JP2009163918A - Composite of copolymer and carbon material and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite introducing a skeleton having heat resistance higher than that of polyphenyl quinoxaline into a molecule of a compound, and containing a quinoxaline skeleton-containing compound for a negative electrode active material of a proton battery having high electrochemical performance, and to provide the manufacturing method of an electrode material having characteristics suitable for a proton transfer battery. <P>SOLUTION: The composite is composed of a copolymer containing a quinoxaline structural unit represented by general formula (1) ( in the formula, R<SB>1</SB>and R<SB>4</SB>independently represent a hydrogen atom, an alkyl group, an aryl group, or an alkoxy group) and a benzimidazole structural unit represented by general formula (3) (in the formula, R<SB>1</SB>represents a hydrogen atom, an alkyl group, an aryl group, or an alkoxy group), and a conductive carbon material. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a composite for use as an electrode material for a proton transfer battery and a method for producing the same.
That is, in the present invention, a composite of a conductive carbon material and a copolymer containing a quinimidazoline skeleton having a large proton insertion / release capacity and also a benzimidazole skeleton having excellent heat resistance is intended for use as an electrode active material. The present invention relates to a product and a manufacturing method thereof.

In recent years, new secondary batteries such as nickel / hydrogen batteries and Li-ion secondary batteries have been rapidly mounted on small portable devices due to their high energy density, and have shown rapid growth. In particular, when a Li-ion battery is used, the light weight, small size, and thickness of the device are further advanced, and the secondary battery has become the mainstream. For example, LiCoO ₂ , LiNiO ₂ , LiMn ₂ O ₄ , MoS _{2 and} other metal oxides, metal sulfides are used as positive electrodes, lithium, lithium alloys, carbon materials and inorganic compounds that can occlude and release lithium ions are used as negative electrodes, Many researches have been made on lithium ion batteries using organic electrolytes. However, since these lithium-based batteries use lithium and / or lithium-based compounds that are active and easily oxidized in moisture and air, there are concerns about safety and reliability at the time of short circuit, high temperature, liquid leakage, opening, etc. Safety measures have been taken in various ways, such as ingenuity, PTC element incorporation, and sealing.

On the other hand, a proton battery intended to improve safety, high-speed current characteristics and the like, which are disadvantages of the new battery such as the Li-ion battery, has been proposed (Patent Document 1). The proton battery has features such as excellent safety, reliability, current characteristics, and long life. As electrode active materials for these batteries, polypyridine, polypyrimidine, sulfonic acid side chain, hydroquinone polymers or manganese oxides, or combinations thereof have been proposed. Since these can easily insert / release protons, secondary batteries with excellent safety and high-speed current characteristics can be obtained. However, since the proton insertion / release capacity is insufficient, the energy density of the battery is low. It was greatly inferior to the conventional new battery (Patent Document 2). Polyphenylquinoxaline (PPQ) for negative electrode
In addition, by combining powdered carbon and polyphenylquinoxaline, sufficient energy density, electromotive force, and cycleability were achieved, which could be put to practical use (Patent Document 3).
However, a proton battery using polyfephenylquinoxaline as an electrode active material has a problem that it deteriorates due to heat.
Patent No. 3039484 Japanese Patent No. 2974012 Japanese Patent No. 3144410

The present invention is a composite comprising a quinoxaline skeleton-containing compound for a proton battery negative electrode active material, in which a skeleton having higher heat resistance than that of polyphenylquinoxaline, which has been studied in the past, is introduced into the molecule of the compound and is excellent in electrochemical performance. Is to provide.

As a result of intensive studies in view of the above problems, the present inventors have found a method of incorporating polybenzimidazole, which is known as a heat-resistant polymer, into polyphenylquinoxaline, which has been conventionally studied as an electrode active material, and obtained by this method. It has been found that an electrode active material using a composite of a copolymer and a conductive carbon material is excellent in terms of electrochemical properties such as conductivity and capacity.

