrane and is a sulfonated polyarylene ether copolymer which comprises a repeated structure of a specific hydrophobic segment and a specific hydrophilic segment; and that the second separation layer is formed with a thickness of from 1 nm to less than 50 nm on a surface of the first separation layer and is an alternately-layered product constituted from one or more kinds of ionomers.

Abstract: The present invention provides a composite separation membrane having a separation layer formed of SPAE on the surface of a porous support membrane wherein the porous support membrane and a coat of SPAE are firmly adhered with each other so that separation property and water permeation property continue for a long period. The present invention is a composite separation membrane having a separation layer on the surface of a porous support membrane, characterized in that said porous support membrane contains 50% by mass or more of polyphenylene ether, and that said separation layer is formed of a sulfonated polyarylene ether copolymer constituted from a repeating structure of a specific hydrophobic segment and a specific hydrophilic segment. The composite separation membrane of the present invention is suitable as a liquid treating membrane such as a nanofiltration membrane and a reverse osmosis membrane.

Abstract: A composite separation membrane is disclosed prepared by forming a separation layer on a surface of a porous support membrane, characterized in that the porous support membrane contains 50% by mass or more of polyphenylene ether; that the separation layer is constituted from a first separation layer and a second separation layer; that the first separation layer is formed with a thickness of from 50 nm to 1 ?m on the surface of the porous support membrane and is a sulfonated polyarylene ether copolymer which comprises a repeated structure of a specific hydrophobic segment and a specific hydrophilic segment; and that the second separation layer is formed with a thickness of from 1 nm to less than 50 nm on a surface of the first separation layer and is an alternately-layered product constituted from one or more kinds of ionomers.

Abstract: The present invention provides a composite separation membrane having a separation layer formed of sulfonated polyarylene ether (SPAE) copolymer on a surface of a porous support membrane wherein both high separation property and high water permeation property are achieved. A composite separation membrane wherein a surface of a porous support membrane containing polyphenylene ether is coated with a thin film of a sulfonated polyarylene ether copolymer constituted from a repeating structure of a hydrophobic segment and a hydrophilic segment, characterized in that when proton nuclear magnetic resonance spectrum is measured at ?10° C., chemical shift of a spectral peak top derived from water contained in the membrane satisfies from 4.15 ppm to less than 5.00 ppm.

Abstract: The present invention provides a composite separation membrane having a separation layer formed of SPAE on the surface of a porous support membrane wherein the porous support membrane and a coat of SPAE are firmly adhered with each other so that separation property and water permeation property continue for a long period. The present invention is a composite separation membrane having a separation layer on the surface of a porous support membrane, characterized in that said porous support membrane contains 50% by mass or more of polyphenylene ether, and that said separation layer is formed of a sulfonated polyarylene ether copolymer constituted from a repeating structure of a specific hydrophobic segment and a specific hydrophilic segment. The composite separation membrane of the present invention is suitable as a liquid treating membrane such as a nanofiltration membrane and a reverse osmosis membrane.