JP2015029980A - Carbon dioxide separation material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carbon dioxide separation material excellent in selective separation capacity of carbon dioxide and production cost, and having a longer lifetime, and to provide a carbon dioxide separation membrane formed of the separation material.SOLUTION: There is provided a homopolymer or a copolymer having a cis-type double bond in a main chain and formed from propiolic acid shown by formula (I) or its derivative, or a carbon dioxide separation material comprising a polymer blend thereof (n is an integer of 10-100,000, and R is a univalent hydrocarbon group including at least one oxygen atom in a carbon-carbon bond).

Description

The present invention relates to a carbon dioxide separator, and more particularly, a carbon dioxide separator comprising a homopolymer, a copolymer, or a blend thereof having a cis-type double bond in the main chain formed from propiolic acid or a derivative thereof. And a carbon dioxide separation membrane formed from the separation material.

In recent years, utilization of various polymer materials has been studied for separation and purification of carbon dioxide from exhaust gas of thermal power generation, pyrolysis gas of biomass, or off-gas of oil fields. For example, poly-substituted acetylenes are known to have unique properties in their structure, in particular, they have a rigid main chain structure compared to vinyl polymers and high gas permeation performance due to the presence of bulky substituents. Is known (Non-Patent Document 1).

For example, poly-substituted acetylenes such as poly (diphenylacetylene) are known to have high material permeability, selective permeability, and excellent thermal stability (Patent Document 1). However, in these poly-substituted acetylenes obtained using tantalum pentachloride as the catalyst and tetrabutyltin as the cocatalyst, the geometric isomerism and higher order details of the resulting polymer and the permeation and separation performance of carbon dioxide are obtained. Is unknown. On the other hand, from the polymerization reaction mechanism, it is presumed that a polymer in which a cis type and a trans type are mixed contains a lot of amorphous substances (Non-patent Document 2). Such poly-substituted acetylenes are disadvantageous in that a distribution occurs in the size and volume of molecular gaps that contribute to gas permeability, and high selective permeation performance is exhibited. Moreover, the property may change over time due to contact with gas molecules involved in permeation. Furthermore, it is difficult from the production cost to synthesize industrially a large amount of poly (diphenylacetylene) s having a complicated structure.

When a substituted acetylene such as p-methylphenylacetylene is polymerized using a rhodium (Rh) complex as a polymerization catalyst, the polymerization proceeds in a stereoregular manner, and the double bond of the main chain is a cis-type polysubstituted acetylene. Is known to be obtained (Non-patent Document 3). The cis-type poly-substituted acetylene is formed into a helical structure in which the double bond of the main chain thus obtained is a cis type. Further, a gas separation comprising a helical substituted polyacetylene structure in which a Rh catalyst having a thiol group is immobilized on a gold substrate by a chemical bond, and a polyacetylene having a cis-type polyacetylene having a main chain double bond arranged vertically on the substrate. A membrane is known (Patent Document 2). Orienting molecules with a helical structure in one direction is considered to be one means for effectively utilizing the function. However, in such a structure whose one surface is a metal substrate, it is presumed that it is difficult for gas molecules to permeate perpendicularly to the film surface. It is known that a very small gas molecule such as hydrogen dissolves slightly against a metal such as Pd, but if it is a gas molecule having a size of about carbon dioxide, it can penetrate the gold substrate. It is even more difficult. Further, it is difficult to peel off the poly-substituted acetylene chemically bonded on the gold substrate from the substrate without destroying the structure. Furthermore, it is extremely difficult to industrially manufacture a structure manufactured through such a complicated process in large quantities and at low cost.

［式（Ｉ）中、ｎは１０〜１００，０００の整数である。Ｒは置換基を有していてもよい炭素数１〜１０のアルキル基、置換基を有していてもよい炭素数６〜１４のアリール基、炭素数４〜７の複素環基、Ｍ（式中、Ｍは水素原子または１価の金属を表す）のいずれかを表す］で表されるプロピオール酸又はその誘導体から形成される主鎖の二重結合がシス型の重合体からなる二酸化炭素吸着材を出願した（特許文献３）。しかし、該吸着材を分離膜にした際の二酸化炭素の透過性能については記載がなく不明である。 In order to solve these problems, the inventors of the present application already have the general formula (I).

[In formula (I), n is an integer of 10-100,000. R is an optionally substituted alkyl group having 1 to 10 carbon atoms, an optionally substituted aryl group having 6 to 14 carbon atoms, a heterocyclic group having 4 to 7 carbon atoms, M ( In the formula, M represents either a hydrogen atom or a monovalent metal)]. Carbon dioxide comprising a cis-type polymer in which the main chain double bond formed from propiolic acid or a derivative thereof An application was made for an adsorbent (Patent Document 3). However, the carbon dioxide permeation performance when the adsorbent is used as a separation membrane is not described and is unknown.

JP 2002-322293 A JP 2008-2222796 A JP 2010-207787 A

T. T. et al. Masuda, et. al. , J .; Am. Chem. Soc. , Vol. 105, p. 7473-7474, (1983) Toshio Masuda et al., Synthetic Organic Chemistry, Vol. 43, No. 8, p. 744-752 (1985) Tabata Masayoshi et al., Polymer, Vol. 55, No. 12, p. 938-941 (2006)

The present invention not only has a very good balance between the ability to selectively permeate and separate carbon dioxide and the manufacturing cost, but also has a greater toughness, so it withstands repeated use and therefore has a longer lifetime. A separation material and a carbon dioxide separation membrane formed from the separation material are provided.