That is, the present invention relates to the following composites [1] to [23] and a method for producing the same.
[1] General formula (2)

(Wherein R ₁ and R ₄ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group) and a quinoxaline structural unit represented by the general formula (3)

(Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group), a copolymer containing a benzimidazole structural unit represented by:
Conductive carbon materials;
And composites.
[2] The copolymer according to [1] is represented by the following general formula (6)

(Wherein R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group, and m and n each independently represents an integer of 6 to 150). A composite comprising a phenylquinoxaline structural unit and a phenylbenzimidazole structural unit represented by:
[3] Tetracarbonyl compound having two 1,2-diketone structures in the molecule, dialdehyde compound and general formula (1)

(Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group, or an alkoxy group). A dehydration copolycondensation polymerization is performed in the presence of an oxidizing agent and a conductive carbon material. ,
General formula (2)

(Wherein R ₁ and R ₄ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group) and a quinoxaline structural unit represented by the general formula (3)

(Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group). A method for producing a composite of a copolymer containing a benzimidazole structural unit represented by
[4] The tetracarbonyl compound is represented by the following general formula (4):

(Wherein R ₂ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group),
The dialdehyde compound is represented by the following general formula (5)

(Wherein R ₃ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group), and
The copolymer is represented by the following general formula (6)

(In the formula, R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group, and m and n each independently represents an integer of 6 or more and 150 or less.
The production method according to [3], which is a copolymer represented by
[5] The tetracarbonyl compound is reacted in advance with an excess of the tetraamine compound relative to the tetracarbonyl compound to form a mixture of an oligomer having a quinoxaline skeleton and a tetraamine compound, and then the dialdehyde compound is [3] or [3], wherein dehydration copolycondensation is performed by reacting in the presence of a conductive carbon material and an oxidizing agent.
4].
[6] A mixture of an oligomer having a phenylbenzimidazole skeleton and a tetraamine compound is formed by previously reacting the dialdehyde compound with an excess of the tetraamine compound in the presence of an oxidizing agent. Then, the tetracarbonyl compound is reacted in the presence of a conductive carbon material to perform dehydration copolycondensation, [3] or [4].
[7] A conductive carbon material coated with an oligomer having a quinoxaline skeleton by reacting the tetracarbonyl compound and an excess amount of the tetraamine compound with respect to the tetracarbonyl compound in the presence of a conductive carbon material in advance. The method according to [3] or [4], wherein after forming a mixture with a tetraamine compound, the dialdehyde compound is reacted in the presence of an oxidizing agent to perform dehydration copolycondensation.
[8] The dialdehyde compound and an excess of the tetraamine compound relative to the dialdehyde compound are reacted in advance in the presence of a conductive carbon material and an oxidizing agent to coat the oligomer having a phenylbenzimidazole skeleton. The method according to [3] or [4], wherein after forming a mixture of a conductive carbon material and a tetraamine compound, the tetracarbonyl compound is reacted to perform dehydration copolycondensation.
[9] The production method according to any one of [3] to [8], wherein the polymerization is performed in the presence of a solvent.
[10] The method according to [9], wherein the concentration of the total monomer composed of the tetracarbonyl compound, the dialdehyde compound and the tetraamine compound in the solvent at the start of polymerization is 5% by mass or more and 40% by mass or less. Manufacturing method.
[11] The solvent is N, N-dimethylformamide [9] or [1
0].
[12] The polymerization temperature is from 100 ° C. to 150 ° C. [9] to [11]
The manufacturing method in any one of.
[13] The tetracarbonyl compound is an aromatic tetracarbonyl compound [3] to [3]
[12] The production method according to any one of [12].
[14] The production method according to any one of [3] to [12], wherein the tetracarbonyl compound is bis- (phenylglyoxyloyl) benzene.
[15] The dialdehyde compound is an aromatic dialdehyde compound [3] to [14]
The manufacturing method in any one of.
[16] The production method according to [3] to [14], wherein the dialdehyde compound is either terephthalaldehyde or isophthalaldehyde.
[17] The production method according to any one of [3] to [16], wherein the tetraamine compound is an aromatic amine compound.
[18] The tetraamine compound is 3,3′-diaminobenzidine [3] to [1
6] The method for producing a copolymer according to any one of the above.
[19] The production method according to any one of [3] to [18], wherein the oxidizing agent is air.
[20] The production method according to any one of [3] to [19], wherein the conductive carbon material is ketjen black.
[21] The production method according to any one of [3] to [20], further comprising a step of, after the reaction, separating the reaction mixture by filtration and washing with an alcohol solvent.
[22] A composite obtained by the production method according to any one of [3] to [21].
[23] A proton transfer battery using the composite according to any one of [1], [2] and [22] as an electrode.

