Composite semipermeable membrane

Patent metadata

Field	Value
Publication number	US-2017368510-A1
Application number	US-201515539347-A
Country	US
Kind code	A1
Filing date	Dec 25, 2015
Priority date	Dec 26, 2014
Publication date	Dec 28, 2017
Grant date	—

Abstract

The present invention relates to a composite semipermeable membrane including a supporting membrane and a separation functional layer disposed on the supporting membrane, in which the separation functional layer comprises an aromatic polyamide, the aromatic polyamide has side chains and terminal groups, at least one of the side chains and terminal groups of the aromatic polyamide being an amino group, at least one of the side chains and terminal groups of the aromatic polyamide is a substituent having a structure represented by formula (1): —NXY or formula (2): —NXYZ, and in the aromatic polyamide, a content A of substituents having structures represented by formula (1) and formula (2) and a content B of amide groups satisfy 0.005≦A/B≦0.15.

First claim

1 . A composite semipermeable membrane comprising a supporting membrane and a separation functional layer disposed on the supporting membrane,
wherein the separation functional layer comprises an aromatic polyamide, the aromatic polyamide has side chains and terminal groups, at least one of the side chains and terminal groups of the aromatic polyamide being an amino group, at least one of the side chains and terminal groups of the aromatic polyamide is a substituent having a structure represented by formula (1): —NXY or formula (2): —NXYZ, and in the aromatic polyamide, a content A of substituents having structures represented by formula (1) and formula (2) and a content B of amide groups satisfy 0.005≦A/B≦0.15, provided that, in formula (1) and formula (2), N is a nitrogen atom, and at least one selected from X, Y, and Z is any of O, OH, a benzenesulfonyl group, a methanesulfonyl group, a p-toluenesulfonyl group and an o-nitrobenzenesulfonyl group, the remainder of the X, Y, and Z being a hydrogen atom.

2 . The composite semipermeable membrane according to claim 1 , wherein the aromatic polyamide is formed by interfacial polycondensation of a polyfunctional aromatic amine with a polyfunctional carboxylic acid derivative, and
in the aromatic polyamide, the content A of the substituents having structures represented by formula (1) and formula (2), the content B of amide groups, a content C of terminal carboxyl groups, and a content D of terminal amino groups satisfy 1.3≦B/(A+C+D).

3 . The composite semipermeable membrane according to claim 1 , wherein the substituents having structures represented by formula (1) and formula (2) are each any of a nitro group, a nitroso group, and a hydroxylamino group.

4 . The composite semipermeable membrane according to claim 1 , wherein the aromatic polyamide has a partial structure represented by the following formula (3):

in which Ar 1 is an aromatic ring having 6-14 carbon atoms and having at least one substituent which satisfies Hammett's substituent constants σ m ≧0.40 and σ p ≧0.50, and R 1 and R 2 are each a hydrogen atom or an organic chain having 1-10 carbon atoms.

5 . The composite semipermeable membrane according to claim 4 , wherein the aromatic polyamide has a partial structure represented by the following formula (4):

in which Ar 2 is an aromatic ring having 6-14 carbon atoms and having at least one substituent which is not a hydrogen atom and satisfies Hammett's substituent constants σ m ≦0.15 and σ p ≦0.15, and R 3 and R 4 are each a hydrogen atom or an organic chain having 1-10 carbon atoms.

6 . The composite semipermeable membrane according to claim 4 , wherein the substituent possessed by the partial structure represented by formula (3) is a substituent capable of being converted from a substituent satisfying Hammett's substituent constants σ m ≦0.15 and σ p ≦0.15, by an oxidation reaction.

7 . The composite semipermeable membrane according to claim 1 , wherein the separation functional layer comprising the aromatic polyamide has a protuberance structure, the protuberance structure has protrusions, and a median value of heights of the protrusions is 50 nm or larger.

Assignees

• Toray Industries

Inventors

• Tanaka Hiroaki
• Sato Kazuki
• Ogawa Takafumi
• Sasaki Takao

Classifications

• B01D69/10

  Supported membranes; Membrane supports · CPC title

• B01D2325/30

  Chemical resistance · CPC title

• B01D71/56 Primary

  Polyamides, e.g. polyester-amides · CPC title

• C08G69/26

  derived from polyamines and polycarboxylic acids · CPC title

• C08G69/46

  Post-polymerisation treatment · CPC title