JPS627418A - Gas separation composite membrane and its preparation - Google Patents

Abstract

PURPOSE:To obtain a gas separation composite membrane excellent in separability and permeability and also having good durability, by providing a gas permeable polymer layer and a silicon atom-containing polyarylene oxide layer on a porous support. CONSTITUTION:A porous support having fine pores with a pore size of 10- 10,000Angstrom is used. A layer comprising a polymer having gas permeability and a layer comprising polyarylene oxide containing a silicon atom are provided on said support. The former layer has oxygen transmission coefficient of at least 10<-9>cm<3>cm/cm<2>seccmHg and the thickness thereof is pref. 0.01-3mum while the latter layer is formed by using polyarylene oxide having an organosilil group. At least one organosilil group is necessarily contained per 1-98% of the constitutional unit of polyarylene oxide. The thickness of the latter layer is pref. 0.01-1mum.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a composite membrane for gas separation that is used to separate mixed gases and has good selectivity, permeability, and durability, and a method for producing the same. .

(Prior art) Recently, separation technology using membranes has made remarkable progress, and has been put to practical use on an industrial scale in fields such as seawater desalination, ultrapure water production, and wastewater treatment. Hydrogen, hydrocarbons, carbon dioxide, etc. have also been investigated in the separation of gases.

One example of the application of such membranes to gas separation is the production of oxygen-enriched air. Oxygen-enriched air is required in the medical field for respiratory diseases, etc., and in the industrial field for combustion systems, etc., and has a wide range of applications.

Normal combustion systems (boilers, for example) use air in addition to fuel, but if oxygen-enriched air with increased oxygen concentration is supplied to the combustion system instead of this air, fuel efficiency and combustion temperature can be improved. It is possible to reduce the amount of combustion waste, and it is expected to be effective in both energy saving and pollution prevention.

Despite these expectations, gas separation using polymer membranes has hardly been put into practical use on an industrial scale, and practical application is only beginning to materialize in limited fields such as hydrogen separation. .

One of the reasons why the practical application of gas separation using polymer membranes has not progressed is that there has been a delay in the development of membrane materials that have excellent gas permeability and gas separation properties and can be easily made into thin films. . Generally, the gas permeability and gas separation properties of polymer membranes tend to contradict each other, and in order to overcome this, various methods are being considered to form composite membranes.

The gas permeation rate (Q) of a polymer membrane used for the production of oxygen-enriched air or for gas separation is generally expressed by the following formula (%), where P is the permeation coefficient (ci - cm/cd -sec
-cmHg), △p is the partial pressure difference of the permeate gas on both sides of the membrane (
cmHg), A is the membrane area (cJ>, Q is the membrane thickness (cm
) is shown. The gas separation property of a polymer membrane is unique to the polymer membrane and does not depend on the membrane thickness. On the other hand, gas permeability is
As shown in the above equation, the improvement can be achieved by thinning the film, so the key point when it comes to vehicle equipment for separation membranes is how thin the membrane material with gas separation properties can be made into a homogeneous membrane with no defects.

From this point of view, composite membranes for gas separation with various configurations have been devised. For example, in U.S. Patent No. 3,874,986g, an organopolysiloxane layer is formed between a porous support and a thin film layer made of polyphenylene oxide and organoborisiloxane-polycarbonate 1 to copolymer, which also functions as a contact and a cushion. A laminated composite membrane having an intermediate layer made of Sun-Polycarbone-1 or copolymer has been proposed. Further, in the specification of US Pat. No. 3,980,456, a thin film layer is roughly provided on the laminated composite film to cover pinholes caused by the incorporation of fine particles. However, since such laminated composite membranes use a thin film layer made of two types of polymers as the separation active layer, membrane performance (separability and permeability) or durability may not necessarily be sufficient due to phase separation, etc. do not have. Furthermore, JP-A No. 57-4203 proposes a composite membrane in which the surface of a membrane using poly-4-methylpentene is coated with a substance that does not have film-forming ability. Although separation performance is improved, durability is considered to be a problem because there is a layer of a substance that does not have film-forming ability on the membrane surface.

Furthermore, in Japanese Patent Application Laid-open No. 60-216802, a gas separation membrane is devised in which silylated polyphenylene ether is coated on a thin porous retaining material, but the separation layer is made of silylated polyphenylene ether. Since it is formed from only layers, the mechanical properties of the separation layer are insufficient, and the durability and reproducibility of membrane performance are not always fully satisfactory.