The composite of the copolymer having a quinoxaline skeleton and a benzimidazole skeleton according to the present invention and a conductive carbon material has a high heat-resistant skeleton, and in terms of electrochemical properties, the composite having only a conventional quinoxaline skeleton. It shows the same performance as a compound in which molecules are combined with a conductive carbon material.

The specific contents of the present invention will be described in detail below.
A composite of a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit and a conductive carbon material, a production method thereof, and raw materials thereof will be described.

<Composite of copolymer and conductive carbon material>
The copolymer compounded with the conductive carbon material in the composite of the present invention has the general formula (2)

(In the formula, R ₁ and R ₄ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group.)
A quinoxaline structural unit represented by the general formula (3)

(In the formula, R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group.)
A tetracarbonyl compound, a dialdehyde compound, and a general formula (1) having a benzimidazole structural unit represented by

(In the formula, R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group.)
Is synthesized by dehydration copolycondensation in the presence of an oxidizing agent. This copolymer has the following general formula (6)

(In the formula, R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group, and m and n each independently represents an integer of 6 or more and 150 or less.
It is preferable that it is a copolymer represented by this. In the formula (6), preferred R ₁ and R ₂
And R ₃ each independently represents a hydrogen atom, a methyl group, an ethyl group or a phenyl group.
The composite of the present invention is produced as a composite of a copolymer having a quinoxaline structural unit and a benzimidazole structural unit and a conductive carbon material by synthesizing the copolymer in the presence of a conductive carbon material. The Here, the composite means a generic name of a state in which the surface of the conductive carbon material is covered with the copolymer or the conductive carbon material and the copolymer are mixed.

As a method of dehydration copolycondensation, a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit is synthesized by adding all raw materials at once and performing copolycondensation in the presence of an oxidizing agent. Can do.

In addition, after reacting a tetracarbonyl compound and a tetraamine compound in advance to form an oligomer having a quinoxaline skeleton, a dialdehyde compound is co-condensed in the presence of an oxidizing agent to form a quinoxaline structural unit and a benzimidazole structural unit. You may synthesize | combine the containing copolymer. In this case, an excess amount of the tetraamine compound may be used with respect to the tetracarbonyl compound in the reaction of the tetracarbonyl compound and the tetraamine compound.

Further, after reacting a dialdehyde compound and a tetraamine compound in the presence of an oxidizing agent to form an oligomer having a benzimidazole skeleton, the tetraamine compound is co-condensed to form a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit. A polymer may be synthesized. In this case, an excess amount of the tetraamine compound relative to the dialdehyde compound may be used in the reaction between the dialdehyde compound and the tetraamine compound.

In addition, when dehydrating copolycondensation is performed in the presence of a conductive carbon material for the purpose of obtaining a composite according to the present invention, the reaction can be performed in the same manner as in the case of synthesizing the copolymer. At this time, the conductive carbon material can be added at any stage.

That is, when producing a composite of the copolymer and a conductive carbon material, the conductive carbon material is added when performing dehydration copolycondensation in the presence of an oxidizing agent by adding all raw materials at once. By doing so, a composite in which the surface of the conductive carbon material is coated with a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit can be produced.

As a second reaction mode, a tetracarbonyl compound and a tetraamine compound are reacted first to form an oligomer having a quinoxaline skeleton, and then the dialdehyde compound is dehydrated in the presence of an oxidizing agent and a conductive carbon material. By performing condensation polymerization, a composite in which a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit is coated on the surface of a conductive carbon material can be produced. In this case, an excess amount of the tetraamine compound may be used with respect to the tetracarbonyl compound in the reaction of the tetracarbonyl compound and the tetraamine compound.

As a third reaction mode, a dialdehyde compound and a tetraamine compound are reacted in the presence of an oxidizing agent to form an oligomer having a benzimidazole skeleton, and then a conductive carbon material is added to dehydrate the tetracarbonyl compound. You may synthesize | combine the composite_body | complex which coat | covered the surface of the conductive carbon material with the copolymer containing a quinoxaline structural unit and a benzimidazole structural unit by making it polycondensate. In this case, an excess amount of the tetraamine compound relative to the dialdehyde compound may be used in the reaction between the dialdehyde compound and the tetraamine compound.

