Composite hollow fiber membrane and hollow fiber membrane module

Patent metadata

Field	Value
Publication number	US-9694326-B2
Application number	US-201314388616-A
Country	US
Kind code	B2
Filing date	Mar 29, 2013
Priority date	Mar 30, 2012
Publication date	Jul 4, 2017
Grant date	Jul 4, 2017

Abstract

This composite hollow fiber membrane comprises a gas-permeable non-porous homogeneous layer which has a polyolefin resin (A) as the main component and a porous support layer which is made of a polyolefin resin (B) and which supports said non-porous homogeneous layer, and the composite hollow fiber membrane is characterized in that the polyolefin resin (A) of non-porous homogeneous layer is a block copolymer of ethylene units and at least one type of olefin unit selected from α-olefin units having a carbon number of 3-20. By this means, a gas-permeable composite hollow fiber membrane is provided which has good gas permeability, reduces the impact of condensate on the performance of a gas dissolving module, and has excellent elution properties.

First claim

The invention claimed is:

1. A composite hollow fiber membrane comprising: a non-porous homogeneous layer that is gas permeable comprising a polyolefin resin A in an amount of at least 90% by mass; and a porous support layer comprising a polyolefin resin B in an amount of at least 90% by mass that supports the non-porous homogenous layer, wherein the polyolefin resin A of the non-porous homogeneous layer is a block copolymer of ethylene units and at least one type of olefin units selected from C3 to C20 α-olefin units,
wherein the polyolefin resin A of the non-porous homogeneous layer has a melting point of at least 100° C. to no higher than 135° C.

2. The composite hollow fiber membrane according to claim 1 , wherein the α-olefin units of the non-porous homogeneous layer are C6 to C20 α-olefin units.

3. The composite hollow fiber membrane according to claim 2 , wherein the α-olefin units of the non-porous homogeneous layer are 1-octene units.

4. The composite hollow fiber membrane according to claim 1 , wherein oxygen permeability (JISK7126) at 25° C. of the polyolefin resin A of the non-porous homogeneous layer is at least 50×10 −16 mol·m/m 2 ·s·Pa.

5. The composite hollow fiber membrane according to claim 1 , wherein moisture permeance at 25° C. of the polyolefin resin A of the non-porous homogeneous layer is no more than 3.00×10 −3 g/m·24 hr.

6. The composite hollow fiber membrane according to claim 1 , wherein the porous support layer supporting the non-porous homogeneous layer is disposed on an outer-layer side of the non-porous homogeneous layer, and the non-porous homogeneous layer is disposed in a region within 1/10 to ¼ of the membrane thickness from an inner most surface of the hollow fiber membrane in a membrane thickness direction.

7. The composite hollow fiber membrane according to claim 1 , wherein the density of the polyolefin resin A of the non-porous homogeneous layer is 0.86 to 0.89 g/cm 3 .

8. The composite hollow fiber membrane according to claim 1 , wherein the MFRD of the polyolefin resin A of the non-porous homogeneous polyolefin resin A measured in conformance with code D of JIS K7210 is 0.1 to 1.0 g/10 min·190° C.

9. The composite hollow fiber membrane according to claim 1 , wherein the ethylene unit content of said olefin block copolymer of said polyolefin resin A is 25 to 97 mol %.

10. A hollow fiber membrane module comprising the gas-permeable composite hollow fiber membrane according to claim 1 .

Assignees

• Mitsubishi Rayon Co
• Mitsubishi Rayon Co

Inventors

• Shibata Noritaka

Classifications

• B01D71/80

  Block polymers · CPC title

• B01D2325/04

  Characteristic thickness · CPC title

• B01D2325/32

  Melting point or glass-transition temperatures · CPC title

• B01D53/22

  by diffusion (manufacturing semi-permeable membranes B01D67/00; form, structure or properties of semi-permeable membranes B01D69/00; material for semi-permeable membranes B01D71/00) · CPC title

• B01D69/12

  Composite membranes; Ultra-thin membranes · CPC title