[Problem that the invention attempts to solve]

An object of the present invention is to provide a composite membrane for gas separation that does not have the drawbacks of the conventional examples as described above, that is, a composite membrane for gas separation that has excellent separation properties and permeability, and is also good in durability. do.

[Failure to solve the problem]

In order to achieve the above object, the present invention consists of the following configuration.

[At least the following (A) and (B) on the porous support
A composite membrane for gas separation characterized by having two layers.

(A) Layer made of a polymer having gas permeability (A) Layer made of polyarylene oxide containing silicon atoms. The size of the micropores that exist or the separation of the thin film that covers the stack 17f
10 to 10,000 people, preferably 10 to 2,000 people, in order to effectively express the characteristics of
It's a person. As a porous support, extraction method, layer separation method,
Organic porous supports or non-porous supports made by various methods such as stretching methods and firing methods are used. Organic porous supports (small mobolymers such as polysulfones, celluloses, polyolefins, polyesters, polyamides, polyimides, etc., or blends of these polymers are usually used, but are particularly limited to these) As for the shape of the porous support, in addition to the shape of a flat membrane, hollow fiber shapes, tube shapes, etc. can be used.

The polymer constituting the layer (A) made of a polymer having gas permeability means, for example, when oxygen permeability coefficient Po2 is used as a measure of permeability, Po2 is at least 10-9 (
cffl ・cm/c4-sec-cmtlg)
Above, preferably 10-0-8(-cm/CITf-s
ec-cmllg) or above. Examples of polymers with an oxygen permeability coefficient below the above range include polyorganosiloxane such as polydimethylsiloxane, silphenylene-siloxane copolymer, polycarbonate I-polysiloxane copolymer, and polysulfone-polysiloxane copolymer. polymerization, polyorganosiloxinane copolymer such as polystyrene-polysiloxane copolymer, substituted polyacetylene such as poly(tert-butylacetylene), poly(trimethylsilylpropyne), poly(dite-butyl fumarate), etc. Examples include polyolefins, polyolefins such as poly(bisethoxyphosphapine), etc., but the material is not limited to these as long as the oxygen permeability coefficient substantially satisfies the above range.

Moreover, the polymer constituting layer (A) does not adhere and support even if it has a crosslinked structure.

In addition, the thickness of the layer (A>) made of a gas-permeable polymer is generally 0.000.
It is necessary that the thickness be within the range of 01 to 3μ, preferably 09O3 to 0.5μ.

Examples of the polymer constituting the layer (B) made of polyarylene oxide containing silicon atoms include silicon-substituted polyarylene oxide, copolymers of silicon-containing polymers and polyarylene oxide, and the like. As the silicon-substituted polyarylene oxide, f) a polyarylene oxide having a lecanosilyl group is preferable. Furthermore, the copolymer of a silicon-containing polymer and polyarylene oxide may be in any state such as a random copolymer, a block copolymer, a pendant copolymer, or a pendant copolymer. Combination is more preferred.

The basic structure of the polyarylene oxide moiety contained in the polymer constituting the layer (B) made of polyarylene oxide containing silicon atoms is represented by the general formula. Here, m is an integer of 1 to 3, and n is an integer of 25 or more, preferably 50 or more.

In addition, in the aromatic ring contained in the polymer main chain, it is preferable that the oxygen atom in the general formula and the adjacent oxygen atom be connected at the para position. However, some connections may be at other positions. 'b No problem. R may be the same or 1<, each may be different, an alkyl group, a substituted alkyl group,
It is selected from a phenyl group, a substituted phenyl group, a halogen atom, an alkoxy group, an alkenyl group, an alkynyl group, an amino group, and the like.

The number of carbon atoms contained in the substituent R is preferably 15 or less, more preferably 8 or less.

The polyarylene oxide represented by the above general formula contains at least one hydrogen atom or halogen atom on the main chain aromatic ring, or at least one or more hydrogen atom or halogen atom on the carbon atom adjacent to the main chain aromatic ring. It is necessary that hydrogen atoms or halogen atoms, etc., be retained. In particular, when R is an alkyl group or a substituted alkyl group, it is necessary that at least one hydrogen is contained on the carbon atom adjacent to the main chain aromatic ring. Also, the repeating units contained in the polymer may be single or different.
Shiyoi.

As the organosilyl side, all or (some of the 71-/recanosilyl groups) hydrogen atoms d3 and 2/' or halogen atoms on the aromatic hX carbon or aliphatic carbon contained in the polyarylene A oxide formula Substituted @) blue ones, and structures in which all or part of the unsaturated bonds contained in the above general formula are bobbed with organosilyl groups.

As a yQ-type example, an example of the seven constituent units of the polyarylene oxide having an organosilyl group constituting the present invention is shown below, but the present invention is not necessarily limited thereto.

As a method for introducing an organosilyl group into the polyarylene oxide represented by the above general formula (there are various methods, metalized polyarylene oxide prepared from polyarylene oxide, halogen-containing polyarylene oxide, etc. using a metal reagent, etc.) = Coupling reaction between renoxy 1~ and organohalosilane, etc., hydrosilylation reaction to polyarylene oxide having an unsaturated bond, reaction with epoxide, isocyane 1~, organosilane having a reactive group such as a diazo group, etc. However,
Synthesis is also possible by other methods.

Preferred substituents for the silicon atom of the organosilyl group include hydrogen, an alkyl group having 1 to 2 carbon atoms, a substituted alkyl group, an alkenyl group, a phenyl group, a substituted phenyl group, and the like. Furthermore, the substituents may be the same or different. When an alkyl group is used as a substituent, the total number of carbon atoms in the three substituents is 2 to 30, more preferably 3 to 2.
A range of 4 is good. If the total number of carbon atoms exceeds 30, the mechanical strength (breaking strength, Young's modulus) of the film decreases, and the formability of the ultra-thin film decreases, which is not preferable. Specific examples of the substituent include, but are not limited to, the following substituents.

i.e. methyl, ethyl, n-propyl, isopropyl,
n-butyl, isoethyl, sec-butyl, tert-
Alkyl groups such as ethyl, neopentyl, hexyl, octyl, cyclohexyl, chloromethyl group, chloropropyl group, mercaptopropylcyanoethyl group, benzyl group, 1-lichloropropyl group, methoxyethyl group, nitropropyl group, 2-(carbomethoxy) Substituted argyl groups such as ethyl group, dichloromethyl group, trifluoropropyl group, (perflugorohexyl)ethyl group, (perfluorooctyl)ethyl group, alkenyl group such as cyclohexenyl group, vinyl group, allyl group, phenyl group , 4-methylphenyl group, 4-nitrophenyl group, 4-chlorophenyl group, 4-methoxyphenyl group, pentafluorophenyl group, and other substituted phenyl groups.

When a fluorine-containing organosilyl group is used as all or a part of the organosilyl group contained in the polymer constituting the present invention, a good balance between selectivity and gas permeability is obtained, which is preferable.

Particularly preferred substituents include (substituted) alkyl groups, J:
More preferred is a methyl group. Therefore, preferred organosilyl groups include 1-realkylsilyl M, more preferably trimedelsilyl.

The organosilyl group contained in the polyarylene oxide accounts for 1 to 98% of the constituent units of the polyarylene oxide,
Preferably, at least one of each is contained in 5 to 90%.

If the above content of organosilyl groups is less than 1%, the permeability coefficient of gas permeating through the membrane decreases, and if the content is less than 9%,
If it exceeds 8%, the mechanical strength of the film decreases and the formability of the ultra-thin film deteriorates, which is not preferable.

In addition, the organosilyl group is 1 of polyphenylene oxide.
J: Yes, even if multiple units are connected to a constituent unit. This is because, in this way, the oxygen permeability can be roughly improved.

Almost all of the organosilyl groups contained in polyarylene oxide are bonded directly to carbon atoms on the main chain aromatic ring, or almost all of the organosilyl groups are bonded to substituents formed by bonding to the main chain aromatic ring. Either of these may be used, or they may be mixed in any proportion. It is preferable when the organosilyl group is directly bonded to the carbon of the main chain aromatic In- because it effectively improves the gas permeability. Preferably, at least 3% or more of the total number of organosilyl groups are directly bonded to carbon atoms on the main chain aromatic ring.

Also, is the organosilyl group part of the main chain? When it is bonded to a substituent bonded to Ei'M, it is preferable because it improves solubility in a solvent and facilitates processing into a thin film.

Furthermore, IW (B) made of polyarylene oxide containing silicon atoms may contain a portion of the following polymer as a second component.

That is, as the second component, poly(4-methylpentene)
, poly(vinyl trimedelsilane), polystyrene, various olefinic polymers such as poly(di-tert-butyl fumarate), aromatic polyneedle such as poly(2,6-dimethyl-p-phenylene oxide), polydimethylsiloxane, Polyorganosiloxanes such as polymethylphenylsiloxane, polyorganosiloxane copolymers such as silphenylene-silokinane copolymers, polycarbonate-polysiloxane copolymers, polysulfone-polysiloxane copolymers, poly(tert) -butylacetylene), substituted polyacetylenes such as poly([-limethylsilylpropyne), and polyorganophosphosulfates such as poly(bisethoxyphosph-7bin).

Addition methods include mixing with the second component polymer,
There are lamination methods with component polymers, etc.

The thickness of the layer (B) made of polyarylene oxide containing silicon atoms is generally 0.01 mm, since mechanical strength and uniformity will decrease if it is too thick, and gas permeability will decrease if it is too thick. ~1μ, preferably 0.01~0
．． It is appropriate that the thickness be in the range of 5μ.

The silicon atom-containing polyarylene oxide used in the present invention varies depending on its composition, but generally:
Aromatic hydrocarbon solvents such as benzene, toluene, and xylene; aliphatic hydrocarbon solvents such as cyclohexane and n-hexano; halogenated hydrocarbon solvents such as chlorobenzene, chloroform, dichloromethane, and trifluorotrichloro[1-ethane] It is soluble in a single or mixed solvent such as ether solvents such as , detrahydrofuran, and di-chirin, and can be formed into a film or thin film using a solution using these as a solvent.

A layer made of a polymer having gas permeability (A>) and a layer made of polyarylene oxide containing silicon atoms (
The lamination method of B) is a method of laminating polymer thin films obtained by casting a solution of the polymer for constituting (A> or (B) onto the liquid surface and evaporating the solvent). Liquid surface development method 9 For example, the method described in Japanese Patent Application No. 12502/1982, coating methods such as dipping method, roll coating method, spray coating method, in-situ "M polymerization, interfacial polymerization method" (B) When the layer is provided by a liquid surface development method, a solution using a solvent that dissolves polyarylene oxide containing silicon atoms is poured onto a liquid that is immiscible or partially miscible with the solution. A thin film is formed by supplying and spreading the solution by various methods such as a dropping method and a continuous method, and evaporating the solution.The thin film is laminated by a method such as a contact method and a suction method. The concentration varies depending on the developing solvent and the supply method, but is preferably in the range of 0.1 to 5%.In addition, as a supporting liquid (1) one that is immiscible or partially miscible with the developing solution. If so, either can be used, or it is preferable to use water. (B
When the ) layer is provided by a coating method, the polymer content of the coating solution varies depending on the solvent used and the condition of the coated surface, but is preferably in the range of 0.01 to 5%. Any solvent may be used, but it is preferable to use a fluorine-containing solvent such as trifluorotrichloroethane. In addition, the order of lamination is (A)Ii
Suitable configurations are ffl-(B) layer-porous support, (B) layer-(A) layer-porous support, and (A) layer-(B) layer-(A) layer-porous support. I'll go. In this case, a layer made of another polymer may be interposed between each layer.

The membrane of the present invention has excellent separation properties and permeability of gas mixtures, and is capable of separating various gases such as hydrogen, oxygen, nitrogen, -carbon oxide, carbon dioxide, hydrocarbons, hydrogen sulfide, argon, helium, and sulfur dioxide. , can be used for concentration. Also,
Combustion efficiency can be improved by incorporating the membrane of the present invention into an oxygen enrichment system that produces oxygen-enriched air and using it in combustion systems such as engines, boilers, and heating appliances. Furthermore, the oxygen enrichment system can be used in medical applications such as treatment devices for respiratory diseases and premature infants, artificial lungs, artificial gills, and gas recovery applications such as nitrogen-enriched air production.

〔Example〕

The invention will be explained in further detail by the following examples.

The oxygen permeability coefficient P02 and nitrogen permeability coefficient PN2 of the films in the examples were measured at 25°C using a scum permeability measuring device manufactured by Yanagimoto Seisakusho Co., Ltd.The gas permeation rate Q in the composite membrane was Production example (1) Production of small aggregate (1) 1.2 g of poly(2,6-dimethyl-1,4-phenylene oxide) was added to anhydrous detrahydrofuran. A solution of N,N,N',N-tetramethylethylenecyamine (1.9H) and n-butyllithium in n-hexane (1,62M>7.0H) was dissolved in 100ml of water at room temperature. The mixture was stirred for 7 hours. After that, 2.0% trimethylchlorosilane was added to the reaction solution.
1...1 was added and continued stirring for about 30 minutes. After concentrating the reaction solution, it was poured into about 30 Qml of methanol and filtered to recover the ribolimer. The polymer was again reprecipitated with methanol. After purification, 1.1 g of polymer was obtained by drying under reduced pressure. In the infrared spectroscopy spectrum of this polymer, an absorption derived from the trimedelsilyl group was observed at 1250 Cm-1, and furthermore, in the proton nuclear magnetic resonance spectrum, an absorption derived from the trimedelsilyl group was observed. According to this, trimethylsilyl groups are introduced into 30% of the repeating units, of which only 1 of the repeating units are introduced onto aromatic rings, and the rest are introduced into side chain methyl groups. confirmed.

8 liquids of this polymer (5% chloroform) were cast onto a glass plate, and then dried at room temperature for one day. 1]02 of the film (homogeneous film) obtained in this way is 1,9x 1
0-”(cn-cm/ci-sec-cmtlg)
, p-10.

N2 is 4.3X10 (crn-cm/cJ-se
c・cmNg), and the separation coefficient α(=Po 2 , /
PN 2) was 4.4.

(2) Production of polymer (2) N, N, N', N'-tetramethylethylenecyamine 3
゜35ml, D-butyllithium n-hexane solution 1
A polymer was synthesized in the same manner as in the case of polymer (1) except that 2,51111 was used and the reaction time for lithiation was shortened from 7 hours to 1 hour. It was confirmed that trimethylsilyl groups are present in 50% of the repeating units of the polymer, of which 60% are on the main chain aromatic rings, and the rest are introduced into side chain methyl groups. The Po2 of the polymer is 3°5 x 10-” (ci-cm/
ci-sec-cmHg), which was more than three times that of raw polymer.

(3) Production of polymer (3) As chlorosilane (1 to Ridekafluoro-1,1°2
．． A polymer having a fluorine-containing trialkylsilyl group was synthesized in the same manner as in the case of Polymer (1) except that 2-te1-didrooctyl) dimethylchlorosilane 4.41111 was used. It was confirmed that 1-1-nor groups were present in 10% of the repeating units of this polymer.The Po2 of this polymer was 1.
, 9X 10-” (a+f ・cm/cnf @s
ec-Cmllc))? >Tsuta.

Example 1 Polydimethylsiloxane with silanol groups at both ends
9.5q), Tetrakis (2-
Dissolve 0.4q of propanone oxime) silane and 0.1Q of dibutyltin diazetate in cyclohexane to reduce the solid content to 0.
．． Prepare a 5% solution. A portion of this dilute solution was coated onto a polysulfone porous support and 130'
The mixture was dried by heating at C for 1 minute and then dried at room temperature for 1 hour to obtain a crosslinked silokinane composite membrane. The thickness of the polydimethylsiloxane layer of this composite membrane was approximately 0.1μ. The oxygen permeation rate QO2 of the composite membrane is 7.0 (m', /7))2-h
-r-arm>, and the separation coefficient α(=002,/
QN 2 ) was 2°0.

0.5 g of the polymer synthesized in the production example (1>[polymer with trimethylsilyl group]) was uniformly dissolved in 16C1 chloroform. A portion of this polymer solution was cast onto the water surface, and the solvent was volatilized at room temperature. A thin film was obtained by this process.The thickness of this thin film was approximately 70 mm based on the thin film area and the amount of solution cast.
It is estimated that there were around 0 people.

This thin film was laminated by a suction method on the crosslinked siloxane composite film prepared as described above to obtain a laminated composite 11Q. The permeation rates of various gases through this laminated composite membrane are shown in Table 1.
Separation of various gases was possible. It was also confirmed that the oxygen enrichment performance of this laminated composite membrane was good in both selectivity and permeability, as well as in terms of reproducibility of membrane performance.

