JP4932141B2 - Method for controlling properties of polymer complexes - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a procedure for modifying a polymer complex, and new various polymer complexes produced by the procedure. <P>SOLUTION: This method for controlling the characteristic of the polymer complex is to modify the characteristic of the polymer complex by a chemical modifier such as an alcohol having &le;500 molecular weight, a ketone, a nitrile, an ether, an amide or inorganic salts. By the method, it is possible to convert the polymer complex to the polymer complexes having various characteristics, such as an adsorption characteristic, etc., by chemical modifications. <P>COPYRIGHT: (C)2006,JPO&amp;NCIPI

Description

  The present invention relates to a method for controlling characteristics of a polymer complex by chemical modification.

  A polymer complex composed of an organic ligand having two or more coordination sites and a metal ion can use various metal ions, counter ions and ligands as raw materials. Furthermore, even if the same raw material is used, the three-dimensional structure may be different. Therefore, it is possible to make very many kinds of substances. Such polymer complexes having various structures are expected to exhibit various properties (Non-Patent Document 1).

  For example, the function of a polymer complex having a large number of pores inside and adsorbing various substances therein has recently been clarified. In general, adsorbents such as activated carbon and zeolite are widely used for gas storage using their adsorption performance, gas separation using the difference in adsorption capacity depending on the type of gas, or water purification by liquid phase adsorption, etc. In recent years, with the growing awareness of the environment, adsorption storage of gases that are clean energy sources such as methane and hydrogen has been studied, and this polymer complex is also expected to be applied to similar industrial uses (non- (See Patent Document 2 and Non-Patent Document 3).

  Compared to conventional zeolite, activated carbon, and the like, polymer complexes are generally considered to be soft (flexible) materials because they contain weak intermolecular interactions such as coordination bonds and hydrogen bonds. There are known examples in which the structure changes due to an external stimulus such as gas pressure and the gas adsorption characteristics change (see Non-Patent Documents 4 and 5).

  Utilizing the so-called gate phenomenon (see Non-Patent Document 6) in which such gas adsorption characteristics change is considered to be used as a novel gas storage material.

In addition to the adsorption of substances, polymer complexes are expected to be used for conductivity, catalysts, optical materials and the like because of their various structures. However, there are few practical examples of research on polymer complexes, and few methods are known for controlling the functions of polymer complexes.
Susumu Kitagawa, Integrated Metal Complex, Kodansha Scientific, 2001, 214-226 Susumu Kitagawa, Integrated Metal Complex, Kodansha Scientific, 2001, pp. 192-223 Naoshi Okawa, Tsubasa Ito, Science of Integrated Metal Complexes, Chemistry Dojin, 2003, pages 135-143 Kitagawa, S .; et al. , Angelwandte Chem. Int. Ed. (2003) 428 Seki, K .; et al. Phys. Chem. Chem. Phys. , (2002) 4, 1968-1971 Onishi, S .; et al. , Applied Surface Sci. 196 (2002) 81-88.

  An object of this invention is to provide the method of changing the characteristic of a polymer complex.

  As a result of intensive studies to solve the above-described problems, the present inventors have made a polymer complex by allowing a certain chemical substance (hereinafter referred to as a chemical modifier) to act on the polymer complex. The present invention was completed by finding that the characteristics of the material changed in various ways.

  That is, the present invention is a method for changing the properties of a polymer complex by chemical modification.

The present invention
The polymer complex represented by the following formula (i) that does not exhibit gas gate adsorption / desorption ability is directly impregnated or vaporized into a chemical modifier selected from the group consisting of acetone and ethanol. It is a property control method for a polymer complex characterized in that the polymer complex is modified to a polymer complex that exhibits gas gate adsorption / desorption ability by acting for 5 minutes or more.
(Wherein, X represents a divalent copper ion, Y represents an anion composed of BF ₄ ^— , L represents an organic ligand composed of 4,4′-bipyridyl, a is 2, and m is 0 or 0.5 or more and 8 or less.)

  According to the method of the present invention, the polymer complex can be converted into a polymer complex having various characteristics by chemically modifying the polymer complex. That is, the present invention provides a method for chemically modifying a polymer complex and a novel polymer complex having various properties produced by the method.

