JPS60225606A - Gas permselective membrane - Google Patents

Abstract

PURPOSE:To obtain gas permselective membrane having increased coefficient of gas transmission and high mechanical strength, by using a graft copolymer obtained from a cellulose derivative and single terminal reactive polyorganosiloxane. CONSTITUTION:A cellulose derivative represented by formula is used wherein X1-X6 are selected from a group consisting of a hydrogen atom, a lower alkyl group, an acetyl group, a benzyl group, a vinylbenzyl group, a vinyl group, a hydroxyethyl group, a nitro group and an alkoxycarbonyl group, provided that at least one of X1-X6 is a hydrogen atom, a hydroxyethyl group, a vinyl group or a vinylbenzyl group. This compound must have a functional group such as a hydroxyl group or a vinyl group capable of reacting with the reactive terminal of single terminal reactive polyorganosiloxane. As the reactive terminal of single terminal reactive polyorganosiloxane, a hydrosilyl group, a halosilyl group or an epoxy group are designated. The graft copolymer of both compounds is formed into a membrane by a known method. A membrane having a thickness of about 0.05-100mum is pref. from the aspect of gas permeability and mechanical strength.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to selectively permeable membranes for gas mixtures. In particular, the present invention relates to a selective gas permeable membrane that condenses oxygen gas in the air and has a high oxygen permeability and excellent permselectivity and film forming properties.

Techniques for separating oxygen from a gas mixture, especially techniques for separating and concentrating oxygen from air, are useful. If air richer in oxygen or air richer in nitrogen than air can be produced easily and economically, various internal combustion engines can be used.

It is believed that it will make a significant contribution to fields such as the steel industry, food industry, medical equipment, and waste treatment.

Conventionally, methods for separating and concentrating oxygen and nitrogen gas from air have generally been carried out by cryogenic separation, which takes advantage of the difference in boiling point between the two gases, and adsorption, which takes advantage of the difference in adsorption amount. Both require large equipment and have drawbacks such as high energy costs. In recent years, a separation method using polymer membrane permeation has been expected as an oxygen separation method that consumes less energy and has relatively simple equipment and operation compared to these methods.

The desired characteristics of a polymer membrane used for such purposes are a high ratio of the permeability coefficients of oxygen gas to nitrogen gas and a large permeation amount of oxygen gas. In particular, the latter is extremely important in downsizing the separation device and increasing the amount of gas that can be processed. In order to obtain a large amount of oxygen gas permeation, choose a membrane material with a large oxygen gas permeability coefficient po.
In addition, it is necessary to make the thickness of the film as thin as possible.

Among the polymer membranes known so far, the permeability coefficient P for large gases (hereinafter, unless otherwise specified, the unit of permeability coefficient is c!(S T P )・am/cd*sec*(y
Let it be lHg. ) is polydimethylsiloxane. The permeability coefficient po of the oxygen gas is (SX10', the separation coefficient α of oxygen gas and nitrogen gas (α - permeability coefficient of oxygen gas/permeability coefficient of nitrogen gas) is 20. However, polydimethylsiloxane is Since the mechanical strength is low, if the thickness is less than several tens of micrometers, it is impossible to obtain a membrane that can withstand actual use.For this reason, it is difficult to obtain a membrane that has a sufficient amount of gas permeation.

For example, block copolymers of polydimethylsiloxane and polycarbonate or polyα-methylstyrene have been developed for the purpose of improving this film-forming property, but the oxygen gas permeability coefficient po2 decreases and the separation coefficient It could not be said that the results were necessarily satisfactory, as the results were insufficient. In addition, attempts have been made to mix cellulose polymers and silicon compounds for the purpose of improving the permeability of cellulose polymers. C) JP-A-59-16504) However, the silicon compound used has no reactivity with the cellulose polymer, or even if it has reactivity, the reactivity is low, and it tends to gel due to the reactivity at both ends. Therefore, it has been difficult to maintain mechanical strength and increase the content of silicon compounds.

Therefore, the permeability of the obtained semipermeable membrane was low, and was only slightly higher than the permeability of the raw material cellulose polymer.

The present inventors investigated the amount of lead in a membrane material that has excellent permselectivity for oxygen gas and has sufficient mechanical strength to be able to be made into a thin film. As a result, the inventors of the present invention discovered that a polyorganosiloxane with one end reactivity was reacted with a cellulose derivative. The graft copolymer obtained by this process is soluble in organic solvents without gelation, and the film obtained from this copolymer has sufficient mechanical strength to be made into a thin film and has a low siloxane content of 1. is 50
It was discovered for the first time that it has a high gas permeability of up to 80 mola%, and also a high separation coefficient, leading to the completion of the present invention.