The present inventors tried various studies to solve the above problems. First, the present inventors tried to produce a carbon dioxide separation material, for example, a carbon dioxide separation membrane, using the polymer represented by the general formula (I) in Patent Document 3. However, although the polymer is excellent in the ability to selectively adsorb carbon dioxide, it has not been sufficient in terms of the ability to selectively permeate and separate carbon dioxide in the mixed gas. Further, depending on the structure, there are some which are difficult to produce the carbon dioxide separation membrane itself without being dissolved in the solvent. In addition, the yield of the polymer is relatively small, resulting in high cost of the carbon dioxide separator. Therefore, the present inventors have further studied and improved the polymer of the general formula (I) in Patent Document 3 described above, and as a group represented by R in the general formula (I), the carbon-carbon bond If a monovalent hydrocarbon group containing at least one oxygen atom is used, the carbon dioxide separating material formed from the polymer has an extremely good ability to selectively permeate and separate carbon dioxide. Not only that, the yield of the polymer is higher, and in addition, it has been found that it has a longer life when used as a carbon dioxide separation membrane or the like, thereby completing the present invention. Patent Document 3 describes a remarkably large number of groups as the group represented by R in the general formula (I). However, for all of these groups, the effect as a carbon dioxide adsorbent is not demonstrated in the examples. Moreover, the Example of patent document 3 is only as a carbon dioxide adsorbent, and the effect as a carbon dioxide separating material, that is, the ability to selectively permeate and separate carbon dioxide in a mixed gas is not studied at all. Not.

（式（Ｉ）中、ｎは１０〜１００，０００の整数を示し、Ｒは、炭素・炭素結合中に少なくとも１個の酸素原子を含む一価の炭化水素基を示す。）
で示されるプロピオール酸又はその誘導体から形成される主鎖の二重結合がシス型のホモポリマー若しくはコポリマー、又は、これらのポリマーブレンドからなる二酸化炭素分離材である。 That is, the present invention provides (1) the following formula (I)

(In formula (I), n represents an integer of 10 to 100,000, and R represents a monovalent hydrocarbon group containing at least one oxygen atom in the carbon-carbon bond.)
A carbon dioxide separator comprising a homopolymer or copolymer having a cis-type double bond in the main chain formed from propiolic acid or a derivative thereof, or a polymer blend thereof.

As a preferred embodiment,
(2) R in the above formula (I) represents a chain or cyclic monovalent aliphatic hydrocarbon group containing at least one oxygen atom in the carbon-carbon bond, Carbon dioxide separator,
(3) R in the above formula (I) is selected from the group consisting of an alkyl group having 2 to 15 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, and a combination thereof. The group of (1), which contains at least one oxygen atom in its carbon-carbon bond,
(4) R in the formula (I) is selected from the group consisting of an alkyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, and a combination thereof, wherein The group of (1), which contains at least one oxygen atom in its carbon-carbon bond,
(5) R in the above formula (I) is selected from the group consisting of an alkyl group having 2 to 7 carbon atoms, a cycloalkyl group having 3 to 5 carbon atoms, and a combination thereof, wherein The group of (1), which contains at least one oxygen atom in its carbon-carbon bond,
(6) R in the above formula (I) is represented by the formula —CHR ¹ —CHR ¹ —O—R ² , wherein each R ¹ independently represents a hydrogen atom and a carbon number of 1 to 2 The carbon dioxide separator according to (1) above, wherein R ² is selected from alkyl groups having 1 to 5 carbon atoms,
(7) R in the formula (I) is represented by the formula —CHR ¹ —CHR ¹ —O—R ² , wherein each R ¹ is independently a group consisting of a hydrogen atom and a methyl group. The carbon dioxide separator according to (1), wherein R ² is selected from alkyl groups having 1 to 3 carbon atoms,
(8) The description in (1) above, wherein R in the formula (I) is selected from the group consisting of a methoxyethyl group, an ethoxyethyl group, a 1-methoxy-2-propyl group, and a 1-ethoxy-2-propyl group. Carbon dioxide separator,
(9) The carbon dioxide separator according to (1), wherein R in the formula (I) is a methoxyethyl group or an ethoxyethyl group,
(10) The carbon dioxide separator according to any one of (1) to (9), wherein n represents an integer of 100 to 5,000,
(11) The above (1) to (1) for separation of carbon dioxide in helium, hydrogen, oxygen, nitrogen, carbon monoxide, hydrocarbon having 1 to 5 carbon atoms, nitrogen oxide, sulfur oxide or a mixture thereof. 10) The carbon dioxide separator according to any one of
(12) In any one of the above (1) to (10), which is for separating carbon dioxide in helium, hydrogen, oxygen, nitrogen, carbon monoxide, hydrocarbon having 1 to 5 carbon atoms, or a mixture thereof. The carbon dioxide separator as described,
(13) A homopolymer or copolymer having a cis-type double bond in the main chain formed from propiolic acid or a derivative thereof represented by the above formula (I) is polymerized using a group 8-10 metal compound as a catalyst. The carbon dioxide separator according to any one of (1) to (12) above,
(14) The separation membrane which consists of a carbon dioxide separation material as described in any one of said (1)-(13) can be mentioned.

In the carbon dioxide separator composed of a homopolymer or copolymer represented by the formula (I) or a polymer blend thereof according to the present invention, R in the formula (I) preferably contains at least one oxygen atom. Is contained in the carbon-carbon bond, and therefore has an excellent ability to selectively permeate and separate carbon dioxide in the mixed gas. Therefore, according to the separation membrane manufactured from these carbon dioxide separation materials, carbon dioxide can permeate and be purified by remarkably good selectivity. In addition, since the homopolymer and copolymer represented by the formula (I) can be produced with a relatively high yield, the carbon dioxide separation material can be produced at a lower cost. As described above, the carbon dioxide separation material of the present invention and the carbon dioxide separation membrane formed therefrom are extremely excellent in the balance between the ability to selectively permeate and separate carbon dioxide and the production cost. Furthermore, the carbon dioxide separation material of the present invention and the carbon dioxide separation membrane formed therefrom have a greater toughness and therefore withstand repeated use and thus have a longer life.

The carbon dioxide separator of the present invention is a homopolymer or copolymer in which the double bond of the main chain formed from propiolic acid represented by the above formula (I) or a derivative thereof is cis type (hereinafter simply referred to as “polymer”). Or a blend of these polymers. The polymer contains crystals in which the double bond of the main chain is a cis type and forms a helical structure, and these helical structures are aggregated. Here, the homopolymer is one in which Rs in the formula (I) are all composed of the same monomer, and the copolymer is one in which Rs in the formula (I) are different.