  The polymer complex used for the modification in the present invention means a metal complex having a higher order structure composed of a metal ion and an organic ligand having two or more coordination points in one molecule. For example, there are many reported examples of polymer complexes composed of an organic ligand having a coordination point at both ends of a molecule and metal salts such as 4,4′-bipyridyl (Zawortko, J. et al., Chem. Rev. (2001) 101, 1629-1658). In the polymer complex, there are a case where an inorganic anion is contained as a counterion of a metal ion, and a case where a ligand itself has a charge and does not contain an inorganic anion because it functions as a counterion (Kitagawa, S. et al., Angew. Chem. Int. Ed. (2003) 42, 4, 428-431), any of the polymer complexes used in the present invention may be used.

  Examples of the polymer complex containing inorganic anions include compounds represented by the following formula (i).

(Wherein, X is a divalent transition metal ion, Y is an anion, L is an organic ligand having two coordination sites, a is L is not charged, and Y is monovalent. 2 if L is an anion, 1 if L is not charged and Y is a divalent anion, 0 if L is charged monovalent, m is 0 or 0 .5 or more and 8 or less)
The raw material of the compound represented by Formula (i) is illustrated.

One of the raw material is a metal salt, a compound represented by XY _a.

  Here, as X, a divalent transition metal ion, for example, an ion of iron, cobalt, nickel, copper, zinc or the like can be mentioned. In terms of ease of making a complex, ions of cobalt, nickel, copper, and zinc are preferable, and ions of nickel and copper are more preferable.

Y is a monovalent or divalent anion. Examples of the monovalent anion include Cl ⁻ , Br ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , CF ₃ SO ₃ ⁻ , CF ₃ CO ₂ ^−. For example, acid ions of strong acids such as BF ₄ ⁻ , PF ₆ ⁻ , CF ₃ SO ₃ ⁻ , CF ₃ CO ₂ ⁻ , and more preferably BF ₄ ⁻ , PF ₆ ⁻ , and CF ₃ SO ₃ ⁻ are mentioned in terms of ease of making the complex. Examples of the divalent anion include SiF ₆ ²⁻ , GeF ₆ ²⁻ , SbF ₆ ²⁻ , SO ₄ ^{2− and the} like. SiF ₆ ²⁻ and SO ₄ ²⁻ are preferable in terms of ease of forming the complex.

Furthermore, another kind of raw material is the organic ligand L. Here, L is a ligand having two coordination sites at relatively distant positions in the molecule. That is, it is an ABA (A = 4-pyridyl group) type ligand having 4,4′-bipyridyl and one 4-pyridyl group at both ends of the molecule. Here, as B, —CH ₂ —, —CH═CH— (cis or trans), —CO—NH—, 1,4-phenylene or substituted phenylene, 1,3-phenylene or substituted phenylene, 2,5 -Thiophenyl or a substituted product thereof, 2,7-fluorenyl or a substituted product thereof, 1,4-diethynylbenzene and the like. 4,4′-bipyridyl, 1,4-bis (4-pyridyl) benzene, 1,4-bis (4-pyridyl) thiophene and 1,4-bis (4-pyridyl) are relatively inexpensive ) Acetylene is preferable, and 4,4′-bipyridyl is preferable because it is easily available as a general-purpose product.

  In addition, since the polymer complex of the present invention is a substance having polarity, it may include water, alcohol, ether or the like. M representing the number of water molecules to be included varies from 0.5 to 8, and reversibly changes depending on the environment in which the complex is stored. In addition, these are only weakly bonded to the polymer complex, and may be removed by a treatment such as drying under reduced pressure, and m may be 0. In such a case, water represented by the formula (ii) may be used. It may change to a complex that does not contain.

(Wherein, X is a divalent transition metal ion, Y is an anion, L is an organic ligand having two coordination sites, a is L is not charged, and Y is monovalent. (In the case of an anion, it is 2, and when L is not charged and Y is a divalent anion, it is 1, and when L is charged monovalent, it is 0.)
However, these complexes return to the original complex represented by the formula (i) by absorbing moisture. Therefore, even a complex represented by the formula (ii) can be regarded as essentially the same as the polymer complex used in the present invention.