That is, the present invention provides a selective gas permeable membrane made of a graft type copolymer obtained from a cellulose derivative and a polyorganosiloxane having a reactive reaction at one end.

In particular, the cellulose derivative in the present invention has the following general formula: %formula% (In the formula, X and ~X6 are hydrogen atoms and lower alkyl groups.

It is selected from the group consisting of acetyl group, benzyl group, vinylbenzyl group, vinyl group, hydroxyethyl group, nitro group, and alkoxycarbonyl group. However, at least one of X and -X6 is a hydrogen atom, a hydroxyethyl group, a vinyl group, or a vinylbenzyl group. ) are preferred. This compound has a hydroxyl group or a vinyl group that can react with the reactive end of the polyorganosiloxane having a one-end reactivity (for example, the general formula [■] described below or the reactive end Y of the one-end reactive polysiloxane represented by II). It is necessary to have functional groups such as
For example, methylcellulose, ethylcellulose, flobylcellulose, phthylcellulose, acetylcellulose, benzylcellulose.

Vinylbenzyl cellulose, vinyl cellulose.

Hydroxyethylcellulose, nitrocellulose.

Examples include cellulose acetate. These cellulose derivatives are commercially available, or can be easily synthesized from raw material cellulose by known or well-known means.

Examples of the reactive end of the single-end reactive polyorganosiloxane used in the present invention include a hydrosilyl group, a halosilyl group, a lower alkoxysilyl group, a di(lower alkyl)aminosilyl group, a halocarbonylalkyl group, and an epoxy group. As the one-end reactive polyorganosiloxane, a compound represented by the following general formula (II) or [■] is advantageously used.

(In the formula, R1 to R0 are a methyl group, an ethyl group, or a vinyl group.

Phenyl group, benzyl group, β-phenethyl group, carbon number 1
~12 halogenated alkyl group or polyfluoroalkoxyalkyl group, pentafluorophenyl group, pentafluorophenyl alkyl group.

selected from the group consisting of a pentafluorophenoxyalkyl group, a polyfluoroalkylmethyloxycarbonyl group, and Y is a hydrogen atom, a halogen atom, a methoxide group, an ethoxide group, and a dimethylamino group.

It is selected from the group consisting of diethylamino group, dipropylamino group, dimethylchlorosilylethyl group, dimethylaminodimethylsilylethyl group, diethylaminodimethylsilylethyl group, halocarbonylalkyl group, and terminal epoxidized alkyl group. m is an integer of 10 or more. ) The single-end reactive polyorganosiloxane used in the present invention can be synthesized, for example, by the following method.

As a first method, as shown in the reaction formula below, a cyclosiloxane compound is subjected to living anionic polymerization using a silal anion obtained by adding an equimolar amount of n-BuLI to a trisubstituted silanol as an initiator. It can be synthesized by stopping the reaction using a chlorosilane compound having a substituent.

R, R5 (where l is an integer from 3 to O) In this production method, polyorganosiloxane having an arbitrary degree of polymerization can be obtained by adjusting the ratio of the charged amounts of trisubstituted silanol and cyclosiloxane compound. . The trisubstituted silanol used in the above method is
For example, M3 cII.

(However, l is an integer from 1 to 10) etc. can be exemplified.

As the cyclosiloxane compound used in the production of the one-end reactive polyorganosiloxane, for example, the following can be used (where l is an integer from 3 to O). In addition, the present inventors have already discovered a method for producing the same.

General formula (wherein Z is a perfluoroalkyl group or perfluoroalkoxy group having 1 to 12 carbon atoms, a pentafluorophenyl group, or a pentafluorophenoxy group.

It is a polyfluoroalkylmethyloxycarbonyl group, P is 2 to 4, X and y are positive integers, x 10y
= 3-6, x/y is 0.2-5.0. )
By using the cyclosiloxane derivative represented by the above, it is possible to lead to the one-terminally reactive polyorganosiloxane represented by the general formula (1).

Examples of the cyclosiloxane derivative represented by the general formula (III) include CF.

II I CH2-C-CF, CF, CF3 CH21 CF30 (-CF, KiCF.