Further, as a fourth reaction mode, a tetracarbonyl compound and a tetraamine compound are first reacted in the presence of a conductive carbon material to coat an oligomer having a quinoxaline skeleton on the surface of the conductive carbon material, and then a dialdehyde compound is added. By dehydrating copolycondensation in the presence of an oxidizing agent, a composite in which a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit is coated on the surface of a conductive carbon material can be synthesized. In this case, an excess amount of the tetraamine compound may be used with respect to the tetracarbonyl compound in the reaction of the tetracarbonyl compound and the tetraamine compound.

Furthermore, as a fifth reaction mode, after reacting a dialdehyde compound and a tetraamine compound together with an oxidizing agent in the presence of a conductive carbon material to coat an oligomer having a benzimidazole skeleton on the surface of the conductive carbon material, tetracarbonyl A compound in which a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit is coated on the surface of a conductive carbon material may be synthesized by dehydrating copolycondensation of the compound. In this case, an excess amount of the tetraamine compound relative to the dialdehyde compound may be used in the reaction between the dialdehyde compound and the tetraamine compound.

<Each component>
The tetracarbonyl compound used in the present invention may be a compound having two 1,2-diketone structures in the molecule, preferably an aromatic carbonyl compound, more preferably,
Following formula (4)

A tetracarbonyl compound represented by the formula (wherein R ₂ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group) can be used. In the formula (4), R ₂ is preferably a hydrogen atom, a methyl group, an ethyl group or a phenyl group. A specific example is 1
, 4-bis- (phenylglyoxyloyl) benzene, 1,3-bis- (phenylglyoxyloyl) benzene and its alkyl, alkoxy, halogen, sulfonic acid, and nitro group-substituted products.

The dialdehyde compound used in the present invention is preferably an aromatic dialdehyde compound, more preferably the following formula (5).

(In the formula, R ₃ represents a hydrogen atom, an alkyl group, an aryl group, or an alkoxy group). In the formula (5), preferred R ₃
Is a hydrogen atom, a methyl group, an ethyl group or a phenyl group. Specific examples thereof include terephthalaldehyde and isophthalaldehyde.

The tetraamine compound used in the present invention has a 1,2-diamine structure in the molecule.
The aromatic amine compound may be any one having the following general formula (1)

A tetraamine compound represented by the formula (wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group) is preferably used. In the formula (1), preferred R ₁ is
A hydrogen atom, a methyl group, an ethyl group or a phenyl group; Specific examples of this are 3, 3'-
Examples include diaminobenzidine and its alkyl, alkoxy, halogen, sulfonic acid, and nitro group-substituted products.

The oxidizing agent used in the present invention may be any oxidizing agent that can oxidize a benzylidene type compound obtained by dehydration reaction of an aldehyde and 1,2-diamine to form an imidazole ring. Air is preferably used as a suitable oxidizing agent. In addition, oxygen can also be used.

The conductive carbon material combined with the copolymer containing the quinoxaline structural unit and the benzimidazole structural unit of the present invention is mainly composed of a single carbon, and among them, the conductivity is high,
Those having a large specific surface area and a small particle size are preferred. However, if the specific surface area is too large and / or the particle size is too small, the activity becomes high and side reactions are likely to occur, and the bulk becomes high and the energy density per volume (Wh / L) may be reduced. Therefore, as these preferable ranges, the electrical conductivity is 0.1 S / cm or more at room temperature, and the specific surface area is 1000 or more 1 by the BET method.
00000 m ² / g or less, and the average particle size is 1 μm or more and 20 μm or less. Here, the average particle size refers to the secondary agglomerated particle size measured by a centrifugal sedimentation type particle size distribution meter.

Specific examples of these conductive carbon materials include carbon blacks such as ketjen black and acetylene black, activated carbons such as coconut shell activated carbon, carbon fibers such as air-layer carbon fiber, carbon fiber and carbon nanotube, natural graphite, artificial graphite Examples thereof include graphites such as graphite.
Of these, ketjen black is preferably used.