  Moreover, as a polymer complex which does not contain the inorganic anion used for modification | denaturation by this invention, the compound represented by a following formula (iii) can be illustrated, for example.

(Wherein, X represents a divalent transition metal ion, C represents an aromatic carboxylic acid ligand, and L ′ represents a non-carboxylic acid type ligand having two coordination sites.)
Examples of the raw material for the compound represented by formula (iii) are given below.

  One of the raw materials is a metal salt containing a transition metal ion X. Here, X is a divalent transition metal ion, for example, an ion of iron, cobalt, nickel, copper, zinc or the like. In terms of ease of making a complex, ions of cobalt, nickel, copper, and zinc are preferable, and ions of nickel and copper are more preferable.

Examples of the counter ion of X include monovalent or divalent anions. For example, Cl ⁻ , Br ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , CF ₃ SO ₃ ⁻ , CF ₃ CO ₂ ⁻ , CH ₃ Examples thereof include ions such as CO ₂ ⁻ , NO ₃ ⁻ , SiF ₆ ²⁻ , GeF ₆ ²⁻ , SO ₄ ²⁻ . BF ₄ ⁻ , PF ₆ ⁻ , CF ₃ SO ₃ ⁻ , CF ₃ CO ₂ ⁻ , CH ₃ CO ₂ ⁻ , NO ₃ ⁻ , SiF ₆ ²⁻ , GeF ₆ ²⁻ , SO ₄ ^2- , more preferably BF ₄ ⁻ , PF ₆ ⁻ , CF ₃ SO ₃ ⁻ , CF ₃ CO ₂ ⁻ , CH ₃ CO ₂ ⁻ , and NO ₃ ⁻ .

  These counter ions may be used alone or in combination.

For example, when a copper salt is used as the metal salt, Cu (BF ₄ ) ₂ may be used alone, or Cu (BF ₄ ) ₂ and Cu (OAc) ₂ may be mixed and used. The mixing ratio may be arbitrary.

  C is an aromatic carboxylic acid ligand. An aromatic carboxylic acid-based ligand refers to a compound in which one or more carboxyl groups are substituted on an aromatic group.

  Examples of ligands substituted with one carboxyl group include 2-hydroxybenzoic acid containing no functional groups other than carboxyl groups or functional groups other than carboxyl groups such as benzoic acid and 4-carboxybiphenyl. 3-hydroxybenzoic acid, 4-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 2-aminobenzoic acid, 3-aminobenzoic acid, 4 -Aminobenzoic acid, 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 2-methoxybenzoic acid, 3-methoxybenzoic acid, 4-methoxybenzoic acid, 2,4 -Dimethoxybenzoic acid, 2,5-dimethoxybenzoic acid, 3,5-dimethoxybenzoic acid, 4-acetoxybenzoic acid, 2,4-diacetoxybenzoic acid Acid, 2,5-diacetoxy benzoic acid, 4-acetyl benzoic acid, 2,4-diacetyl-benzoic acid can be exemplified widely 2,5 diacetyl benzoate.

  Examples of ligands containing two or more carboxyl groups include terephthalic acid, 1,3,5-benzenetricarboxylic acid, pyromellitic acid, 4,4′-biphenyldicarboxylic acid, 2,5-dimethylterephthalic acid. Etc. can be illustrated. In these carboxylic acid-based ligands, one of the carboxyl groups is ionized during coordination and coordinated as a carboxylic acid anion. From the viewpoint that the compound can be obtained relatively inexpensively and the stability of the compound is high, a benzoic acid substituted with a hydroxy group or a methoxy group, an unsubstituted benzoic acid, terephthalic acid, or 4,4'-biphenyldicarboxylic acid is preferable.