1 CH2CH.

1 Crystal 2 ■ 0 = C-0C1I2+CF2 Key-CF2H Product 2 CH2-0-CH2 (-CF', YaCF3, etc. can be exemplified.

Examples of the chlorosilane compound used as a terminator when producing the one-end reactive polysiloxane include CH3CH3, and the functional group possessed by these chlorosilane compounds can be arbitrarily introduced into the terminal of the polysiloxane. I can do it.

Furthermore, as a second method, using the polysiloxane hydrosilylated at one end obtained by the above method, a chlorosilyl group and a dimethylaminosilyl group are formed at one end according to the hydrosilylation reaction as shown below.

Reactive functional groups such as chlorocarbonyl alkyl groups can be introduced.

R2R,R.

1 1 1 (In the formula, R1...R7 are the same as above, q is an integer of 0 to 5) "The use of a catalyst is essential for the hydrosilylation reaction described in 1, and chloroplatinic acid is used as the catalyst. is the most common, but other metal complexes containing palladium or rhodium can also be used.

The reaction is preferably carried out in a solvent, and examples of the solvent include hexane, benzene, toluene, and acetone.

Trichlorethylene, carbon tetrachloride, THF, etc. can be used. The reaction temperature is preferably in the range of 60°C to 160°C, and preferably in an atmosphere of an inert gas such as argon or nitrogen.

The cellulose-based graft copolymer having polyorganosiloxane in a side chain in the present invention can be obtained by reacting the one-end reactive polyorganosiloxane obtained by the above method with a side chain hydroxyl group, vinyl group, etc. of a cellulose derivative. be synthesized. For example, under an inert gas atmosphere, a cellulose derivative is mixed with a chlorosilyl group or a methoxide silyl group in an organic solvent.

dimethylaminosilyl group, halocarbonylalkyl group,
It is reacted with a polyorganosiloxane that is reactive at one end and has a functional group capable of reacting with a hydroxyl group such as an epoxidized alkyl group at the end. Examples of solvents include dichloromethane,
Chloroform, carbon tetrachloride, THF, DMSO, etc. can be used.

In addition, using a polyorganosiloxane having a hydrosilyl group at one end, a hydrosilylation reaction with a cellulose derivative such as vinyl cellulose or vinyl benzyl cellulose having a carbon-carbon double bond in the side chain in the presence of a catalyst such as chloroplatinic acid can be carried out. A graft type copolymer can be synthesized by

The method for forming a film of the graft copolymer of the present invention is not particularly limited, and any known or well-known means can be used. For example, a film can be formed from a casting solution by evaporating the solvent on a glass plate, water surface, etc. Alternatively, methods such as immersing a porous support in a solution and then pulling it up, or applying the solution and drying it can be adopted.

The membrane of the present invention preferably has a thickness of 0.05 to 100 .mu.m% and 0.1 to 50 .mu.m in order to provide sufficient gas permeation and have practical strength. Membrane filling is 1
For thin films of μm or less, it is preferable to use them together with a support.As the support, porous materials with sufficient strength to support the membrane, such as woven fabric supports, non-woven fabric supports, microfilters, and ultrafiltration membranes. If so, you can use this.

The membrane of the present invention can be used in any form, such as a flat membrane, a tubular membrane, or a hollow fiber membrane.

The gas permeability coefficient of the graft-type copolymer membrane having polysiloxane chains as side chains of the present invention is significantly increased compared to a membrane obtained from a cellulose derivative as a raw material.

On the other hand, the separation coefficient α between oxygen gas and nitrogen gas was approximately 6 or more, indicating that it was an excellent selectively permeable membrane. moreover,
It has been found that a membrane made of a graft copolymer obtained by reacting a polyorganosiloxane synthesized using a cyclosiloxane having a fluorine-containing substituent has particularly excellent selectivity to oxygen gas.

Furthermore, since the graft copolymer of the present invention has a cellulose skeleton in its main chain, it has high mechanical strength and excellent film-forming properties, and can be formed into a thin film of about 0.1 to 20 μm. there were.

In addition, the selective gas permeable membrane of the present invention can be easily manufactured using the above-mentioned method, and since the cellulose derivative that is the backbone polymer of the copolymer is extremely inexpensive, the manufacturing cost is also low. Industrially advantageous.

Hereinafter, the present invention will be explained in more detail with reference to Examples and Reference Examples. However, it goes without saying that the present invention is not limited to these.

In the present invention, the gas permeability coefficient P was measured using a high vacuum pressure method.