The average degree of polymerization n in the above formula (I) is an integer of 10 to 100,000, preferably 100 to 100,000, more preferably 100 to 5,000. By setting n to 10 or more, the mechanical strength of the molded product obtained from the polymer becomes more excellent, and by setting it to 100 or more, the moldability is more preferable. On the other hand, in consideration of the production cost and molding cost of the polymer, n is preferably 10,000 or less. The number average molecular weight of the polymer having n of 10 to 100,000 is about 1,000 to 30,000,000. Under the reaction (polymerization) conditions described in detail below, when the reaction temperature is lowered, the reaction time is shortened, or the concentration of propiolic acid or its derivative is lowered, the number average molecular weight of the resulting polymer is lowered. Here, the average degree of polymerization n of the polymer can be calculated based on a calibration curve obtained from a polystyrene standard substance, for example, by measurement using gel permeation chromatography (GPC). The primary structure of the polymer can be measured, for example, by ¹ H-NMR.

In the above formula (I), R preferably represents a monovalent hydrocarbon group containing at least one oxygen atom in the carbon / carbon bond, preferably at least one oxygen in the carbon / carbon bond. A chain or cyclic monovalent aliphatic hydrocarbon group containing an atom is shown. Of course, the chain | strand or cyclic | annular monovalent | monohydric aliphatic hydrocarbon group may be combined. R preferably represents an alkyl group having 2 to 15 carbon atoms, more preferably 2 to 10 carbon atoms, still more preferably 2 to 7 carbon atoms, and preferably 3 to 12 carbon atoms, more preferably 3 carbon atoms. -8, more preferably a cycloalkyl group having 3 to 5 carbon atoms, and a combination of these alkyl groups and cycloalkyl groups. Here, the above-mentioned alkyl group, cycloalkyl group, and group of these combinations are preferably at least 1, preferably 1 to 3, more preferably 1 to 2, more preferably in the carbon-carbon bond. Preferably it contains one oxygen atom.

で表される基等が挙げられる。これらのうち、上記式（Ｉ）におけるＲとしては、式−ＣＨＲ^１−ＣＨＲ^１−Ｏ−Ｒ^２で示される基が好ましい。ここで、各Ｒ^１は、夫々独立して、水素原子及び炭素数１〜２のアルキル基、好ましくは、水素原子及びメチル基より成る群から選ばれ、Ｒ^２は、炭素数１〜５のアルキル基、好ましくは炭素数１〜３のアルキル基から選ばれる。上記式（Ｉ）におけるＲとしては、より好ましくは、メトキシエチル基、エトキシエチル基、１−メトキシ−２−プロピル基及び１−エトキシ−２−プロピル基より成る群から選ばれる。 In R in the formula (I), examples of the alkyl group that contains at least one oxygen atom in the carbon-carbon bond include a methoxyethyl group, an ethoxyethyl group, and 1-methoxy-2. -Propyl group, 1-ethoxy-2-propyl group, 1- (n-propoxy) -2-propyl group, n-propoxymethyl group, n-propoxyethyl group, 2-propoxymethyl group, 2-propoxyethyl group, n-butoxymethyl group, n-butoxyethyl group, isobutoxymethyl group, isobutoxyethyl group, 1- (n-butoxy) -2-propyl group, 1-isobutoxy-2-propyl group, methoxy n-propyl group, Methoxy n-butyl group, methoxy n-pentyl group, and the following formula

The group etc. which are represented by these are mentioned. Of these, R in the formula (I) is preferably a group represented by the formula —CHR ¹ —CHR ¹ —O—R ² . Here, each R ¹ is independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 2 carbon atoms, preferably a hydrogen atom and a methyl group, and R ² has 1 to 5 carbon atoms. The alkyl group is preferably selected from alkyl groups having 1 to 3 carbon atoms. R in the above formula (I) is more preferably selected from the group consisting of a methoxyethyl group, an ethoxyethyl group, a 1-methoxy-2-propyl group and a 1-ethoxy-2-propyl group.

In R in the above formula (I), examples of the cycloalkyl group that includes at least one oxygen atom in the carbon-carbon bond include a tetrahydropyranyl group, a dioxanyl group, a trioxanyl group, A dioxiranyl group, an oxiranyl group, a dioxetanyl group, an oxetanyl group, etc. are mentioned. In addition, in R in the above formula (I), a group which is a combination of the above alkyl group and cycloalkyl group and includes at least one oxygen atom in the carbon-carbon bond, for example, ^{R 2} groups of formula -CHR ¹ -CHR ^{1 -O-R 2} are those which are the above cycloalkyl group, ^or a a group represented by ^{-R 2 -O-CHR 1 -CHR 1} 2 R ² is the above cycloalkyl group.

The polymer represented by the above formula (I) is synthesized by a reaction represented by the following chemical reaction formula.

In the present invention, the polymerization of propiolic acid represented by the above formula (I) or a derivative thereof is usually carried out in an organic solvent. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropyl alcohol, isobutyl alcohol, isopentyl alcohol, and neopentyl alcohol; dimethyl ether, ethyl methyl ether, diethyl ether, dipropyl ether, butyl methyl ether, tert-butyl methyl Ethers such as ether, dibutyl ether, ethyl phenyl ether, diphenyl ether, tetrahydrofuran, 1,4-dioxane; ketones such as acetone, ethyl methyl ketone, methyl propyl ketone, diethyl ketone, ethyl propyl ketone, dipropyl ketone; heptane, pentane, Hydrocarbons such as hexane, octane, cyclohexane; methylene chloride, chloroform, carbon tetrachloride, 1,2-dichloroethane, 1,1-di Roroetan, trichloroethane, halogenated hydrocarbons such as chlorobenzene; acetonitrile, propionitrile, nitriles such as benzonitrile; benzene, toluene, xylene, mesitylene, and aromatic hydrocarbons such as ethylbenzene and the like. Among these organic solvents, it is preferable to use a highly polar organic solvent such as alcohol from the viewpoint of reaction rate. These organic solvents may be used alone or in combination of two or more.