Furthermore, another kind of raw material is a non-carboxylic acid type ligand L ′. Here, L ′ is a ligand having two coordination sites that are not carboxyl groups at a relatively distant position in the molecule, that is, 4,4′-bipyridyl or 4-pyridyl at both ends of the molecule. It is a ligand having one group at a time, that is, a ligand of ABA (A = 4-pyridyl group) type. Here, B is —CH ₂ —, —CH═CH— (cis or trans), —CO—NH—, 1,4-phenylene or substituted phenylene, 1,3-phenylene or substituted phenylene, 2,5- Examples include thiophenyl or a substituted product thereof, 2,7-fluorenyl or a substituted product thereof, and 1,4-diethynylbenzene. 4,4′-bipyridyl, 1,4-bis (4-pyridyl) benzene, 1,4-bis (4-pyridyl) thiophene, 1,4-bis (4-pyridyl) are relatively inexpensive. ) Acetylene is preferred, and 4,4′-bipyridyl is preferred because it is readily available as a general-purpose product.

As an example of the three-dimensional structure of the [XA ₂ L ′ ₂ ] _n- type polymer complex, an embodiment in which linear main chains are assembled (FIG. 1) or a lattice structure (FIG. 2) can be considered, but either may be used.

  In addition, since the polymer complex of the present invention is a substance having polarity, when it comes into contact with organic molecules such as water, alcohol or ether, it contains water or an organic solvent, or in some cases, metal ions and ligands. In some cases, water or an organic solvent is inserted therebetween, and for example, the complex may be changed to a complex complex represented by the formula (iv).

(Wherein, X is a divalent transition metal ion, D is a benzoic acid type ligand, L ′ is a non-carboxylic acid type ligand having two coordination sites. Z is water, alcohol, A low molecule such as ether is shown, and m is 0.5 or more and 8 or less.)
However, organic molecules such as water, alcohol and ether in these complex complexes are only weakly bonded to the polymer complex, and are removed by a treatment such as drying under reduced pressure, and represented by the original formula (iii). Return to the complex. Therefore, even a complex represented by the formula (iv) can be regarded as essentially the same as the polymer complex used in the present invention.

  In the method of the present invention, it is possible to produce a novel polymer complex having various characteristics by chemically modifying the polymer complex with various chemical modifiers. As the chemical modifier to be acted, a compound having a so-called hetero atom such as oxygen, nitrogen, sulfur or the like in the molecule is preferable in order to electronically interact with the polymer complex. Such compounds include organic molecules and inorganic salts.

  Examples of organic molecules include linear or branched aliphatic alcohols such as methanol, ethanol, 2-methoxyethanol, 2-propanol and ethylene glycol, and aromatic alcohols having an aromatic ring such as benzyl alcohol in the molecule. Alcohols such as diethyl ether and tetrahydrofuran, nitriles such as acetonitrile and benzonitrile, esters such as ethyl acetate, ketones such as acetone, halogen compounds such as dichloromethane, benzene, toluene A wide range of aromatic compounds such as dimethylacetamide, sulfoxides such as dimethylsulfoxy degree, sulfones such as dimethylsulfone, and the like. Among these, alcohols, ketones, nitriles, ethers, esters, and amides are preferable because of strong interaction with the polymer complex. Furthermore, in terms of low molecular weight and high permeability to polymer complexes, methanol, ethanol, 1-propanol, ethylene glycol, acetonitrile, methyl acetate, ethyl acetate, diethyl ether, tetrahydrofuran, acetone, benzene, toluene, Xylene, dimethylformamide, dimethylacetamide, dimethylsulfoxide are particularly preferred. In addition, in these compounds, for example, 2,2,2-trifluoroethanol, 2-chloroethanol, 1,1,1-trifluoroacetone and the like containing halogen elements such as fluorine and chlorine are also included in the polymer complex. This is preferable in that the interaction of the chemical modifier becomes strong. When a strongly acidic compound such as sulfonic acid or a basic compound such as aniline is used, the polymer complex may be decomposed. In addition, chemical substances that do not contain heteroatoms such as hexane may have a weak interaction with the polymer complex. These may be used alone or in combination of two or more.

  Examples of inorganic salts include copper (II) fluoride, copper (II) chloride, copper (II) bromide, copper (II) acetate, copper (II) sulfate, copper (II) trifluoromethanesulfonate, trifluoro Transition metal salts such as copper (II) acetate, nickel chloride (II), nickel bromide (II), silver chloride (I), silver bromide (I), ammonium chloride, ammonium bromide, hexafluorosilicic acid A wide range of ammonium salts such as ammonium and ammonium hexafluorophosphate can be exemplified. Transition metal acetates, trifluoromethanesulfonates, trifluoroacetates and ammonium salts are preferred because of their high solubility and strong interaction with the polymer complex. These may be used alone or in combination of two or more.

