JPS6174627A - Gas permselective membrane - Google Patents

Abstract

PURPOSE:To obtain a gas permselective membrane capable of filming by interfacial polymerization by using a copolymer of both polyamine having at least two pieces of amino group shown by a specified formula and the cross-linking agent component having at least two pieces of functional group allowing to react with amino group. CONSTITUTION:A soln. of the following amino compd. e.g. 3-(2-amino ethylaminoproplyl)-tris (trimethylsiloxane)-silane is impregnated into a supporter wherein >=50mol% all polyamines has two or more pieces of primary and/or secondary amino group shown by the formula 1 and/or 2 and thereafter excess soln. is separated. A soln. of multifunctional compd. having two or more pieces of functional group allowing to react with amino group e.g. diphenylmethane diisocyanate is introduced onto the surface of the supporter and both the compds. are allowed to react with each other on the surface of the supporter. The gas permselective composite membrane is obtained by washing the solvent and the nonreacted compd. and drying same.

Description

[Detailed Description of the Invention] Purpose> The present invention relates to a selectively permeable membrane for gas separation used to separate a specific component, particularly oxygen gas, from a mixed gas of various families.

<Prior art> Meishin is known as a material that has excellent gas selective permselectivity, but there is no material that has excellent gas selective permselectivity and can be easily formed into a thin film with a thickness of 1 μm or less. few. Molding methods that can easily produce a thin film of 1 um or less include a water surface spreading method and an interfacial polymerization method. The present inventors would like to propose a 41 gas selective separation membrane that can be formed by interfacial polymerization and has a siloxane bond in its main chain.
(Refer to Publication No. 193703) Although this material also has excellent permselectivity, the inventors of the present invention have arrived at the present invention as a result of intensive research into materials that are even more superior and can be interfacially polymerized.

<Structure of the Invention> In the present invention, at least 50 mol% of all polyamine components is represented by the following formula (1) and/or (2) (l'-N+a A(:N-B-8i -R2) b
-...(1) A polyamine component which is an amino compound having at least two primary and/or secondary amino groups represented by ROR3 and at least two functional groups capable of reacting with the amino groups. This is a selectively permeable membrane for gas separation, characterized in that it is formed from a polymer obtained by reaction with a crosslinking agent component consisting of a polyfunctional compound.

In the formula (11, (2)), as the polyamine component,
When a bifunctional diamine is used as a crosslinking agent component, a soluble polymer can be obtained by ordinary solution polymerization or the like, and can be formed into a film by a coating method, a water surface development method, or the like.

However, as a polyamine component and/or a crosslinking agent component, 3
When using a substance more than functional, it is generally insoluble in a solvent, so it is necessary to obtain a gas selective permeation membrane by an interfacial polymerization method.

The interfacial polymerization method in the present invention refers to an amine group-containing compound having at least two primary and/or secondary amino groups, water or an organic liquid that is freely miscible with water, or a combination of such an organic liquid and water. Prepare a solution of an amine group-containing compound dissolved in a mixture, a polyfunctional compound (crosslinking agent component) having at least two functional groups that can react with the amine group-containing compound, or a solution thereof, and add one of the compounds. is impregnated into a porous support in a solution state, and then the other compound is introduced into the surface of the support in a solution or gas state to cause a reaction between both compounds on the surface of the support. Forms a permselective thin film.

Alternatively, a gas selectively permeable thin film can be formed by bringing an amino group-containing compound solution into contact with a polyfunctional compound solution, and then supporting an interfacially polymerized film formed at the interface on a support. Here, as the amino 1;4-containing compound, a polyamine represented by the above formula (1) or (2) is used.

Δ in the formula (11:1:take (2)) is a + b value or c
It is a deca-d aliphatic hydrocarbon group, aromatic hydrocarbon group or organosilyl group, and the molecular weight per amino group is 14-800, preferably 14-500. If it is less than 14, the reactivity decreases, and if it is more than 800, the strength of the film tends to decrease.

(1) In the formula, Ro is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an argyl group having 1 to 6 carbon atoms which is also bonded to A to form a ring with -Ro-N- It is. When the number of carbon atoms is 6 or more, the reactivity of the amino group decreases, which is not preferable.

(1) In the formula, a represents an integer of 1 or more, Ro may be different from each other, and a+b represents an integer of 2 or more. Further, in formula (2), C represents an integer of 2 or more.

8 in the formula (1) is an alkylene group or a phenylene group having 10 or less carbon atoms.

In the formula (1), R+, R2, and R3 each independently represent -fCHZteKCl-13 (K is 1 to 9).

Alkyl groups such as 1,000H2+, oH (p is O to 4) (however, the hydrogen atom may be substituted with a fluorine atom.If the number of carbon atoms is 10 or more, the selectivity tends to decrease), phenyl group, or -0-8i-Rs.