When the organic solvent is used, the amount of the organic solvent used is not particularly limited, but is preferably 1 to 95% by mass, and more preferably 70 to 95% in the entire propiolic acid or derivative thereof and the organic solvent mixed solution. % By mass. By making the amount of the organic solvent used 1% by mass or more, the viscosity of the mixed solution can be lowered to enable efficient stirring, and by making it 95% by mass or less, a practical reaction rate can be maintained. it can.

In the present invention, when polymerizing propiolic acid or a derivative thereof, it is preferable to use a catalyst in order to facilitate the reaction. As the catalyst, a group 8-10 metal compound is preferably used. Examples of preferably used Group 8-10 metal compounds include rhodium complexes, palladium complexes, iridium complexes, platinum complexes, ruthenium complexes, and the like.

Examples of the rhodium complex include chlorotris (triphenylphosphine) rhodium, acetylacetonatobis (ethylene) rhodium, acetylacetonatobis (cyclooctene) rhodium, acetylacetonato (1,5-cyclooctadiene) rhodium, (1 , 5-cyclooctadiene) bis (triphenylphosphine) rhodium hexafluorophosphate, (norbornadiene) tris (triphenylphosphine) rhodium hexafluorophosphate, bis (1,5-cyclooctadiene) rhodium trifluoromethanesulfonate, bis (norbornadiene) ) Rhodium tetrafluoroborate, chlorobis (ethylene) rhodium dimer, chlorobis (cyclooctene) rhodium dimer, chloro (1,5-cyclooctadiene) Ethidium dimer, chloro (norbornadiene) rhodium dimer, chloro (dicyclopentadienyl) rhodium dimer, chloro (tetrafluorobenzoylene Bale Ren) rhodium dimer, and the like.

Examples of the palladium complex include dichloro (1,5-cyclooctadiene) palladium. Examples of iridium complexes include acetylacetonato (1,5-cyclooctadiene) iridium, bis (1,5-cyclooctadiene) iridium tetrafluoroborate, chlorobis (cyclooctene) iridium dimer, chloro (1,5-cycloocta And diene) iridium dimer. Examples of the platinum complex include dichloro (1,5-cyclooctadiene) platinum and dichloro (dicyclopentadienyl) platinum. Examples of the ruthenium complex include a second generation Grubbs-Hoveyda catalyst.

Of these, chloro (1,5-cyclooctadiene) rhodium dimer, chloro (norbornadiene) rhodium dimer, and chloro (tetrafluorobenzovalerene) rhodium dimer are preferable. From the viewpoint of polymerization activity and industrial availability, chloro ( Norbornadiene) rhodium dimer is more preferred.

The amount of the catalyst used is preferably in the range of 0.000001 to 10 mol in terms of metal atom per liter of the reaction (polymerization) mixture (propiolic acid or derivative thereof and the organic solvent), and 0.0001 to 1 mol. The range of is more preferable. If the amount of the catalyst used is less than 0.000001 mol per liter of the reaction (polymerization) mixture in terms of metal atoms, the reaction rate tends to be extremely slow, and even if it exceeds 10 mol, an effect commensurate with it is obtained. It only increases the cost of the catalyst.

In the present invention, the reaction temperature when polymerizing propiolic acid or a derivative thereof is preferably in the range of −60 to 100 ° C., more preferably in the range of 0 to 40 ° C. By setting the reaction temperature to −60 ° C. or higher, the reaction proceeds within an appropriate time. By setting the reaction temperature to 100 ° C. or lower, side reactions such as isomerization from cis form to trans form can be suppressed. The reaction time in the polymerization of propiolic acid or a derivative thereof is usually in the range of 1 minute to 48 hours, and preferably in the range of 0.5 to 10 hours from the viewpoint of production efficiency. Usually, it is preferable to carry out the reaction for a long time when the reaction temperature is low and for a short time when the reaction temperature is high. The reaction in the polymerization of propiolic acid or a derivative thereof is usually performed under normal pressure.

The reaction is usually carried out according to the following procedure. First, a mixed solution 1 in which propiolic acid or a derivative thereof is dissolved in an organic solvent is prepared. Separately, a mixed solution 2 in which a catalyst such as a group 8-10 metal compound is dissolved in the same organic solvent is prepared. Subsequently, the liquid mixture 1 and the liquid mixture 2 are mixed, stirred while being kept at a predetermined reaction temperature, and reacted for a predetermined time to obtain a reaction liquid containing a polymer.

In this polymerization, it is preferable to use a poor solvent having low solubility in the resulting polymer, for example, alcohol, acetonitrile, ether, acetate, acetone, water or n-hexane. Alternatively, the propiolic acid or a derivative thereof may be polymerized at room temperature for several hours using a mixed solvent such as alcohol, toluene, chloroform, dimethylformamide, dimethyl sulfoxide, ionic liquid or supercritical liquid carbon dioxide. Since the polymer polymerized in this way is aggregated and precipitated in a solvent, it can be obtained in the form of a porous material or powder.

In the present invention, the polymer can be isolated and purified by a general technique from the reaction solution obtained in the polymerization step of propiolic acid or its derivative. For example, the polymer can be obtained by adding the obtained reaction solution to a poor solvent such as methanol, water, or n-hexane to precipitate the polymer, separating it by filtration, and drying it. If necessary, the polymer can be subjected to reprecipitation treatment, or the remaining metal compound and low molecular weight components can be removed using a poor solvent and a Soxhlet extractor or the like.

The shape of the carbon dioxide separator of the present invention is not particularly limited and may be any molded body that can be produced using a polymer. For example, a film, a sheet, a plate, a pipe, a tube, a rod-shaped body, a granular body, and a powder , Various deformed shapes, fibers, hollow fibers, woven fabrics, knitted fabrics, non-woven fabrics and the like. In particular, when this material is used as a separation membrane, it is preferably a film from the viewpoint of gas molecule permeability, selectivity, and processing efficiency, and from the viewpoint of processing efficiency, it is coated with a hollow fiber or the polymer. More preferably, it is a molded body or a hollow fiber.