  In the case of organic molecules, the molecular weight of the chemical modifier is 500 or less, preferably 300 or less, from the viewpoint of permeability to the polymer complex.

  The modification with the chemical modifier is performed by causing the chemical modifier to act on the polymer complex. For example, if the chemical modifier is liquid at room temperature, such as ethanol or acetone, the chemical modifier can be directly impregnated with the polymer complex, or the chemical modifier vapor can be exposed to the polymer complex. Denaturation can be performed. Moreover, when a chemical modifier is solid at normal temperature, chemical modification can be carried out by dissolving a chemical modifier in a solvent and immersing a polymer complex there.

  The amount of the chemical modifier used is preferably 0.2 mol times to 10000 mol times, more preferably 1 mol times to 5000 mol times, based on the metal atom contained in the polymer complex. If the amount is small, the denaturation may be insufficient. When the chemical denaturant is liquid, a method of recovering the chemical denaturant by distillation under reduced pressure after use in a large excess is also recommended. In this case, since the chemical modifier can be recovered later, there is no problem even if the chemical modifier is used in a large excess amount exceeding 5000 mol times.

  The action time of the chemical modifier is preferably 5 minutes to 20 days, more preferably 4 hours to 3 days. If the action time is too short, modification may be insufficient. If the action time is too long, modification may be excessive and the polymer complex may be decomposed.

  The temperature at which the chemical modifier is allowed to act is preferably -20 ° C to 100 ° C, more preferably 0 ° C to 80 ° C. If the temperature is too low, modification may be insufficient, and if the modification temperature is too high, modification may be excessive and the polymer complex may be decomposed.

  The reaction can be carried out using an ordinary glass-lined SUS reaction vessel and a mechanical stirrer. After the modification, when the liquid is impregnated with the polymer complex, the modified polymer complex is taken out by filtering the solid polymer complex or removing the chemical modifier under reduced pressure. It is possible. In addition, when the chemical modifier is solid and dissolved in a solvent to act on the polymer complex, it is denatured by filtering the solid polymer complex and then washing with a solvent that can dissolve the chemical modifier. It is possible to remove the polymer complex.

  By the method of the present invention, it is possible to impart new characteristics to the polymer complex.

  As one of the actions of the chemical denaturing agent, for example, an adsorption characteristic that did not exist before the chemical denaturation is expressed by the denaturation. Further, as another action, there is a change in the characteristics of the gas gate adsorption / desorption ability. Gas adsorption / desorption ability of gas means that, when a polymer complex is used as a gas adsorbent, gas is not adsorbed up to a certain pressure, but gas adsorption starts when a certain pressure is exceeded. It refers to the characteristic that gas is not released up to a certain pressure, but gas is suddenly released when the pressure falls below a certain pressure (Kitagawa, S. et al, Agewandte Chem. Int. Ed. (2003) 428). By making use of this gate adsorption / desorption capability, there is an increasing expectation for the use of a material having gas gate adsorption / desorption capability (hereinafter referred to as gate material) as a gas storage material.

  As an application example of the gate material, when it is used as a gas adsorbent for the pressure swing adsorption method (hereinafter referred to as “PSA method”) for the purpose of gas separation, the required power can be reduced as the pressure difference between adsorption and desorption decreases. Energetically favorable. Therefore, a gate material having a small pressure difference between adsorption and desorption can be suitably used as a PSA application. Moreover, in an adsorbent for a gas tank attached to an automobile engine, for example, it is preferable that the gas discharge pressure can hold the gas at a pressure higher than the pressure at which the engine operates. This is because when the pressure is unnecessarily high, the strength of the tank is required. On the other hand, when the gas holding pressure is too low, the operation of the engine is hindered, so it is important that the gas can be held at a certain pressure. In this respect, since the gate material releases the gas at a certain constant pressure, it can be suitably used when the constant pressure matches the pressure required for the apparatus.