Ra represents one of Rn (R4 to R1+ represent an alkyl group having 1 to 6 carbon atoms). Here, R4-Rh represents an aliphatic or alicyclic alkyl group or a phenyl group (
However, some of the hydrogen atoms may be replaced by fluorine atoms).

b in formula (1) and d in formula (2) represent an integer of 1 or more, and B, R+, R2, and R3 may be different from each other.

Here, the specific structure of the polyamine is the formula (1) above.
or -13-8 represented by the following formula (3) in (2)
! -R2...(3) ■ When the silyl group is represented as X, it is 1''N (: CH2+n N H2.

× H-N
.

■ X n is 1~
Alicyclic polyamines represented by x (integer of 10 or more), etc.; Aromatic polyamines represented by GH3 N2 N(-Ct12 +n Si (-CH2+
nNN2.

CI-13 HX (n is an integer of 1 to 10, D represents a 2" square shape, etc.), and mono-iron-containing polyamines can be mentioned. However, the polyamine component is not limited to those mentioned above, and any polyamine having two or more primary and/or secondary amino groups and a silyl group represented by the above formula (3) can be used.

Preferred specific examples of polyamine compounds include 2-amino T delamizmedel 1-limethylsilane.

3-(2-aminoethylaminopropyl)hebutamethyltrisiloxane, 3-(2-aminoethylaminopropyl)tris(1-lymethylsiloxy)silane.

1"11" N [CH2CH2NiiCH2-1-3St -
(0-8i (-Ct-h)3 )3 ]2
.

(rcH2-CH2')n CH2N1-1fCH2+38i (CH3) 3HI
-1, Ct-hl 1 1 N2 NCH2CH2NCH2Cl-12N(-cH2
+3(Si-0+3Si (E-CH3) 3■ GH3 N2 NfCH2-CH2-N+n'C'H2CH2N
N2■ (C1-h -)3 Si [0-3i (-CH3
) 3 Aliphatic polyamine such as 3; dibutyl: 3
Alicyclic polyamines such as -(4-piperidylmethylaminopropyl)silane, dimethylphenyl-4-piperidylmethylaminomethylsilane, 3-(4-piperidylmethylaminopropyl)tris(1-rimedylsiloxy)silane; 3.

Aromatic polyamines such as CH3 ↓: ■ CI-13 GH3 N3 0(rsi O+n Si (CH3)3
(CH2)3 HNsoCH2-E)3 S i (E-CH3)
3H3 ■ [T12N E GH2+ 3 ] St So CH2 Mid 3 NN2 ] (CN2 Te3
Examples include silicon-containing polyamines such as 3i (-CH3)3.

Further, as the polyfunctional compound as a crosslinking agent, a compound having at least two isocyanate groups or acid chloride groups is used. (The term "crosslinking agent" here does not necessarily mean that it causes three-dimensional crosslinking.) There are no particular restrictions on the compound having at least two incyanate groups or acid chloride groups. Polyisocyanates or polyacid chlorides having 4 to 15 carbon atoms, preferably 6 to 13 carbon atoms, are used.

A specific example is toluylene diisocyanate.

Diphenylmethane diisocyanate, naphthalene diisocyanate.

Aromatic polyisocyanates such as (n is an integer of 1 to 10); hexamethylene diisocyanate, 1.3 bis(isocyaner 1 to methyl) cyclohexane, 1 herimedyl hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate Ne 1~. 4.4'
Methylene bis(cyclohexyl isocyanate-1-), methyl cyclohexyl diisocyanate, 2.6 diisocyanate methyl caprolate.

CO ■ 0CN(l-CH2)4 C-C-0-(CH2su2
Aliphatic polyisocyanates such as NCO; silicone polyisocyanates such as CI-13CH3; aromatic acid chlorides such as isophthalic acid chloride, terephthalic acid chloride, trimellitic acid chloride; and aliphatic acid chlorides such as adipic acid chloride. can. These can be used alone or in combination of two or more. Particularly preferred are polyisocyanate compounds.

The combination of an amine group-containing compound and a polyfunctional compound is
Any combination may be used, but a particularly preferred example is one containing 10 to 80 mol%, preferably 20 to 70 mol%, of the silyl group of formula (2) in the produced polymer.

The solvent for the polyamine compound is preferably water or any liquid miscible with water, particularly water, methanol, ethanol, isopropanol, methylcellosolve, dioxane, ethylene glycol, diethylene glycol,
Triethylene glycol, dipropylene glycol, glycerin, or a mixed solvent of two or more thereof is preferred, and the amine is mixed with o, 19/100m+! More preferably, it is soluble at 0,597,100 mm or more.

The concentration of the amine group-containing compound is 1100 pp to 1
0 wt% 1: L< is 200 ppm to 2 wt%.