When the polymer used as the carbon dioxide separator of the present invention is used in the form of a film, it can be used as a film capable of selectively permeating and separating carbon dioxide. As a method for forming the film, a liquid organic polymer composition is prepared by dissolving the carbon dioxide separating material of the present invention in an appropriate solvent, and the liquid organic polymer composition is used as a peelable substrate or support. It can manufacture by employ | adopting the method of drying and removing a solvent after apply | coating on a body. Examples of the solvent for dissolving the carbon dioxide separator of the present invention include chloroform, dichloromethane, tetrahydrofuran, toluene and the like.

The method of applying the carbon dioxide separator of the present invention to the releasable substrate or support is not particularly limited, and any of the conventionally known coating methods using a liquid coating material can be used. Can be adopted. For example, dip coating method, spray coating method, spinner coating method, bead coating method, wire bar coating method, blade coating method, roller coating method, curtain coating method, slit die coater method, gravure coater method, slit reverse coater method, micro Coating methods such as a gravure method and a comma coater method can be employed.

The carbon dioxide separator of the present invention can be used as it is, but if necessary, natural or synthetic such as cellulose acetate, polyamide, polyester, polycarbonate, polysulfone, polyethersulfone, polyolefin, polytetrafluoroethylene derivative or paper It may be combined with fibers or inorganic fibers such as glass or alumina. Examples of the shape of the carbon dioxide separator include a bulk body, a woven fabric, a non-woven fabric, and a film.

The carbon dioxide separation material of the present invention is an antioxidant, an antifreezing agent, a pH adjuster, a concealing agent, a colorant, an oil agent, a flame retardant, and other similar materials, as long as it does not impair the effects of the present invention. One or more additives of an infrared absorbing compound, an ultraviolet absorber, a color tone correcting agent, a dye, an antioxidant, and other special functional agents can be contained.

The carbon dioxide separator of the present invention comprising a polymer can selectively separate carbon dioxide mixed in various gases, but preferably helium, hydrogen, oxygen, nitrogen, carbon monoxide, carbon containing 1-5 hydrocarbons, nitrogen oxides _(NO X), sulfur oxides (SO _X) or mixtures thereof, in particular, helium, hydrogen, oxygen, nitrogen, carbon monoxide, hydrocarbons of 1 to 5 carbon atoms Alternatively, it is effective for selectively separating carbon dioxide mixed in the mixture.

In the following examples, the present invention will be described in more detail, but the present invention is not limited to these examples.

Analysis and evaluation in Examples and Comparative Examples were performed as follows.

(1) Molecular structure of polymer:
[Solution ¹ H-NMR]
When the obtained polymer was dissolved in chloroform, solution ¹ H-NMR (nuclear magnetic resonance) measurement was performed, and the structure was identified from the chemical shift value when tetramethylsilane (TMS) was used as an internal standard substance. .

<Analysis conditions>
Apparatus: 500 MHz superconducting nuclear magnetic resonance apparatus JEOL JNM-ECA500 (trademark, manufactured by JEOL Ltd.)
Solvent: Deuterated chloroform containing 0.03 v / v% TMS (manufactured by ISOTEC)
Concentration: 20 mg / ml Temperature: 20 ° C
Integration count: 32 times

[Solid state ¹³ C-NMR (CP / MAS method)]
When the obtained polymer was not dissolved in chloroform, solid ¹³ C-NMR (nuclear magnetic resonance) measurement was performed, and the structure was identified from the chemical shift value when adamantane was used as a reference substance.

<Analysis conditions>
Apparatus: 500 MHz superconducting nuclear magnetic resonance apparatus JNM-ECA500 (trademark, manufactured by JEOL Ltd.)
Temperature: 20 ° C
Integration count: 5,000 times

(2) Molecular weight measurement of polymer It measured using the gel permeation chromatography (GPC), and computed as a polystyrene conversion molecular weight. Details of the measurement conditions are shown below.

<Analysis conditions>
Apparatus: Gel permeation chromatography JASCO GPC-900 (trademark, manufactured by JASCO Corporation)
Column: Connect two Shodex K-806L (trademark, manufactured by Showa Denko KK) (column temperature: 40 ° C.)
Mobile phase: Chloroform (for high performance liquid chromatography) (genuine)
Flow rate: 1.0 ml / min Detector: RI
Filtration: filter concentration with a pore size of 0.45 μm: 0.5 mg / ml injection amount: 20 μL
Standard substance: polystyrene standard (Mw: 800 to 1,090,000)

(3) Gas permeation measurement <analysis conditions>
Apparatus: Gas permeability measuring apparatus K-315-01 (trademark, manufactured by Tsukubarika Seiki Co., Ltd.)
High pressure side pressure: 133.32 kPa (maximum value)
Pressure on the decompression side: 1333 Pa (maximum value)
Cell diameter: 20mm in diameter
Temperature: 25 ° C

Hereinafter, oxygen may be referred to as O ₂ , nitrogen as N ₂ , carbon dioxide as CO ₂ , and methane as CH ₄ .

Example 1
<Synthesis of poly (methoxyethyl propiolate)>
1.28 g (10.0 mmol) of methoxyethyl propiolate monomer was placed on one side of a U-shaped polymerization tube, 46 mg (0.1 mmol) of chloro (norbornadiene) rhodium dimer was placed on the other side, and 2.5 mL of dehydrated methanol purified by distillation Was added to each. After performing vacuum degassing in the system with a vacuum pump while cooling in liquid nitrogen, the U-type polymerization tube was shaken by hand for about 30 seconds so that the above two substances were well mixed in the system, Polymerization was carried out at 40 ° C. for 4 hours in a thermostatic shaker. 300 mL of methanol was put into a 500 mL beaker, and the reaction solution after completion of polymerization was taken into the beaker while washing the U-shaped polymerization tube with methanol. Stir for 10 minutes and then let stand until a precipitate is formed. Only the supernatant was removed by suction filtration, and 150 mL of methanol was added to the precipitate and stirred again for 10 minutes. The same operation was repeated twice and finally the precipitate was collected. The precipitate was dried under reduced pressure for 12 hours or more in a desiccator. About 0.95 g of polymer was obtained (yield: 74%).