The addition amount of the conductive carbon material is preferably in the range of 5/95 to 50/50, particularly preferably 8/92 to 30/70, with respect to the produced copolymer. If the amount of the conductive carbon material added is too small, the coating amount of the polymer is too large and the electrical conductivity is lowered, which is not preferable. If too much conductive carbon material is added, it becomes bulky and difficult to mold, and the amount of the copolymer containing the quinoxaline structural unit, which is the active substance in the electrode, as a repeating structure decreases, resulting in a volume per composite. In addition, the battery capacity per weight is not preferable.

<Composite with polymerization and conductive carbon material>
The combination with polymerization and conductive carbon material will be described.
General formula (2) of the present invention

(In the formula, R ₁ and R ₄ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group.)
A quinoxaline structural unit represented by the general formula (3)

(In the formula, R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group.)
A composite of a copolymer containing a benzimidazole structural unit represented by
Tetracarbonyl compounds and dialdehyde compounds having two 1,2-diketone structures in the molecule and the general formula (1)

(Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group) and is synthesized by dehydrating copolycondensation with a tetraamine compound represented by the following formula in the presence of a conductive carbon material and an oxidizing agent. The

The reaction temperature cannot be generally limited depending on the type of monomer used and the solvent, but it is generally carried out near the reflux temperature of the solvent used.
The reaction time cannot be generally limited depending on the type of monomer used and the solvent, but is dehydration polycondensation, and at least one hour is required for polymerization. The preferred range is 5 hours or more and 100
Within 25 hours, more preferably within 25 hours and within 100 hours, particularly preferably between 30 hours and 70 hours.

As the monomer concentration in the solvent during polymerization, the total mass of the tetracarbonyl compound, the dialdehyde compound, and the tetraamine compound is preferably 5% by mass or more and 40% by mass or less, and particularly preferably 8% by mass or more and 30% by mass or less. If the monomer concentration is too low, polymerization does not proceed easily and the molecular weight does not increase. If the monomer concentration is too high, the viscosity of the polymerization solution will increase, making mixing difficult.
The coating on the conductive carbon material becomes non-uniform. Moreover, polymer precipitation occurs early and the molecular weight is difficult to increase.

The solvent to be used is not particularly limited as long as the monomer to be used is easily dissolved and does not react. Examples thereof include nitrogen-containing polar solvents such as N, N-dimethylformamide (DMF) and N-methylpyrrolidone, and ethers such as tetrahydrofuran, 1,2-dimethoxyethane, triethylene glycol dimethyl ether and tetraethylene glycol dimethyl ether. Moreover, about reaction temperature, it is 100 degreeC or more and 150 degrees C or less normally. For example, when the solvent is N, N-dimethylformamide, the reaction is performed at 130 ° C. or higher and 150 ° C. or lower.

After the reaction of dehydration copolycondensation, the reaction mixture is preferably filtered and then washed with a solvent to remove impurities, solvent, and unreacted raw materials. Here, as the solvent used for washing, for example, alcohol is preferably used because it is inexpensive, safe in production, and can be used without dissolving the product.

The molecular weight of the composite in the present invention will be described. The higher the molecular weight of the copolymer containing the quinoxaline structural unit and the benzimidazole structural unit, the better the durability, and the fewer side reactions caused by the residual monomer functional groups. A preferred molecular weight range is 5% by weight or less of a low molecular weight material having a weight average molecular weight of 20,000 or more, more preferably 40,000 or more, and particularly preferably less than 5,000 in absolute molecular weight measurement by a light scattering method.

The pulverization of the composite in the present invention will be described. A composite in which a copolymer containing a quinoxaline structural unit and a benzimidazole structural unit is coated on the surface of a conductive carbon material is preferably pulverized to an appropriate particle size before being used as an electrode. As a preferable particle size, the average particle size is 1 μm or more and 20 μm or less and the maximum particle size is 200 μm or less, more preferably, the average particle size is 1 μm or more and 15 μm or less and the maximum particle size is 100 μm or less. Here, the average particle size refers to the secondary agglomerated particle size measured by a centrifugal sedimentation type particle size distribution meter. The pulverization method is not particularly limited, but a wet method such as a bead mill, a pulverizer, a bantam mill, a ball mill,
Examples include dry methods such as jet mills and pin mills.