  In the method of the present invention, the gate adsorption / desorption ability can be changed by chemically modifying the gate material. The gas adsorption / desorption pressure is determined according to the method and apparatus to be applied, and it cannot be said which pressure is generally preferred. However, the difference in gate adsorption pressure and gate desorption pressure due to denaturation is small for PSA applications. Is preferable.

In the reaction system of the present invention, the mechanism of denaturation with a chemical denaturant is assumed to be as follows. For example, [Cu (BF ₄ ) ₂ (bpy) ₂ (H ₂ O) ₂ ] _n which is a gate material has a structure in which lattice-like layers are stacked, and this stacked structure is an external stimulus such as gas pressure. It is thought that it causes a structural change. In conventional gas stimulation, it is considered that the conversion between the two phases, in which there is no pore and in which the lattice is completely shifted and the pores are opened to the maximum, occurs (FIG. 3). On the other hand, since the chemical modifier has a stronger interaction than the gas with respect to the polymer complex, a phase other than the above-described two phases, for example, the lattice is shifted halfway and the pores are half exposed, It can be inferred that a new phase having a three-dimensional structure different from the conventional one is generated, and that this expresses a new function (FIGS. 4 and 5). That is, in this case, the chemical modifier does not necessarily remain inside the polymer complex, and has a function of generating a complex having a new structure as a modifying action. Another mechanism is that a small amount of the chemical modifier remains in the lattice of the polymer complex after the chemical modification treatment, and this acts as a catalyst that facilitates the displacement of the lattice when gas enters. It can be inferred that this is happening (FIG. 6). In any case, the chemical modifier is preferably a chemical substance containing a heteroatom that interacts with the polymer complex, but these are only speculations and do not limit the present invention.

Since the polymer complex is selected according to the use, it cannot be uniquely determined, but here, [Cu (BF ₄ ) ₂ (bpy) ₂ (H ₂ O) ₂ ] _n (where bpy Represents 4,4′-bipyridyl). Polymer complex [Cu (BF ₄ ) ₂ (bpy) ₂ (H ₂ O) ₂ ] _n is obtained by mixing an aqueous solution of copper (II) borofluoride and a methanol solution of bpy while heating to 60 ° C. It is obtained by drying the dried powder under reduced pressure.

(Examples 1 and 2)
Glass measurement for bell soap 36 (manufactured by Nippon Bell Co., Ltd.) capable of sealing 50 mg of polymer complex [Cu (BF ₄ ) ₂ (bpy) ₂ (H ₂ O) ₂ ] _n with a Teflon (registered trademark) cock as an adsorbent. After putting in a tube and adding 2 mL of the chemical denaturant shown in Table 1 and sealing it, the adsorbent was allowed to act at room temperature for a predetermined time (specific conditions are described in Table 1). Thereafter, the pressure was reduced at room temperature for 10 minutes using a rotary pump, the chemical denaturant was removed, and the resultant was further dried under reduced pressure at 3 Pa for 10 hours. Thereafter, the adsorption property of nitrogen at 77K of the chemically modified adsorbent was evaluated (the adsorption isotherm is shown in FIGS. 7 and 8. The horizontal axis represents the relative pressure of nitrogen at 77K, and the vertical axis represents the adsorption. The amount of nitrogen gas adsorbed per gram of the material in the standard state is shown). As a result, gas adsorption of 300 ml / g (STP) or more was shown in both ethanol treatment and acetone treatment. On the other hand, in the adsorbent not chemically modified, when the same measurement was performed, the adsorption amount of nitrogen was 30 ml / g (STP) or less (FIG. 9).

  In addition, the adsorption characteristics of methane gas at 303 K were evaluated (FIG. 10, with ethanol treatment). For comparison, an adsorption / desorption isotherm of methane gas at 303 K after activation of the unmodified complex by heating under reduced pressure at 125 ° C. and 3 Pa or less is shown (FIG. 10, untreated). On the other hand, when the same measurement was performed on an adsorbent that was not chemically modified or heated and reduced in pressure, the adsorbed amount of methane was 1% by mass or less.