As a result of dissolving the obtained polymer in deuterated chloroform and performing ¹ H-NMR measurement, 3.38 ppm (—OC H ₃ : 3H), 3.56 ppm (—C H ₂ OCH ₃ : 2H); 95 and 4.11 ppm (—COOC H ₂ —: 2H) and 6.89 ppm ( —H C =: 1H), respectively. Methoxyethyl propiolate) (R in formula (I) was confirmed to be —CH ₂ —CH ₂ —O—CH ₃ (methoxyethyl group)). The number average molecular weight of the obtained polymer was 130,000 [degree of polymerization≈1015].

<Gas permeation measurement of poly (methoxyethyl propiolate)>
50 mg of the obtained poly (methoxyethyl propiolate) was dissolved in 2 mL of dichloromethane, cast into a microporous membrane made of nitrocellulose (manufactured by MILLIPORE), and dried to form a film by a method of completely removing the solvent. For films coated with poly (methoxyethyl _propiolate), the pure gas permeability coefficient of _{CO 2, CH 4 (P CO2} , P CH4) measurements were performed. The results are shown in Table 1.

(Example 2)
<Synthesis of poly (ethoxyethyl propiolate)>
The synthesis was performed in the same manner as in Example 1 except that 1.42 g (10.0 mmol) of ethoxyethyl propiolate monomer was used instead of methoxyethyl propiolate monomer. About 1.07 g of polymer was obtained (yield: 75%).

The resulting polymer was dissolved in deuterated chloroform, as a result of the ¹ H-NMR _{measurement, 1.20ppm (-CH 2 C H 3} : 3H), 3.53ppm (-C H 2 OCH 2 CH 3: 2H _{), 3.59ppm (-OC H 2 CH} 3: 2H), 3.96 and _{4.12ppm (-COOC H 2 -: 2H} ), 6.84ppm (- H C =: 1H) peaks attributed respectively The main chain double bond is cis-type poly (ethoxyethylpropiolate) (in formula (I), R is —CH ₂ —CH ₂ —O—CH ₂ —CH ₃ (ethoxy Ethyl group)). The number average molecular weight of the obtained polymer was 130,000 [degree of polymerization≈915].

<Gas permeation measurement of poly (ethoxyethyl propiolate)>
A film was formed in the same manner as in Example 1 except that poly (ethoxyethylpropiolate) was used instead of poly (methoxyethylpropiolate) and toluene was used as a solvent. The film coated with poly (ethoxyethyl _propiolate), the pure gas permeability coefficient of _{CO 2, CH 4 (P CO2} , P CH4) measurements were performed. The results are shown in Table 1.

Example 3
<Synthesis of poly (1-methoxy-2-propylpropiolate)>
The synthesis was performed in the same manner as in Example 1 except that 1.42 g (10.0 mmol) of 1-methoxy-2-propylpropiolate monomer was used instead of methoxyethyl propiolate monomer. About 0.60 g of polymer was obtained (yield: 42%).

The obtained polymer was dissolved in deuterated chloroform and subjected to ¹ H-NMR measurement. As a result, 1.23 ppm (—OC H ₃ : 3H), 3.33 ppm (—CHC H ₃ —: 3H), 3.46 ppm _{(-C H 2 -OCH 3: 2H} ), 4.91ppm (-C H CH 3 -: 1H), 7.06ppm -: for had a peak attributed respectively (H C = 1H), mainly Poly (1-methoxy-2-propylpropiolate) in which the double bond of the chain is cis type [R in the formula (I) is —CH (CH ₃ ) —CH ₂ —O—CH ₃ (1-methoxy -2-propyl group). It was confirmed that The number average molecular weight of the obtained polymer was 70,000 [degree of polymerization≈492].

<Gas permeation measurement of poly (1-methoxy-2-propylpropiolate)>
A film was formed in the same manner as in Example 1 except that poly (1-methoxy-2-propylpropiolate) was used instead of poly (methoxyethylpropiolate) and toluene was used as a solvent. With respect to the film coated with poly (1-methoxy-2-propylpropiolate), the CO ₂ and CH ₄ pure gas permeability coefficients (P _CO2 and P _CH4 ) were measured. The results are shown in Table 1.

Example 4
<Synthesis of poly (1-ethoxy-2-propylpropiolate)>
The synthesis was performed in the same manner as in Example 1 except that 1.56 g (10.0 mmol) of 1-ethoxy-2-propylpropiolate monomer was used instead of methoxyethyl propiolate monomer. About 0.66 g of polymer was obtained (yield: 42%).

The resulting polymer was dissolved in deuterated chloroform, ¹ H-NMR measurement results of _{performing, 1.16ppm (-CH 2 -C H 3} : 3H), 1.24ppm (-OC H 2 -CH 3: 2H _{), 3.32ppm (-C H 2 -OCH} 2 CH 3: 2H), 3.50ppm (-CHC H 3 -: 3H), 4.88ppm (-C H CH 3 -: 1H), 7.00ppm ( -H C = 1H), respectively, so that the double bond of the main chain is cis-type poly (1-ethoxy-2-propylpropiolate) [R in the formula (I) Is —CH (CH ₃ ) —CH ₂ —O—CH ₂ —CH ₃ (1-ethoxy-2-propyl group). It was confirmed that The number average molecular weight of the obtained polymer was 110,000 [degree of polymerization≈704].

<Gas permeation measurement of poly (1-ethoxy-2-propylpropiolate)>
A film was formed in the same manner as in Example 1 except that poly (1-ethoxy-2-propylpropiolate) was used instead of poly (methoxyethylpropiolate) and toluene was used as a solvent. With respect to the film coated with poly (1-ethoxy-2-propylpropiolate), the pure gas permeation coefficients (P _CO2 and P _CH4 ) of CO ₂ and CH ₄ were measured. The results are shown in Table 1.