- Decoration ↓ Triethylsilanol 0.61,! 9 (4,14mm
ol) in 10 mA' of dry THF and diluted with 2.6 Brnol/l of n-BuL under an argon gas flow.
1 hexane solution 1.80ml (4,82mrnoJ)
added. After stirring for 10 minutes, an additional 18.31 g (0,248 m
oJ) dried in THF7Dm/! Add the solution dissolved in
The mixture was stirred at room temperature for 22 hours under a stream of argon gas.

Add dimethylchloride 70.80 to this solution as a stopper.
ml (7.54 mmo/) was added to stop the living polymerization. Next, the solvent was removed under reduced pressure, and the resulting salt was filtered off, and unreacted cyclosiloxane and excess terminator were removed by heating at 200°C for 6 hours under a vacuum of 0.1 yn Hg or less. However, a colorless and transparent viscous liquid16.7
9.1it (yield 92t) was given. The obtained polymer was subjected to IR measurement and H-NMR measurement, and it was confirmed that the structure was as follows. Further, the degree of polymerization m was about 35 to 40 based on the proton ratio in NMR.

Polyorganosiloxane 349 thus obtained
g was dissolved in 20 ml of dry toluene, and under an argon gas flow, 0.5 ml of vinyldimethylchlorosilane and a chloroplatinic acid ethanol solution (0.193 ml) were added as a catalyst.
le/d) was added, and the mixture was heated and stirred at 80°C for 1.5 hours. When this solution was subjected to IR measurement, the absorption peak (2175 cm, ') based on the 5i-H bond at the end of the polyorganosiloxane raw material had completely disappeared. Next, after cooling this solution to room temperature, it was gradually added to a solution of 1,50.9 ml of ethyl cellulose (ethoxylation rate: 49% T 45 cps) and 13 ml of dry pyridine dissolved in 50 ml of methylene chloride at room temperature under a stream of argon gas. After the dropwise addition, the mixture was further stirred at room temperature for 19 hours.

This solution was poured into 500 ml of methanol-water (7030 vol 1%) mixed solvent. The resulting white precipitate was further dissolved in 50 ml of acetone, and again 5 ml of methanol-water mixed solvent was added.
A white solid was obtained by reprecipitation at 00 m/' and separation by filtration.

This was further dried under vacuum at 60° C. for 24 hours to obtain 326 g of the intended graft copolymer.

According to IR, about 62 of the hydroxyl groups of the raw material ethyl cellulose had reacted, and according to NMR, the siloxane content in the copolymer was 80 mθ+e%.

The obtained graft copolymer was dissolved in THF.

A 5 wt% solution was prepared, and this solution was cast onto a glass plate.
After evaporation of the solvent and drying, a cast film with a thickness of 26.9 μm was obtained. This membrane was attached to a permeation test device and the permeation rates of oxygen gas and nitrogen gas were measured at 25°C. As a result, the oxygen gas permeability coefficient PO2 was 1.01x10-'cl (S T
P)ryn/crl-5eC-crnHg, the permeability coefficient ratio α of oxygen gas and nitrogen gas was 302.

-Consideration 1 42.2 g (0,327 mol) of dimethyldichlorosilane and 27.61 g (o, o s 1 mol) of heptafluoroisopropoxypropylmethyldichlorosilane
was dissolved in ether 20(]II+/, and this solution was added dropwise to a mixed solution of ether 20 (Jml) and pure water (4DDynl) at room temperature under an argon gas stream for about 5 hours for cohydrolysis. Dropwise addition completed. After that, only the oil layer was taken out from the reaction solution, neutralized and washed with an aqueous IJ solution and pure water, dried using magnesium sulfate, and distilled under reduced pressure.
A cyclosiloxane mixture 604I having a structure with a boiling point range of .degree. C. was obtained. As a result of NMR measurement, the average composition of this cyclosiloxane was x/y = 72/28 (mole%).

Kanseigu λ- Triethylsilanol 0.171 (1,15mnno
A was dissolved in 10 m/d of dry THF, and under an argon gas flow, 0.50 ml (1.34 mmol) of a 2.68 mol/l n-BuLi hexane solution was added and stirred for 10 minutes. In the C formula, x/y = 73 / 27 mole%, x + y
Cyclosilxane compound 1285f/(97.8mmoA!) having a structure of = 3~5) was dried T
A solution dissolved in 50 ml of H'F was added, and the mixture was stirred at room temperature for 22 hours under an argon gas stream. Add 0.30 ml of dimethylchlorosilane (2,
75 mmol) was added to stop the living polymerization. Next, the solvent was removed under reduced pressure, and the salt formed was filtered off.
When unreacted cyclosiloxane and excess terminator were removed by heating at 200°C for 6 hours under a vacuum of 1 miHg or less, 112 g of a colorless and transparent viscous liquid (yield: 55%) was obtained.
gave. The obtained polymer was measured by IR measurement 'H-
NMR measurement and F-NMR measurement confirmed that the structure was , and the composition ratio x/y was 74/2.
6mole%2 degree of polymerization m was about 20-25.