As the solvent for the polyfunctional compound, a solvent that forms an interface with at least one of the solvents for the amino group-containing compound is used, preferably an aliphatic hydrocarbon having 6 to 18 carbon atoms, or a halogenated solvent. It is a hydrocarbon, and specific examples thereof include n-hexane, n-peptane, n-octanecyclohexane, n-decane, n-tetradecane, hexadecene-1, carbon tetrachloride, trifluorotrichloroethylene, and the like. The concentration of polyfunctional compound is 20ρpm
~5W1%, preferably 50ppm ~3wt%.

Porous support materials include organic polymers such as polysulfone, polyethersulfone, cellulose acetate, cellulose, nylon 6, polyacrylonitrile, vinyl chloride, and polymethyl methacrylate, as well as glass porous materials, sintered metals, and ceramics. Can be mentioned.

The average pore diameter of the surface of such a porous support is 5 to 500n+
n 1 is preferably 7 to 1000 m. When it is smaller than 5 nm, the permeability is low, and when it is 500 nm or more, it is difficult to obtain a membrane with selectivity. The air permeation rate of this support at 25°C is 1X10-5 to 5ac/Cl.
1-8ec-cmHcJ, preferably 1xio-'
t~0', 5cc/Crl-5ec-cm l-1(
It is I. 1x 10-5 cc/ci-sec-
Below cmHQ, the transparency is low and impractical. Moreover, when it is 5 CC/cffl 6 sec-cmH (3 or more), the strength of the support decreases and it tends to become unusable.

The shape of such a support is a flat film.

It can be used in any form such as a hollow fiber shape or a tube shape. Any method may be used to impregnate the support with the amino group-containing compound or the polyfunctional compound, such as dipping, roll coating, spray coating, pressure injection, and vacuum inhalation. It is important to sufficiently impregnate the area near the surface of the body.

After impregnating a support with one solution of an amino group-containing compound or a polyfunctional compound, the excess solution adhering to the surface of the support was drained off, and then the other solution was soaked (4 compounds). When vapor is introduced, a reaction proceeds at the interface between the two liquids or at the interface between gas and liquid, forming a gas selectively permeable thin film.In this case, it is more preferable to avoid forming the interface between the two liquids. When forming the interface, any method such as immersion method or pressurization method can be used as a method for introducing the solution.

Such an interfacial reaction between the amino group-containing compound and the polyfunctional f)1 compound is carried out at 0 to 100 °C, preferably from 20 to 50 °C, for 5 seconds to 10 minutes at [σ], preferably from 10 seconds to 5 minutes.
Do this for minutes.

In this way, a composite membrane is obtained in which a thin film of selective gas permeation is formed on the surface of the support.Additionally, if necessary, the remaining solvent and amino acid-containing if compound,
By washing and drying the polyfunctional 1111↑11 compound, the gas selective permeation +1 composite membrane 19 of the present invention is obtained.

Gas selection I door permeation (the thickness of the thin film to the right of 11 is 5 parts m ~ 5
71 m, preferably 7 parts m to 1 μm, particularly preferably 10 parts m to 300 nm.

Effects The gas permeable membrane for gas separation of the present invention can be used to separate various gases by utilizing its excellent permeation amount per unit volume and excellent selectivity. For example, it can be incorporated into equipment that condenses oxygen from air, used in combustion furnaces, engines, etc. to improve combustion efficiency, and used as a treatment device for people with respiratory disorders.In industrial applications, it can also be used to separate various gases such as hydrogen and carbon monoxide. It can be done efficiently.

The present invention will be described below with reference to Examples, but the present invention is not limited thereto.

In the examples, "'part °'" is indicated.

Reference Example 1 (Production method of polysulfone hollow porous support) 20 parts of polysulfone (Nissan Chemical, Udel p3500), N-
Prepare a solution consisting of 5 parts of methyl-2-pyrrolidone, 3 parts of lithium chloride and 20 parts of 2-methoxyethanol,
Using water as the core liquid at 30°C, the above solution was discharged from circular Surin 1~, and immersed in water at 25°C to solidify.
! Ta.

Thus, a polysulfone hollow porous support with an outer diameter of 100 Il and an inner diameter of 500 uTr was obtained. This hollow support was packed into a pipe made of polycarbonate 1, and both ends were solidified with an adhesive to obtain a hollow fiber membrane module. The amount of air that permeates through this hollow fiber membrane at 25°C during drying is 1 x 1O-2 (C
C(STP)/cd-3eC-cmHq). This is an appropriate value for gas permeation f].

Reference Example 2 (Production method of non-woven fabric reinforced polysulfone porous membrane) Dacron 1 non-woven fabric ((It
7! +80!7/rrj, ) was fixed on a glass plate. Next, polysulfone 12.5w was applied on the nonwoven fabric.
t%, Methyl Cellsolve 12, 5W t%, and the balance dimethylformamide to a thickness of approximately 0.2 μm.
A non-woven reinforced porous polysulfone membrane was prepared by gelling the polysulfone layer in a water bath at room temperature.