  This adsorbent before chemical modification does not exhibit gas adsorption characteristics unless it is pretreated at 100 ° C. or higher under reduced pressure. However, in the case of a polymer complex modified with a chemical modifier, nitrogen is simply dried at room temperature. Gas adsorption characteristics were developed (see FIGS. 7, 8 and 10). That is, by chemical modification with a chemical modifier, it could be converted into a polymer complex having a gas adsorption ability without being subjected to heat and pressure reduction treatment. Furthermore, in the polymer complex after chemical modification, the amount of gas occlusion remains almost the same as that before chemical modification, the adsorption rising pressure (gate pressure) decreases, and the polymer can store gas at a lower pressure. It could be converted into a complex (see FIGS. 7, 8, and 10). In addition, in the adsorption / desorption of methane gas, the pressure difference between adsorption and desorption was reduced by chemical modification compared with that before modification (FIG. 10, the horizontal axis represents the methane gas pressure, and the vertical axis represents the methane adsorption amount. Show).

(Example 3)
As an adsorbent, 50 mg of a polymer complex [Cu (BF ₄ ) ₂ (bpy) ₂ (H ₂ O) ₂ ] _n was placed in a glass container and placed in a glass container that can be sealed once. 3 mL of methanol was placed between the outer and inner containers, sealed, and the polymer complex was exposed to methanol vapor for 12 days. Thereafter, the polymer complex was opened in a nitrogen stream so as not to absorb moisture, and the modified polymer complex was put into a glass tube for Bell Soap 36 (manufactured by Nippon Bell Co., Ltd.). The nitrogen adsorption characteristics were evaluated in the same manner as in Examples 1 and 2. The results are shown in FIG. When chemically modified with methanol gas, the nitrogen adsorption and desorption characteristics were the same as when the polymer complex as the raw material was activated at 125 ° C. That is, it has been found that gas adsorption characteristics are exhibited without chemical activation by methanol modification.

  According to the present invention, the function of the polymer complex can be changed or a new function can be imparted. Using this, for example, there is a possibility that new properties such as gas adsorption properties, conductivity, and optical properties can be imparted to a polymer complex that originally has no properties. Alternatively, there is a possibility that an amount of adsorption, an adsorption / desorption pressure, an adsorbed gas type, and the like can be changed in a gas adsorption characteristic that originally changes a characteristic.

[XA ₂ L ′ ₂ ] is an example of a three-dimensional structure of an _n- type polymer complex. [XA ₂ L ′ ₂ ] is another example of a three-dimensional structure of an _n- type polymer complex. It is an aspect of opening and closing the pores of the polymer complex. It is a novel structure of a polymer complex produced by chemical modification. It is another novel structure of a polymer complex produced by chemical modification. It is another novel structure of a polymer complex produced by chemical modification. 2 is a nitrogen adsorption / desorption isotherm of the chemically modified complex of Example 1. FIG. Example 2 is a nitrogen adsorption / desorption isotherm of a chemically modified complex. It is a nitrogen adsorption / desorption isotherm of a complex which has not been chemically modified. 2 is a methane adsorption / desorption isotherm of the chemically modified complex of Example 2. FIG. 3 is a nitrogen adsorption / desorption isotherm of the chemically modified complex of Example 3. FIG.

Claims (4)

The polymer complex represented by the following formula (i) that does not exhibit gas gate adsorption / desorption ability is directly impregnated or vaporized into a chemical modifier selected from the group consisting of acetone and ethanol. A method for controlling the properties of a polymer complex , wherein the polymer complex is allowed to act for 5 minutes or longer to modify the polymer complex into a polymer complex that exhibits gas gate adsorption / desorption ability .
(Wherein, X represents a divalent copper ion, Y represents an anion composed of BF ₄ ^— , L represents an organic ligand composed of 4,4′-bipyridyl, a is 2, and m is 0 or 0.5 or more and 8 or less .) It said gas is nitrogen or methane, characteristic control method of the polymer complex of claim 1, wherein. The method for controlling characteristics of a polymer complex according to claim 1 or 2 , wherein the chemical modifier is allowed to act for 5 minutes to 20 days. The method for controlling characteristics of a polymer complex according to any one of claims 1 to 3 , wherein the chemical modifier is allowed to act at a temperature of -20 ° C to 100 ° C.