Polyorganosiloxane 2.2 thus obtained
4.1i' was dissolved in 20 ml of dry toluene, and 0.4 ml of vinyldimethylchlorosilane was added under an argon gas flow.
l and a chloroplatinic acid ethanol solution (0,1
93 mole/l) was added thereto, and the mixture was heated and stirred at 80°C for 15 hours. When this solution was subjected to IR measurement, the absorption peak (2175CM-1) based on the 8i-H bond at the terminal end of the raw material polyorganosiloxane (2175CM-1) had completely disappeared. Next, after cooling this solution to room temperature, ethyl cellulose (
Ethoxylation rate 49qb.

45 cps) 1.5 op and dry pyridine 1.
In a solution of 3 m, l dissolved in 50 methylene chloride,
The mixture was gradually added dropwise at room temperature under a stream of argon gas, and after the addition was completed, the mixture was further stirred at room temperature for 18 hours. This reaction solution was added to a methanol-water (70150vol 1%) mixed solvent of 500%
mA! and add 50ml of acetone to the resulting white precipitate.
Dissolved in J. Then again methanol-water mixed solvent 50
A white solid was obtained by reprecipitating at 0 m/m and separating by filtration.

This was further dried under vacuum at 60°C for 24 hours to obtain the desired graft copolymer 2.90, p.

According to IR, about 3 of the hydroxyl groups in the raw material ethylcellulose
According to NMR, the siloxane content of this copolymer was 50 moles.

The obtained graft copolymer was dissolved in THF to make a 5 wt% solution, and this solution was cast on a glass plate, and the solvent was evaporated.
After drying, a cast film with a thickness of 14.2/Am was obtained.

This membrane was attached to a permeation test device and the permeation rates of oxygen gas and nitrogen gas were measured at 25°C. As a result, the oxygen gas permeability coefficient po was 4.40X10'cnl< S T P > α
/cTI-sec·α, the permeability coefficient ratio α of oxygen gas and nitrogen gas was 3.96.

Humanity Darkness - Triethylsilanol Q, 5511 (2,37mrno
1) was dissolved in 10 ml of dry THF, and 2.68 mol/l of n-BuL [hexane solution 1, 10 ml (2.95 mmol)] was added under an argon gas flow. 10
After stirring for a minute, (3,5,3-)lifluoropropyl)methylcyclosiloxane (manufactured by Chisso Corporation) 3
1,111 (0,199mol) dried in THF70m
A solution dissolved in / was added, and the mixture was stirred at room temperature for 15 hours under an argon gas stream. Add 0.5 ml (4,59 mrnol) of dimethylchlorosilane to this solution as a stopper.
) was added. Next, after removing the solvent under reduced pressure, the formed salt was filtered out and heated at 200°C under a vacuum of 0.1 t*Hg or less.
When heated for 5 hours to remove unreacted cyclosiloxane and excess terminator, a colorless and transparent viscous liquid 14
62 g (yield 48 g) was given. The obtained polymer was subjected to IR measurement and H-NMR measurement, and its structure was C, H, CH, CH.

It was confirmed that 1. Further, the degree of polymerization m was about 28 based on the proton ratio in NMR.

Polyorganosiloxane thus obtained 3.2
21/ was dissolved in 20 m of dry toluene, and 0.5 rnl of vinyldimethylchlorosilane was dissolved under an argon gas flow.
and chloroplatinic acid ethanol solution C0,19 as a catalyst
3 mol/l) was added, and the mixture was heated and stirred at 80°C for 1.5 hours. When this solution was subjected to IR measurement, the absorption peak (2175α-') based on the El--H bond at the end of the raw polyorganosiloxane had completely disappeared. Next, after cooling this solution to room temperature, ethyl cellulose (
Ethoxylation rate 49%, 45 cps) 1.81, j
i' and dry pyridine 1.5F/methylene chloride 50
The mixture was gradually added dropwise into a solution of 1,000 ml and 1,000 ml at room temperature under an argon gas stream, and after the dropwise addition was completed, the mixture was further stirred for 17 hours. This solution was poured into 500rnt of a methanol-water (70-30vol%) mixed solvent.