(Comparative Example 1)
<Synthesis of poly (methylpropiolate)>
The synthesis was performed in the same manner as in Example 1 except that 0.84 g (10.0 mmol) of methyl propiolate monomer was used instead of methoxyethyl propiolate monomer. About 0.59 g of polymer was obtained (yield: 70%).

Since the obtained polymer was insoluble in various organic solvents, solid ¹³ C-NMR measurement was performed by CP / MAS method. As a result, 52 ppm (—O C H ₃ ), 128 ppm (= C H— ), 134 ppm (= C- ), 164 ppm ( C = O), respectively, and the main chain double bond is cis-type poly (methylpropiolate) (in formula (I)) R in the formula is —CH ₃ (methyl group). The obtained polymer was insoluble in various organic solvents, and its number average molecular weight could not be calculated.

<Gas permeation measurement of poly (methylpropiolate)>
Since the obtained polymer, poly (methylpropiolate), was insoluble in various organic solvents, it could not be formed into a film. _Thus, the pure gas permeability coefficient of _{CO 2, CH 4 (P CO2} , P CH4) measurements were impossible.

(Comparative Example 2)
<Synthesis of poly (ethylpropiolate)>
The synthesis was performed in the same manner as in Example 1 except that 0.98 g (10.0 mmol) of ethyl propiolate monomer was used instead of methoxyethyl propiolate monomer. About 0.61 g of polymer was obtained (yield: 63%).

The resulting polymer was dissolved in deuterated chloroform, ¹ H-NMR measurement results of _{performing, 1.23ppm (-CH 2 C H 3} : 3H), 3.97ppm (-C H 2 CH 3: 2H), Each has a peak attributed to 6.86 ppm (—C H ═C—: 1 H), and the double bond of the main chain is cis-type poly (ethylpropiolate) [R in the formula (I) Is —CH ₂ —CH ₃ (ethyl group). )]. The number average molecular weight of the obtained polymer was 22,000 [degree of polymerization≈224].

<Gas permeation measurement of poly (ethyl propiolate)>
A film was formed in the same manner as in Example 1 except that poly (ethylpropiolate) was used instead of poly (methoxyethylpropiolate) and chloroform was used as a solvent. For films coated with poly (ethyl _propiolate), the pure gas permeability coefficient of _{CO 2, CH 4 (P CO2} , P CH4) measurements were performed. The results are shown in Table 1.

(Comparative Example 3)
<Synthesis of poly (n-butylpropiolate)>
The synthesis was performed in the same manner as in Example 1 except that 1.26 g (10.0 mmol) of n-butylpropiolate monomer was used instead of methoxyethyl propiolate monomer. About 0.44 g of polymer was obtained (yield: 35%).

The resulting polymer was dissolved in deuterated chloroform, ¹ H-NMR measurement results of _{performing, 0.93ppm (-CH 2 C H 3} : 3H), 1.38ppm (-C H 2 CH 3: 2H), _{1.59ppm (-CH 2 -C H 2 -CH} 2 -: 2H), 3.76~3.98ppm (-O-C H 2 -CH 2 -: 2H), 6.85ppm (-C H = C -: has a peak attributed respectively 1H), of the main chain double bonds of cis poly (n- butyl propiolate) [R in formula _(I), -CH 2 -CH is ₂ -CH ₂ -CH ₃ (n- butyl). It was confirmed that The number average molecular weight of the obtained polymer was 32,000 [degree of polymerization≈254].

<Gas permeation measurement of poly (n-butylpropiolate)>
A film was formed in the same manner as in Example 1 except that poly (n-butylpropiolate) was used instead of poly (methoxyethylpropiolate). For films coated with poly (n- butyl _propiolate), the pure gas permeability coefficient of _{CO 2, CH 4 (P CO2} , P CH4) was measured. The results are shown in Table 1.

表１中、透過係数の単位ｂａｒｒｅｒ（バーラー）は、１×１０^−１０ｃｍ^３（ＳＴＰ）・ｃｍ・ｃｍ^−２・ｓ^−１・ｃｍＨｇ^−１を表す。

In Table 1, the transmission coefficient unit barrer represents 1 × 10 ⁻¹⁰ cm ³ (STP) · cm · cm ⁻² · s ⁻¹ · cmHg ⁻¹ .

From the results shown in Table 1, in Examples 1 to 4, carbon dioxide is selected because the ratio of the permeability coefficient of CO _{2 to} CH ₄ is high and the yield of the raw material (the obtained polymer) is also high. It was found that a carbon dioxide separation membrane having an extremely good balance between the property of being permeated and separated and the production cost was obtained. In addition, since the raw material has a high degree of polymerization, it has been found that when a carbon dioxide separation membrane or the like is formed, the membrane is flexible and difficult to break and can withstand repeated use for a long time. . For the carbon dioxide separation membrane comprising the film coated with poly (methoxyethylpropiolate) of Example 1, the above-mentioned permeability coefficient ratio showed a lower value than those of the other examples, but on the other hand, the raw material The poly (methoxyethylpropiolate) yield is significantly high, so that the effect of the present invention, that is, the property of selectively permeating and separating carbon dioxide and the balance of production cost are not impaired. Furthermore, the degree of polymerization of the raw material was remarkably high, and it was found that the carbon dioxide separation membrane was excellent overall. For the carbon dioxide separation membrane comprising the film coated with poly (ethoxyethylpropiolate) of Example 2, not only the above permeation coefficient ratio was remarkably high, but also the raw material poly (ethoxyethylpropiolate). The yield was remarkably high, the balance was very good, and the polymerization degree of the raw material was remarkably high, which proved to be an extremely excellent carbon dioxide separation membrane. The carbon dioxide separation membranes comprising the films coated with poly (1-methoxy-2-propylpropiolate) and poly (1-ethoxy-2-propylpropiolate) of Examples 3 and 4 are both highly permeable. It shows a coefficient ratio, and the yield of the raw material is relatively high, has a good balance, and further has a high degree of polymerization of the raw material, indicating that it is an excellent carbon dioxide separation membrane. .