The conductivity in the present invention will be described. The quinoxaline structure and the benzimidazole copolymer need to be electrically conductive when used as an electrode. Therefore, it is combined with a conductive carbon material. The conductivity in this case is preferably 0.1 S / cm or more, and more preferably 0.2 S / cm or more, as the volume conductivity at 25 ° C.

Hereinafter, the present invention will be described in detail by way of typical examples. These are merely examples for explanation, and the present invention is not limited to these.
Example 1 Synthesis of Polyphenylquinoxaline / Polybenzimidazole Copolymer / Ketjen Black Composite (PPQ / PBI / KB) 1
The reaction was carried out according to the following scheme.

That is, N, N-dimethylformamide (DMF) 600 g, bisbenzyl (BBZ) 24.16 g (71 mmol) in a 1 L glass separable flask equipped with a stirring blade and a cooling tube.
), 4.83 g (36 mmol) of terephthalaldehyde (TPAL) and 23.66 g (107 mmol) of 3,3′-diaminobenzidine (DABZ) were added, and the mixture was stirred at room temperature under a nitrogen atmosphere for 10 minutes. Thereafter, 18.50 g of ketjen black (Ketjen black EC600JD was used, hereinafter abbreviated as “KB”) was added, and the mixture was reacted at 130 ° C. for 20 hours while introducing air by bubbling.

The obtained black precipitate was filtered, washed with methanol, and then vacuum-dried at 130 ° C. for 12 hours to obtain 63.81 g of PPQ / PBI / KB black powder 1. The elemental analysis values (wt%) of this powder are C: 84.35, H: 3.26, N: 9.14, and the composite ratio is PPQ:
PBI: KB = 54: 17: 29 was calculated. The absolute molecular weight (weight average) by light scattering from GPC using hexafluoroisopropanol (HFIP) as an eluent is 270.
00.

Example 2 Synthesis of Polyphenylquinoxaline / Polybenzimidazole Copolymer / Ketjen Black Composite (PPQ · PBI · KB) 2
BBZ 27.49 g (80.3 mmol), TPAL 2.78 g (20.7 mmol)
l) 63.79 g of PPQ / PBI / KB black powder 2 was obtained in the same manner as in Example 1 except that 22.43 g (101.0 mmol) of DABZ was used. The elemental analysis values (wt%) of this powder were C: 85.96, H: 3.17, N: 8.84, and the composite ratio was PPQ.
: PBI: KB = 61: 10: 29. Also, the absolute molecular weight (weight average) by light scattering from GPC using hexafluoroisopropanol (HFIP) as an eluent is 32.
000.

Example 3 Synthesis of Polyphenylquinoxaline / Polybenzimidazole Copolymer / Ketjen Black Composite (PPQ · PBI · KB) 3
63.20 g of PPQ / PBI / KB black powder 3 was obtained in the same manner as in Example 1 except that 4.83 g (36 mmol) of isophthalaldehyde (IPAL) was used instead of TPAL. Elemental analysis values (wt%) of this powder were C: 84.30, H: 3.24, N: 9
. The composite ratio was calculated as PPQ: PBI: KB = 53: 18: 29. The absolute molecular weight (weight average) was 27000.

[Comparative Example 1: Polyphenylquinoxaline / Ketjen black composite (PPQ · KB)
Synthesis of 4]
34.24 g (100 mmol) of BBZ and 22.23 g (100 mmol) of DABZ
), And without using TPAL, 68.61 g of PPQ · KB black powder 4 was obtained by the same method as in Example 1 except that polymerization was performed in a nitrogen atmosphere instead of air bubbling. The elemental analysis values (wt%) of this powder were C: 86.75, H: 3.30, N: 8.61, and the composite ratio was calculated as PPQ: KB = 76: 24. The absolute molecular weight (weight average) is 270.
00.

[Examples 4 to 6, Comparative Example 2: Conductivity measurement of composite]
Each of the black powders 1 to 4 obtained in Examples 1 to 3 and Comparative Example 1 was vacuum-dried at 100 ° C. for 14 hours, and then weighed about 0.9 g in a dry air atmosphere to obtain a Teflon binder (POLYFLON:
It was ground with an analytical mill (20000 rpm) together with about 0.1 g of Daikin Industries, Ltd. About 0.1 g of this pulverized product was pressure-molded with a tablet molding machine having a diameter of 13 mm to obtain pellet electrodes corresponding to the composites 5-8. The conductivity of these pellet electrodes was measured by a 4-terminal direct current method. The results are shown in Table 1.

In Table 1 above, the composites and pellet electrodes used in Examples 4 to 6 and Comparative Example 2 correspond to composites 5 to 8 and pellet electrodes 5 to 8, respectively.
[Example 7: Synthesis of polyaniline (PAn)]
Stir 0.22 mol of aniline in 500 ml of 1N hydrochloric acid in the presence of 0.05 mol ammonium persulfate for 1 hour. The precipitate obtained by changing the reaction solution to blue-green was filtered through a glass filter, washed with 1N hydrochloric acid, and then vacuum-dried at 100 ° C. for 14 hours to obtain 12 g of a blue-green target product. From the analysis of deep purple elemental element obtained by neutralizing the target product with an aqueous ammonia solution, the target product was estimated to have a polyaniline structure. From the result of GPC in NMP (N-methylpyrrolidone), the molecular weight (in terms of PMMA) was about 50,000 in terms of number average and about 120,000 in terms of weight average.

[Example 8: Production of PAn positive electrode]
85: 7 of this PAn powder and acetylene black (AB: manufactured by Denki Kagaku), VGCF (registered trademark, vapor grown carbon fiber manufactured by Showa Denko), polyvinylidene fluoride (PVDF: manufactured by Kuraray)
An excess of NMP (N-methylpyrrolidone) was added to the 1: 7 mixture to obtain a gel composition. After applying this composition onto a platinum mesh current collector 1 × 1 cm on a platinum plate with lead wires, 1 ton
Press-molded and vacuum-dried at 80 ° C for 8 hours, so that the PAn electrode (average 200 mg)
50 were created.

[Examples 9 to 11, Comparative Example 3]
Various composite electrodes produced in Examples 4 to 6 and Comparative Example 2 were pressure-molded into a platinum mesh on a platinum plate with lead wires, and this was used as a working electrode, platinum as a counter electrode, and a silver / silver chloride electrode as a reference electrode, Assembling a beaker cell with 40% sulfuric acid as an electrolyte, and changing the capacity of various composite electrodes to 0.5V to -0.2V under charge / discharge conditions
It was measured at 1 mA.

Table 2 shows the discharge capacity results per gram of PPQ after 10 cycles.
In the case of 90 ° C., Comparative Example 3 showed strong yellow coloring in the electrolyte solution after the end of the cycle.
No coloration was observed in ˜11, and it was confirmed that the heat resistance was excellent.

[Examples 12 to 14, Comparative Example 4: Production of Proton Transfer Type Secondary Battery]
The PAn positive electrode produced in Example 8, followed by a 1 mm thick glass fiber separator (1.
2 × 1.2 cm). Next, various composite electrodes 5 to 8 manufactured in Examples 4 to 6 and Comparative Example 2 formed by pressure forming on a platinum net on a platinum plate with lead wires were stacked. After pressurizing and adhering these laminates, both ends were fixed with a polyimide tape (Kapton tape). Then, this laminate is put in an aluminum laminate outer package and taken out to prevent the two platinum lead wires from being short-circuited. Next, 20% sulfuric acid aqueous solution is injected into the exterior body as an electrolytic solution, and the exterior body is brought into close contact while extracting excess sulfuric acid aqueous solution under reduced pressure, and then sealed by heating and fusion, and three types of PPQ, PBI, and KB. Composite PAn secondary battery (each n = 3, 9 in total) and one type of PPQ
A KB composite PAn secondary battery (n = 3, three in total) was prepared.

When this battery was charged / discharged at 25 ° C., operating voltage 0-0.8 V, current 2 mA, 10 mA, a clear charge / discharge behavior was shown, and the maximum discharge capacity was as shown in Table 3.

Claims (23)

General formula (2)
(Wherein R ₁ and R ₄ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group) and a quinoxaline structural unit represented by the general formula (3)
(Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group), a copolymer containing a benzimidazole structural unit represented by:
Conductive carbon materials;
And composites. The copolymer according to claim 1 has the following general formula (6)
(Wherein R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group, and m and n each independently represents an integer of 6 to 150). A composite comprising a phenylquinoxaline structural unit and a phenylbenzimidazole structural unit represented by: Tetracarbonyl compounds having two 1,2-diketone structures in the molecule, dialdehyde compounds and general formula (1)
(Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group, or an alkoxy group). A dehydration copolycondensation polymerization is performed in the presence of an oxidizing agent and a conductive carbon material. ,
General formula (2)
(Wherein R ₁ and R ₄ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group) and a quinoxaline structural unit represented by the general formula (3)
(Wherein R ₁ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group). A method for producing a composite of a copolymer containing a benzimidazole structural unit represented by The tetracarbonyl compound is represented by the following general formula (4):
(Wherein R ₂ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group),
The dialdehyde compound is represented by the following general formula (5)
(Wherein R ₃ represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group), and
The copolymer is represented by the following general formula (6)
(In the formula, R ₁ , R ₂ and R ₃ each independently represents a hydrogen atom, an alkyl group, an aryl group or an alkoxy group, and m and n each independently represents an integer of 6 or more and 150 or less.
The production method according to claim 3, wherein the copolymer is represented by the following formula: The tetracarbonyl compound is reacted in advance with an excess of the tetraamine compound with respect to the tetracarbonyl compound to form a mixture of an oligomer having a quinoxaline skeleton and a tetraamine compound, and then the dialdehyde compound is converted to conductive carbon. The production method according to claim 3 or 4, wherein the dehydration copolycondensation is carried out by reacting in the presence of a material and an oxidizing agent. After the dialdehyde compound and an excess amount of the tetraamine compound with respect to the dialdehyde compound are reacted in advance in the presence of an oxidizing agent to form a mixture of an oligomer having a phenylbenzimidazole skeleton and a tetraamine compound, 5. The production method according to claim 3, wherein dehydration copolycondensation polymerization is performed by reacting the tetracarbonyl compound in the presence of a conductive carbon material. A conductive carbon material coated with an oligomer having a quinoxaline skeleton and a tetraamine compound obtained by previously reacting the tetracarbonyl compound and an excess of the tetraamine compound with respect to the tetracarbonyl compound in the presence of a conductive carbon material. 5. The production method according to claim 3, wherein after the mixture is formed, the dialdehyde compound is reacted in the presence of an oxidizing agent to perform dehydration copolycondensation. Conductive carbon coated with an oligomer having a phenylbenzimidazole skeleton by previously reacting the dialdehyde compound and an excess of the tetraamine compound with respect to the dialdehyde compound in the presence of a conductive carbon material and an oxidizing agent. The method according to claim 3 or 4, wherein after the mixture of the material and the tetraamine compound is formed, the tetracarbonyl compound is reacted to perform dehydration copolycondensation. Polymerization is performed in presence of a solvent, The manufacturing method in any one of Claims 3-8 characterized by the above-mentioned. 10. The production method according to claim 9, wherein the concentration of the total monomer composed of the tetracarbonyl compound, the dialdehyde compound, and the tetraamine compound in the solvent at the start of polymerization is 5% by mass or more and 40% by mass or less. . The method according to claim 9 or 10, wherein the solvent is N, N-dimethylformamide. The production method according to claim 9, wherein the polymerization temperature is 100 ° C. or higher and 150 ° C. or lower. The tetracarbonyl compound is an aromatic tetracarbonyl compound.
The manufacturing method in any one of. The production method according to claim 3, wherein the tetracarbonyl compound is bis- (phenylglyoxyloyl) benzene. The production method according to claim 3, wherein the dialdehyde compound is an aromatic dialdehyde compound. The method according to any one of claims 3 to 14, wherein the dialdehyde compound is either terephthalaldehyde or isophthalaldehyde. The manufacturing method according to claim 3, wherein the tetraamine compound is an aromatic amine compound. The production method according to claim 3, wherein the tetraamine compound is 3,3′-diaminobenzidine.   The manufacturing method according to claim 3, wherein the oxidizing agent is air. The manufacturing method according to claim 3, wherein the conductive carbon material is ketjen black. The method according to any one of claims 3 to 20, further comprising, after the reaction of dehydration copolycondensation, the step of washing the reaction mixture with an alcohol-based solvent after filtration.   The composite obtained by the manufacturing method in any one of Claims 3-21. A proton transfer battery using the composite according to any one of claims 1, 2, and 22 as an electrode.