Toray Industries, Inc.

Takaaki Yasuda

Masayuki Hanakawa

Kenta Iwai

Toshiyuki Ishizaki

Harutoki Shimura

Shinya Mitsui

Masahiro Kimura

Tamotsu Kitade

Shun Shimura

Takafumi Ogawa

Yohei Adachi

A composite semipermeable membrane, including: a microporous support layer; and a separation functional layer provided on the microporous support layer, in which the separation functional layer includes a crosslinked wholly aromatic polyamide which is a polycondensation product of a polyfunctional aromatic amine and a polyfunctional aromatic acid chloride and contains amino groups and carboxyl groups, and in positive secondary ions measured on a surface of the separation functional layer by time-of-flight secondary ion mass spectrometry, when (count number of m/z=104.03)/(count number of m/z=108.06) is denoted by a, and a molar ratio (carboxyl group/amino group) of the carboxyl group to the amino group, which is obtained by analyzing the entire separation functional layer byC solid state NMR, is denoted by b, the following formulae (1) and (2) are satisfied: a≥5.0 (1); and a/b≥4.3 (2).

Composite semipermeable membrane

The present invention relates to a composite semipermeable membrane including: a support membrane including a base and a porous support layer; and a separation functional layer disposed on the porous support layer and including a crosslinked aromatic polyamide, in which the separation functional layer contains sulfo groups in an amount of 7.0×10to 5.0×10g/mand includes a structure represented by the formula 1.

Composite semi-permeable membrane

The present invention relates to a porous membrane including a polymer including a polyvinylidene fluoride-based resin as a main component, and a branched polyvinylidene fluoride-based resin as the polyvinylidene fluoride-based resin, in which the polymer has a value of a of 0.32 to 0.41 and a value of b of 0.18 to 0.42, each of which is determined by approximation according to the formula 1 below from a radius of gyration <S>and an absolute molecular weight Mof the polymer which are measured by GPC-MALS (gel permeation chromatograph equipped with a multi-angle light scattering detector). <S>bM(Formula 1).

Porous membrane, composite membrane, and method for producing porous membrane

An object of the present invention is to provide a porous hollow-fiber membrane satisfying both high strength and high pure-water permeation performance and at the same time, having high bending resistance. The present invention relates to a porous hollow-fiber membrane including a fluororesin-based polymer, in which the porous hollow-fiber membrane has a columnar texture oriented in a longitudinal direction of the porous hollow-fiber membrane and when a photograph of a cross-section parallel to the longitudinal direction of the porous hollow-fiber membrane is binarized into a structure portion and a void portion, the following 1) and 2) are satisfied: 1) a proportion of an area of the void portion is from 20 to 50%, and 2) a value obtained by dividing a total of peripheral lengths of the void portions by a total of areas of the void portions is 2.0 &#x3bc;mor less.

Porous hollow fiber membrane

The present invention provides a porous hollow fiber membrane that has both high strength and high pure water permeability, and that exhibits excellent thermal deformation resistance. The present invention is related to a porous hollow fiber membrane containing a fluororesin-based polymer, and a manufacturing method of the membrane comprises a drawing step and a relaxing step. The porous hollow fiber membrane is characterized in that: the molecular chain of the polymer is oriented in the longitudinal direction of the hollow fiber membrane; and at the same time internal distortion of oriented non-crystalline chains, which is disadvantageous in terms of entropy, is alleviated.

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Shiga, Japan

Takaaki Yasuda