On the other hand, the poly (methylpropiolate) of Comparative Example 1 was obtained at a relatively high yield, but was not soluble at all in various solvents and therefore could not be used as a carbon dioxide separation membrane. For the carbon dioxide separation membrane comprising a film coated with poly (ethylpropiolate) of Comparative Example 2, a relatively high permeability coefficient ratio and yield were obtained. However, when compared with the carbon dioxide separation membrane comprising the films of Examples 1 and 2 having ethyl groups, the permeation coefficient ratio is higher for the carbon dioxide separation membrane of Example 1, but the yield of the raw material is remarkably high. The carbon dioxide separation membrane of Example 2 is significantly inferior in both the permeation coefficient ratio and the raw material yield, and in addition, the dioxide dioxide of Examples 1 and 2 is inferior. Compared to any raw material of the carbon separation membrane, it was found that the raw material has a remarkably small degree of polymerization, and therefore has low toughness and cannot withstand repeated use over a long period of time. Thus, the carbon dioxide separation membrane comprising a film coated with poly (ethylpropiolate) of Comparative Example 2 was significantly inferior to the carbon dioxide separation membrane of the present invention when comprehensively evaluated. Regarding the carbon dioxide separation membrane composed of the film coated with poly (n-butylpropiolate) of Comparative Example 3, not only the permeation coefficient ratio and the yield of the raw material were remarkably inferior, but also the degree of polymerization of the raw material was It was found to be extremely small.

(O ₂ and N ₂ pure gas permeation tests)
As described above, the carbon dioxide separation membrane composed of the film coated with poly (ethoxyethylpropiolate) in Example 2 not only has a significantly high permeability coefficient ratio of CO _{2 to} CH ₄ , but is also the raw material poly Since the yield of (ethoxyethylpropiolate) was remarkably high and had a very good balance, each of the pure gases of O ₂ and N ₂ was further added to the carbon dioxide separation membrane. The transmission coefficient (P _O2 , P _N2 ) was measured. As a result, the transmission coefficients were 89 barrar and 31 barrer, respectively. Since the CO ₂ pure gas permeability coefficient (P _CO2 ) measured in Example 2 was 912 barrer, the ratio of the CO ₂ pure gas permeability coefficient to O ₂ and N ₂ was 10.2 (P _CO2 / P _{O2), respectively.} ) And 29.4 (P _CO2 / P _N2 ).

From the above results, the carbon dioxide separation membrane made of the film coated with poly (ethoxyethylpropiolate) obtained in Example 2 is selective to carbon dioxide with respect to each pure gas of O ₂ and N _2. It was found that the property of penetrating to is high. From these results, it was found that the film coated with poly (ethoxyethylpropiolate) obtained in Example 2 can selectively permeate and separate only carbon dioxide.

In the carbon dioxide separator composed of the homopolymer or copolymer represented by the formula (I) or the polymer blend of the present invention, R in the formula (I) contains at least one oxygen atom. From the above, the ability to selectively separate carbon dioxide mixed in helium, hydrogen, oxygen, nitrogen, carbon monoxide, various hydrocarbons, nitrogen oxides, sulfur oxides and mixtures thereof is remarkably excellent. In addition, since the homopolymers and copolymers represented by the formula (I) that are the raw materials can be produced in a relatively high yield, the carbon dioxide separation material obtained therefrom can also be produced at a low cost. Moreover, the lifetime is also long. Therefore, for example, it is expected to be used greatly in the future for separation and recovery of carbon dioxide from natural gas, methane fermentation gas, exhaust gas of thermal power generation, biomass pyrolysis gas, off-gas of oil fields, and the like.

Claims (9)

Formula (I)

(In formula (I), n represents an integer of 10 to 100,000, and R represents a monovalent hydrocarbon group containing at least one oxygen atom in the carbon-carbon bond.)
A carbon dioxide separator comprising a homopolymer or copolymer having a cis-type double bond in the main chain formed from propiolic acid or a derivative thereof, or a polymer blend thereof. The carbon dioxide separator according to claim 1, wherein R in the formula (I) represents a linear or cyclic monovalent aliphatic hydrocarbon group containing at least one oxygen atom in a carbon-carbon bond. . R in the above formula (I) is selected from the group consisting of an alkyl group having 2 to 10 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, and a combination thereof, wherein the above group is The carbon dioxide separator according to claim 1, wherein the carbon-carbon bond contains at least one oxygen atom. R in the above formula (I) is represented by the formula —CHR ¹ —CHR ¹ —O—R ² , wherein each R ¹ independently represents a hydrogen atom and an alkyl group having 1 to 2 carbon atoms. The carbon dioxide separator according to claim 1, wherein the carbon dioxide separator is selected from the group consisting of R ^{2 and} an alkyl group having 1 to 5 carbon atoms. The carbon dioxide separation according to claim 1, wherein R in the formula (I) is selected from the group consisting of a methoxyethyl group, an ethoxyethyl group, a 1-methoxy-2-propyl group and a 1-ethoxy-2-propyl group. Wood. The carbon dioxide separator according to any one of claims 1 to 5, wherein n represents an integer of 100 to 5,000. It is for carbon dioxide separation in helium, hydrogen, oxygen, nitrogen, carbon monoxide, hydrocarbon having 1 to 5 carbon atoms, nitrogen oxide, sulfur oxide, or a mixture thereof. Carbon dioxide separator as described in 1. A homopolymer or copolymer having a cis-type double bond in the main chain formed from propiolic acid or a derivative thereof represented by the above formula (I) is polymerized using a group 8-10 metal compound as a catalyst, Item 8. The carbon dioxide separator according to any one of Items 1 to 7. The separation membrane which consists of a carbon dioxide separation material as described in any one of Claims 1-8.