The porous polysulfone layer obtained by this method has a thickness of about 40 to 70μ, has an asymmetric structure, and has a large number of micropores of about 50 to 600 pores remaining on the surface. Observed by micrograph.

In addition, these porous substrates have an air permeation rate of 5 x 10' to 1 x 10' cc/7-sec -c at 25°C.
It was mHg.

Example 1 2-aminoethylaminomethyltrimethylsilane 4.2
After dissolving 1 part in 50 parts of dimethylacetamide, 7.5 parts of diphenylmethane diisocyanate was added at room temperature, stirred for 3 hours, defoamed, cast on a Teflon plate, and dried in a hot air dryer at 150°C for 2 hours. It was dried to obtain a film with a thickness of 24 μm. Table 1 shows the permeation characteristics of this membrane.

Example 2 6.5 parts of 3-(2-amine ethyl)aminopropylheptamethyltrisiloxane was dissolved in 50 parts of dimethylacetamide, followed by 5 parts of diphenylmethane diisocyanate.
, 4 parts were added and the procedure was repeated in the same manner as in Example 1 to obtain a film with a thickness of 30 μm. The performance of this membrane is shown in Table 1.

(Leaving space below) Table 1 23-Example 3 A 0.1 wt% ethylene glycol solution of 3-(2-aminoethylaminopropyl)tris(trimethylsiloxy)silane was applied to the inner surface of the hollow fiber support shown in Reference Example 1. was introduced and maintained at a pressure of I Kg/ci for 1 minute. Next, after draining the residual liquid inside with nitrogen gas, a 250 ppm xadecene solution of diphenylmethane diisocyanate-1 was introduced at a linear velocity of 1 m/min, and the mixture was heated for 3 minutes.
The reaction was carried out at 5°C. Thereafter, the membrane was washed with running water for 10 minutes and then thoroughly air-dried to obtain a hollow fiber composite membrane. Table 2 shows the transmission performance of this crotch.

Example 4 The flat membrane support shown in Reference Example 2 was immersed in a 5 wt % ethylene glycol solution of 3-(2-amineethylaminopropyl)hebutamethyltrisiloxane for 10 minutes. Next, the liquid was drained using a rubber roller, and the sample was immersed in a 0.1 wt % solution of toluylene diisocyanate for 1 minute to react.

The composite membrane was then washed in running water for one day and then air-dried to obtain a composite membrane. The performance of this membrane is shown in Table 2.

Example 5 ]-1 l 82N(E-C[-12+2N(-CH2+2NmoCH
2te 38i [0-3i mo CH3h] 3's 0.1wt
% propylene glycol solution was injected into the hollow fiber support in the same manner as in Example 3, a 30ppm octadecene solution of isophorone diisocyanate was introduced into the inner surface of the hollow fiber at a linear velocity of 1 m/n+in, and reacted for 3 minutes at 25°C. Ta. Then, it was washed under running water for one day and thoroughly air-dried to obtain a composite membrane. The performance of this membrane is shown in Table 2.

Example 6 A 0.15 wt% ethylene glycol solution of dibutylmethyl-3-(4-piperidylmethylaminopropyl)silane was injected into the support in the same manner as in Example 3, and then a hexadecene solution of 500 ppm of xylylene diisocyanate and Example 3 were added. The composite membrane was prepared in the same manner as above by reacting, washing with water, and air drying.

The performance of this membrane is shown in Table 2.

(Margin below) Table 2

Claims (1)

[Scope of Claims] At least 50 mol% of all polyamine components has the following formula (1
) and/or (2) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・(1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・(2) [However, in the formula A is an a+b-valent or c+d-valent aliphatic hydrocarbon group, aromatic hydrocarbon group, or organosilyl group, B is an alkylene group or phenylene group having 10 or less carbon atoms, and R_0 is a hydrogen atom, and 1 carbon atom. It is an alkylene group having 1 to 6 carbon atoms that is also bonded to an alkyl group of ~6 or A to form a ring with ▲ ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ , where a is 0 or more, b is 1 or more, a+b is 2 or more, c is 2 or more, d is an integer of 1 or more, R_1, R_2, R
Each of _3 is independently an alkyl group or phenyl group having 1 to 10 carbon atoms, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼ ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (R_4～R_1_
1 represents the same or different alkyl group having 1 to 6 carbon atoms, and n
represents an integer greater than or equal to 1. ). a polyamine component which is an amino compound having at least two primary and/or secondary amino groups; and a crosslinking agent component which is a polyfunctional compound having at least two functional groups capable of reacting with amino groups. A gas selectively permeable membrane formed from a polymer obtained by the reaction of