Comparative Example 1 A thin film of the polymer (1) prepared in Example 1 was subjected to an air permeation rate of 100 (IT13/1T12-hr-atm).
A composite membrane was obtained by stacking three decoys on a polysulfone porous support using a suction method. Oxygen permeation rate of this composite membrane QO12
is approximately 0.2 (T11"/T11"-hr-atm)
However, the separation coefficient α (=Q02/QN2) showed a large variation of 1.5 to 3.3.

Example 2 A 0.12% solution obtained by dissolving the polymer (1) in trifluorotrichloroethane was applied onto the chestnut siloxane composite film prepared in Example 1 by a dipping method, and was not allowed to dry. A laminated composite membrane was obtained.The oxygen permeation rate QO2 of this laminated composite membrane was 1.8hr+'l/T112-h
r-atm), separation coefficient 0! , (-QO2/QN
2) was 3.2.

Example 3 Example 2 except that polymer (2) synthesized in Production Example was used.
A laminated composite membrane was prepared in the same manner as above.

The oxygen permeation rate Q02 of this laminated composite membrane is 1.8 (m'/
7712-hr-atm), minute it coefficient α is 3
．． It was 2.

Example 4 Example 2 except that the polymer (3) synthesized in the packaging example was used.
A laminated composite membrane was prepared in the same manner as above.

The oxygen permeation rate QO2 of this laminated composite membrane is 1.8<1TI
9/a2-hr-atm), and the separation coefficient α is 3.
It was 0. Comparative Example 2 Poly(4-methylpentene) (manufactured by Mitsui Petrochemical Co., Ltd., TPXMX-0) was used instead of the polymer (1) used in Example 2.
A laminated composite membrane was created using 01).

A laminated composite membrane (with an oxygen permeation rate QO2 of 1.4 (m
”/m2-hr-atm), the separation coefficient α was 3.0, and the laminated composite membranes of Examples 2 to 4 were not as good in membrane performance.

Example 5 Poly(4
A laminated composite membrane was prepared by applying a 0.06% cyclohexylene solution of (-methylbenzone) and a 0.1% 1- to fluorochloroethane solution of polymer (1) by a dipping method and drying.

The oxygen permeation rate QO2 of this composite membrane is 1.5 (m'/71
2.hr-atm), and the separation coefficient α was 3.2.

Table 1 (Effects of the Invention) The composite membrane for gas separation of the present invention has excellent permeability and selectivity, as well as good membrane strength and durability. This enables effective and economical gas separation.

Claims (10)

[Claims] (1) At least the following (A) and (
A composite membrane for gas separation characterized by having two layers of B). (a) Layer made of a polymer having gas permeability (A) (b) Layer made of polyarylene oxide containing silicon atoms (B) (2) The oxygen permeability coefficient Po_2 of the layer (A) made of a polymer having gas permeability is 1×10^-^8 [cm^3.
cm/cm^2. sec. The composite membrane for gas separation according to claim (1), characterized in that it has a property of not less than [cmHg] or more. (3) The composite membrane for gas separation according to claim (1), wherein the layer (A) made of a gas-permeable polymer is made of crosslinked polysiloxane. (4) The composite membrane for gas separation according to claim (1), wherein the layer (B) made of polyarylene oxide containing silicon atoms is made of polyarylene oxide having an organosilyl group. . (5) The polyarylene oxide having an organosilyl group is characterized in that it has an organosilyl group on an aromatic ring contained in the main chain of the polyarylene oxide and/or on a substituent bonded to the aromatic ring. A composite membrane for gas separation according to claim (4). (6) The composite membrane for gas separation according to claim (1), wherein the porous support is in the shape of a flat membrane, hollow fiber, or tube. (7) Claim (1) characterized in that the layer (B) made of polyarylene oxide containing silicon atoms is made of a thin film of polyarylene oxide containing silicon atoms and a thin film of another polymer compound. ) Composite membrane for gas separation as described in item 2. (8) It is characterized by comprising the steps of providing a layer (A) made of a gas-permeable polymer and a step of providing a layer (B) made of polyarylene oxide containing silicon atoms by a liquid surface development method. A method for manufacturing a composite membrane for gas separation. (9) Gas separation characterized by comprising the steps of providing a layer (A) made of a gas-permeable polymer and a step of providing a layer (B) made of polyarylene oxide containing silicon atoms by a coating method. Method for manufacturing composite membrane for use. (10) Claim No. 1, characterized in that the coating method uses a coating solution containing a fluorine-containing solvent.
9) A method for producing a composite membrane for gas separation according to item 9).