Toray Industries, Inc.

Jun Okabe

Masahiro Kimura

Koji Nakatsuji

Tsuyoshi Hamada

Masahiro Henmi

Takao Sasaki

Hiroki Tomioka

Takafumi Ogawa

Masaki Higashi

Keisuke Yoneda

Ryoma Miyamoto

The present invention relates to a composite semipermeable membrane including: a supporting membrane including a substrate and a porous supporting layer; and a separation functional layer disposed on the porous supporting layer, in which the separation functional layer includes: a crosslinked polyamide; and a hydrophilic polymer which is a polymer of a monomer having an ethylenically unsaturated group, and a surface of the separation functional layer has a ratio of the number of oxygen atoms to the number of nitrogen atoms (O/N ratio), both determined by X-ray photoelectron spectrometry, of 1.5-10, and a standard deviation of the O/N ratio of 0.15 or larger.

Composite semipermeable membrane and method for producing composite semipermeable membrane

An object of the present invention is to provide a composite semipermeable membrane which has a high permeation rate and high salt removal performance and is excellent in terms of performance stability during long-term operation. The composite semipermeable membrane of the present invention includes: a supporting membrane including a substrate and a porous supporting layer; and a separation functional layer disposed on the porous supporting layer, the separation functional layer includes a crosslinked polyamide and a hydrophilic polymer having an acidic group, and in the separation functional layer, a ratio of (molar equivalent of amino groups)/(molar equivalent of amide groups) is 0.18 or less.

Composite semipermeable membrane and method for producing same

The present invention provides a separation membrane that is usable at a high temperature and a high pressure. The solvent-resistant separation membrane of the present invention has an average pore diameter of the separation membrane surface of 0.005 to 1 &#x3bc;m and includes a portion where a degree of cyclization (I/I) as measured by the total reflection infrared absorption spectroscopy is 0.5 to 50.

Solvent-resistant separation membrane

Provided is a composite semipermeable membrane having a high salt removal rate and a high water permeability. The composite semipermeable membrane comprises a substrate, a porous support layer formed on the substrate, and a separation functional layer formed on the porous support layer, the hydrophilic macromolecule concentration on the substrate-side surface of the porous support layer being higher than that on the separation functional layer-side surface.

Composite semipermeable membrane

An object of the present invention is to provide a composite semipermeable membrane which has excellent chemical resistance, separation performance, and water permeability, and the composite semipermeable membrane has the following structure. The present invention provides a composite semipermeable membrane in which an separation function layer is formed on a microporous supporting membrane, wherein the separation function layer is formed from (A) a silicon compound in which a reactive group having an ethylenically unsaturated group and a hydrolyzable group are directly bonded to silicon atoms, and (B) a compound having an ethylenically unsaturated group other than the silicon compound, by condensation of the hydrolyzable group of the silicon compound (A) and polymerization of the ethylenically unsaturated group of the silicon compound (A) and the ethylenically unsaturated group of the compound (B) having the ethylenically unsaturated group.

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Otsu, Japan

Jun Okabe