The resulting white precipitate was further dissolved in 50 ml of acetone, and again in 500 ml of methanol-water mixed solvent! A white solid was obtained by reprecipitating and separating by filtration. further under vacuum 6
After drying at 0° C. for 24 hours, 255 g of the desired graft copolymer was obtained. According to TR, about 42% of the hydroxyl groups in the raw material ethyl cellulose have reacted, and NMR
According to the study, the siloxane content of the copolymer was 65%.

The obtained graft copolymer was dissolved in chloroform, and 5
This solution was made into a wt% solution, and this solution was cast on a Teflon plate, and the solvent was evaporated and dried to obtain a cast film with a thickness of 152 μm. This membrane was attached to a permeation test device and the permeation rates of oxygen gas and nitrogen gas were measured at 25°C. As a result, the oxygen gas permeability coefficient PO□ was 188x 1 o-8♂ (STP) α/d
・sec・α~, the permeability coefficient ratio α of oxygen gas and nitrogen gas was 295.

Cold Soil 1.95 Ii of one-end hydrosilylated polydimethylsiloxane obtained in Example 1 was dissolved in 25 ml of dry toluene, and 0.95 Ii of acrylic acid chloride was dissolved under an argon gas stream.
3mj! and chloroplatinic acid ethanol solution (0,193
7 μl of moil/l) was added, and the mixture was heated and stirred at 80° C. for 2 hours. When this solution was measured by IR measurement, the absorption peak (2175α-') based on the 5l-H bond at the end of the raw material polydimethylsiloxane completely disappeared, and a new absorption peak (1550cm-'') based on the carbonyl group was found.
appeared. Next, after cooling this solution to room temperature, ethyl cellulose (ethoxylation rate 49%, 45 cpa) 1.5
0.9 and 1.3 ml of dry pyridine dissolved in 50 ml of methylene chloride were gradually added dropwise at room temperature under an argon gas stream, and after the addition was completed, the mixture was further stirred at room temperature for 19 hours.

This solution was poured into 500ml of a methanol-water (7050vol%) mixed solvent. The resulting white precipitate was further dissolved in 50 ml of acetone, and again dissolved in 50 ml of methanol-water mixed solvent.
A white solid was obtained by reprecipitating at 0 m/m and separating by filtration.

This was further dried under vacuum at 60° C. for 24 hours to obtain 297 g of the intended graft copolymer. According to IR, about 64% of the hydroxyl groups of the raw material ethylcellulose had reacted, and according to NMR, the siloxane content in the copolymer was 74 mole%.

The obtained graft copolymer was dissolved in THF to give a concentration of 5 wt%.
This solution was cast on a Teflon plate, and the solvent was evaporated and dried to obtain a cast film with a thickness of 11.4 μm. This membrane was attached to a permeation test device and the permeation rates of oxygen gas and nitrogen gas were measured at 25°C. As a result, the oxygen gas permeability coefficient PO□ was 7.96X10-'cm' (S T P )
am/crl ・Sec ・aHg + The permeability coefficient ratio α of oxygen gas and nitrogen gas was 6.21.

Claims (3)

[Claims] (1) A selective gas permeable membrane comprising a graft copolymer obtained from a cellulose derivative and a polyorganosiloxane with one end reactive. (2) General formula (wherein, (However, at least one of X1 to X0 is a hydrogen atom, a hydroxyethyl group, a vinyl group, or a vinylbenzyl group.) The selective gas according to claim 1, which uses a cellulose derivative represented by Transparent membrane. (3) General formula (wherein R1 to R0 are methyl group, ethyl group, vinyl group,
Phenyl group, benzyl group, β-phenethyl group, carbon number 1
-12 halogenated alkyl groups or polyfluoroalkoxyalkyl groups, pentafluorophenyl groups, pentafluorophenylalkyl groups, pentafluorophenoxyalkyl groups, polyfluoroalkylmethyloxycarbonyl groups, Y is a hydrogen atom, Halogen atom, methoxide group, ethoxide group, dimethylamino group. It is selected from the group consisting of diethylamine group, dipropylamino group, dimethylchlorosilylethyl group, dimethylaminodimethylsilylethyl group, diethylaminodimethylsilylethyl group, halocarbonylalkyl group, and terminal epoxidized alkyl group. m is an integer of 10 or more. 2. The selective gas permeable membrane according to claims 1 and 2, which comprises using a polyorganosiloxane having a one-terminal reactivity represented by: