JPS63215717A - Production of electroconductive material - Google Patents

Abstract

PURPOSE:To make it possible to produce in an economically advantageous manner an electroconductive material of a high bulk density, by adding a salt to the system in the polymerization of a pyrrole compound in the presence of a specified mixed oxidizing agent. CONSTITUTION:In the production of a pyrrole polymer by reacting a pyrrole compound (e.g., pyrrole) in the presence of an oxidizing agent comprising a cupric compound [e.g., Cu(BF4)2] and a nitrile compound (e.g., acetonitrile), a salt is added to this reaction system. Examples of said salts include organic and inorganic salts and double salts which are soluble in said reaction system containing said oxidizing agent and are easily ionizable in this reaction system (e.g., LiBF4). The obtained electroconductive material can be easily handled because of its increased bulk density, and it can be produced in an economically advantageous manner because production and molding apparatuses can be reduced in size.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is an improvement in the method of reacting a pyrrole compound in the presence of an oxidizing agent in which a cupric compound and a nitrile compound coexist. This invention relates to a method for producing a conductive material in which the above reaction is carried out in the presence of a salt.

<Prior art> Polymers with conjugated double bonds in their main chains, such as polyacetylene, polyparaphenylene, polythiophene, polypyrrole, polyparaphenylene vinylene, polyaniline, etc., are arsenic pentafluoride.

Antimony pentafluoride, iodine, bromine, sulfur trioxide, n-
It has been known that when treated with a P-type or N-type doping agent such as butyllithium or sodium naphthalene, the electrical conductivity is significantly improved and the material changes from an insulator to a semiconductor to a conductor. These conductive materials are also called conductive polymers, and are obtained in the form of powder, grains, lumps, or films, and can be used as they are or after being molded, depending on the purpose.
Antistatic material, electromagnetic shielding material.

Functional elements such as photoelectric conversion elements (electronic-optical functional elements), optical memory (holographic memory) and various sensors, display elements (electrochromism), switches, various hybrid materials (transparent conductive films, etc.), various terminal devices, Applications to a wide range of fields such as storage batteries are being considered.

Among the various conductive polymers mentioned above, polythiophene, polypyrrole, polyaniline, etc. have better stability in air than polyacetylene, have extremely little oxidative deterioration, and are easy to handle conductive polymers. Studies are being carried out on various applications that take advantage of this.

Conventionally, methods for producing polythiophene, polypyrrole yaborianiline, etc. include: (1) electrochemical oxidative polymerization (electrolytic polymerization) of conjugated compounds such as thiophene compounds, pyrrole compounds, or aniline compounds; A method of chemically oxidatively polymerizing these conjugated compounds using an oxidizing agent is known.

In method (2), polythiophene, polypyrrole, or polyaniline is deposited in a film form on the anode used for electrolytic polymerization, and after the deposition is peeled off from the anode, a film of polythiophene, polypyrrole, or polyaniline is obtained. In addition, method (■) uses peroxides such as potassium persulfate and ammonium persulfate, acids such as nitric acid, sulfuric acid, or chromic acid, and oxidizing agents such as Lewis acids such as ferric chloride, ruthenium chloride, tungsten chloride, or molybdenum chloride. use. However, the size of the polythiophene, polypyrrole, polyaniline, etc. obtained by the above method (■) is restricted by the dimensions of the electrolytic anode plate, which severely limits mass production, making it somewhat difficult to use industrially, and making it difficult to manufacture. There are drawbacks such as the complicated method and loss of 1 to high. Although the method (2) does not have these drawbacks, it does have the drawbacks that the electrical conductivity of the produced conductive polymer is low, which limits its application to various uses and narrows its scope of application. Furthermore, in the method (2), ferric perchlorate is used as an oxidizing agent in an organic solvent (for example, MOL, cry
st, LiQ, CrVSt, magazine, 1985 vo
(pp. 149-153 of IIA), polypyrrole in powder form has been obtained, but since the solubility of ferric perchlorate in an organic solvent is lower than that in an aqueous solution, it is difficult to mass-produce it. In addition to being disadvantageous due to manufacturing constraints, the resulting polypyrrole has a low electrical conductivity because the concentration of the doping agent in the solvent decreases by the amount of the decrease in solubility. In addition, it also has the disadvantage that it is necessary to take various safety measures during the manufacturing process because it handles organic solvents that have a high risk of explosion.

On the other hand, JP-A No. 60-58430 proposes a method for producing conductive powdery pyrrole polymers in which pyrroles are treated with an oxygen-containing oxidizing agent in the presence of a conductive salt in a solution. has been done.

However, in this method, peroxides such as peroxo acids or their salts or hydrogen peroxide are used as the above-mentioned oxygen-containing oxidizing agent, so there is a risk of explosion, and the storage, handling, and reaction of these peroxides is problematic. It is necessary to be very careful about abnormalities, and especially when mass-produced on an industrial scale, there are extremely serious inconveniences in terms of handling safety.

The present inventor conducted research to obtain a conductive material that does not have the above drawbacks and disadvantages, is stable in air, has a high reaction rate, produces a large amount, is easy to manufacture, and has high electrical conductivity. did. As a result, they learned that the desired conductive material could be produced by oxidative polymerization of the above conjugated compound using an oxidizing agent containing a cupric compound and a nitrile compound. It was previously proposed (Patent Application No. 61-215298 @) as a method for manufacturing .

<Problems to be solved by the invention> Although the method of Japanese Patent Application No. 61-215296 is an extremely safe WA manufacturing method, as mentioned above, the method uses an oxidizing agent in which a cupric compound and a nitrile compound coexist. When the above-mentioned conductive material is obtained by oxidative polymerization of a pyrrole-based compound using a chisel, the bulk density of this conductive material is small. However, there is a problem in that large-sized equipment is required, and the inconvenience of handling makes it impossible to produce economically advantageously.

<Means for Solving the Problems> Accordingly, the present invention produces a pyrrole polymer by reacting a pyrrole compound in the presence of an oxidizing agent in which a cupric compound and a nitrile compound coexist. In the method, the gist of the method is to allow a salt to coexist during the reaction.

The cupric compound used in the present invention includes, for example, the general formula % formula % (1) (wherein, X is c, eo -, BF4-1AsF -
1pF -1SbF6-1CH3C6H4SO3-1C
F3S03-1ZrF6-1T! F6- or Si
F6-, and m represents an integer of 1 to 2. ) are mentioned.

Specifically, as such a cupric compound, Cu (
CJ204)2, Cu(BF4)2, Cu
(PF6)2, Cu (ASF6 >2, Cu (
SbF6 )2, CIJ (CH3C6H4303>2, Cu (CF3
SO3>2, CuZrFe, CuTiF6, C
uS i F6, and these are usually used as compounds with water of crystallization or as aqueous solutions.

The nitrile compounds used in the present invention include, for example, the general formula % formula % (2 (wherein R represents an alkyl group, alkenyl group, or aryl group that may have a substituent, and n is 1 to represents an integer of 3).

In the nitrile compound represented by the above general formula (2), R is a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a 5ec-butyl group, a tert-butyl group, a vinyl group, Methylvinyl group, dimethylvinyl group, ethylvinyl group, diethylvinyl group,
n-propylvinyl group, n-butylvinyl group, phenylvinyl group, naphthylvinyl group, hydroxymethyl group, hydroxyethyl group, hydroxypropyl group, hydroxybutyl group, methoxymethyl group, methoxyethyl group, methoxypropyl group, ethoxymethyl group , ethoxyethyl group, cyanmethyl group, cyanoethyl group, cyanopropyl group, cyanobutyl group, cyanopentyl group, cyanohexyl group, carboxymethyl group, carboxyethyl group, carboxypropyl group, phenyl group, naphthyl group, tolyl group, hydroxyphenyl group group, hydroxynaphthyl group, methoxyphenyl group, ethoxyphenyl group, methoxynaphthyl group, cyanophenyl group, dicyanophenyl group, cyanotolyl group, dicyanotolyl group, cyanonaphthyl group,
Represents a carboxyphenyl group, carboxytolyl group, etc. Specifically, such nitrile compounds include acetonitrile, n-propionitrile, isopropionitrile, n-butyronitrile, isobutyronitrile, tert-butyronitrile, acrylonitrile, methylacrylonitrile, ethyl acrylonitrile, phenyl acrylonitrile, Acetone cyanohydrin, methylene cyanohydrin, ethylene cyanohydrin, propylene cyanohydrin, methoxyacetonitrile, ethoxyacetonitrile, methoxypropionitrile, malondinitrile, adiponitrile, cyanoacetic acid, cyanopropionic acid, cyanobutyric acid, benzonitrile, naphthonitrile, methylbenzonitrile, hydroxybenzonitrile,
Examples include phthalonitrile, tricyanobenzene, methoxybenzonitrile, carboxybenzonitrile and the like.

Examples of the pyrrole compound used in the present invention include (wherein R and R2 represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an allyloxy group, an amino group, an alkylamino group, or an arylamino group). Examples include pyrrole compounds represented by:

Among the pyrrole compounds represented by the general formula (3) above, pyrrole compounds having no substituents at the 2 and 5 positions of the five-membered ring structure are preferred. In addition, for details, R1, R2
is a hydrogen atom, a methyl group, an ethyl group, an n-propyl group,
Isopropyl group, n-butyl group, isobutyl group, 5ec
-Butyl group, tert-butyl group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, phenyl group, tolyl group, naphthyl group, phenoxy group, methylphenoxy group, naphthoxy group, amino group , dimethylamino group, diethylamino group, phenylamino group, diphenylamino group, methylphenylamino group,
Represents a phenylnaphthylamino group.

In addition, as the above-mentioned pyrrole compounds, specifically, pyrrole, N-methylpyrrole, N-ethylpyrrole, N-
Phenylpyrrole, N-naphthylpyrrole, N-methyl-3-methylpyrrole, N-methyl-3-ethylpyrrole, N-phenyl-3-methylpyrrole, N-phenyl-3-ethylpyrrole, 3-methylpyrrole, 3 -ethylpyrrole, 3-n-propylpyrrole, 3-1so
-propylpyrrole, 3-n-butylpyrrole, 3-methoxypyrrole, 3-ethoxypyrrole, 3-n-propoxypyrrole, 3-n-butoxypyrrole, 3-phenylpyrrole, 3-tolylpyrrole, 3-naphthylpyrrole, Examples include 3-phenoxypyrrole, 3-methylphenoxypyrrole, 3-aminopyrrole, 3-dimethylaminopyrrole, 3-diethylaminopyrrole, 3-diphenylaminopyrrole, 3-methylphenylaminopyrrole, 3-phenylnaphthylaminopyrrole, etc. .

In the present invention, a single or two or more different pyrrole compounds are used in combination with a single or two or more different cupric compounds and a single or different two or more nitrile compounds. It can be reacted with an oxidizing agent.

The amount of the cupric compound represented by the general formula (1) to be used is 0.01 to 100 times, preferably 0.1 to 50 times, per mole of the conjugated compound.

Further, the nitrile compound represented by the general formula (2) is used together with the cupric compound, and examples of the method for using it include the following method.

1) After allowing a nitrile compound and a cupric compound to coexist in advance, they are allowed to interact with a pyrrole compound.

2) A cupric compound is allowed to act on a system in which a pyrrole compound and a nitrile compound coexist.

3) A nitrile compound is allowed to act on a system in which a pyrrole compound and a cupric compound coexist.

4) A system in which a cupric compound and a 21-lyl compound coexist is removed from the system in which a pyrrole compound and a nitrile compound coexist.

5) A reaction product of a cupric compound and a nitrile compound is isolated in advance and allowed to react with a pyrrole compound.

The coexistence of such a nitrile compound significantly accelerates the reaction between the pyrrole compound and the oxidizing agent, so that the oxidative polymerization reaction can easily proceed even in a system where substantially no oxidative polymerization reaction occurs.

Further, the amount of the nitrile compound represented by general formula (2) to be used is 0.01 to io, o to 1 mole of the cupric compound.
oo times the mole, preferably 0.1 to 1,000 times the mole. If the nitrile compound is a liquid substance, it can be used as a reaction solvent, or if it is a solid substance, any solvent can be used, such as water, alcoholic solvents such as methanol and ethanol, tetrahydrofuran, dioxane, and benzene. , toluene, dichloromethane, dichloroethane, acetic acid, and other common organic solvents.

The salt used in the present invention is an organic or inorganic salt or double salt that is soluble in the reaction system containing the oxidizing agent and easily dissociates into ions in this reaction system, and has the general formula % formula % (4) (formula (wherein, M is an alkali metal or a quaternary alkylammonium group, X is a perchlorate ion, a fluorine metal anion, or a sulfonic acid anion, and a represents an integer of 1 to 2.) Salt is an example.

Specifically, such salts include LiCλ04, LiBF4, LiAsF6, LiP
F6, LiSbF6, Li2ZrF6, Li2TiF
6, Li2SiF6, L! 2810Cffl 10. CH3C6H430
3L! , CF3803 Li, NaC, 204, Na
BF4, NaASF6, NaPF6, Na5t)F
6, Na2 Zr F6 , Na2 T ! F6, N
a2S i F6, Na2B10CJ210°CH3
C6H4SO3Na, CF3303 Na, Bu 4
N CA O4, B! 4 N B F 4, Bu4
NAsF6, Bu4NPF6, Bu4NSb
F6, (Bu4N)2ZrF6, (BLI41
', I>2T i F(3, (B LJ4 N>2
3! F6, (Bu4N)2 E3ioc-'1o,
CH3C6H4303NBu4, CF35O3NBu4, Et4 NCJ104, E j
4 NBF4, E t4 NAs F6, Li4 N
PF6, Ej4NSbF6, (Et4N)2ZrF
6, (E j4 N>2 T! F6, (E t4 N)2 S i F6, (E t4 N>2810C rabbit 10・CH3C6H4S 03 N E ta, CF380
Examples include 3NE14.

Further, the amount of the salt represented by the general formula (4) to be used is o, oi to 100mil10 per mole of the above pyrrole compound.
It is 0 times mole or 0.1 to 50 times mole. and,
Examples of methods for using this salt include the following methods.

1) Coexist with a nitrile compound in advance and add it to the cupric compound or pyrrole compound.

2) Coexist with a cupric compound in advance and add it to the nitrile compound or pyrrole compound.

The subsequent method of use follows the method of using the nitrile compound and cupric compound described above.

The reaction temperature is -50°C to 150°C, preferably -22°C.
0'C to 100C. The reaction time is related to the reaction temperature, but is usually 0.5 to 200 hours, preferably 1.0 to 1
It is 00 hours.

The reaction between the cupric compound represented by the general formula (1) and the copper compound represented by the general formula (3) can be carried out in any phase including solid phase, liquid phase, and gas phase. However, it is preferable to carry out the reaction in the liquid phase.

The reaction product is a dark brown to black powdery material. Also,
In the reaction in the presence of the above solvent, after the reaction is completed, the solvent is removed by a conventional method, and the reaction product is washed and purified several times with a liquid nitrile compound, such as acetonitrile, propionitrile, etc., to produce a by-product. It is preferable to dissolve and remove the cuprous compound because a product with higher conductivity can be obtained.

<Function> By using the above-mentioned means, the bulk density of the resulting conductive material increases, making it easier to handle and making it possible to downsize the manufacturing and molding equipment. The material can now be manufactured economically.

<Example> The present invention will be specifically explained below with reference to Examples.

Example 1 Pyrrole 2.68G (
0.04 mol) and LiBF47.5og<O,O
a mol) and 150 ml of acetonitrile, and while stirring under a nitrogen atmosphere, add 15 to 20
63.2 g (0,12-El) of a 45% Cu(BF4)2 aqueous solution prepared in advance at
The mixture with mN was added dropwise over 10 minutes.

As the mixture was added, heat generation was observed, and the reaction liquid immediately turned black, powdery solids precipitated in the reaction liquid, and the reaction liquid took on the form of a slurry. After stirring for 6 hours, the reactant was separated into a furnace to obtain a black powdery substance mixed with white crystalline substances.

When this was washed 5 times with acetonitrile isomrho, the white crystalline substance was removed, and when it was dried under reduced pressure at a temperature of 60°C, 3.2 g of a black powdery substance was obtained.

Elemental analysis of this black powder substance revealed that C48, 41
%, 83.01%, N 14.37%, F21.52%
and assuming that carbon is 4 and O, C4,o, H3,O
A product corresponding to SI'Ji,o 1F1.12 was obtained.

Separately, the copper content was analyzed and found to be 4.0 carbon and 0.001 copper. This is C for pyrrole.
This indicates that u(BF4>2 has reacted, and in particular, the anion portion thereof has been added.

As a result of measuring the bulk density of this black powdery substance using a measuring cylinder, the result was 0.14 g/mu, indicating that it is a conductive material with a large bulk density.

In addition, put a certain amount of the black powder obtained by the above treatment into a 50 mN measuring cylinder, and apply vibration by hitting the bottom of the measuring cylinder until the volume of the powder converges to a certain value.The bulk density is determined from the volume and weight of the powder at that time. The above bulk density was measured by calculating.

Further, as a result of measuring the electric conductivity of this black material by the two-probe method, it was found to be 0.63 cm', indicating that it is an organic conductor with high conductivity.

The electrical conductivity was measured as follows.

First, the black powder obtained by the above treatment was ground sufficiently finely in a mortar, and then pressure-molded into a disk shape with a diameter of
ton/c12). Next, this disk sample was sandwiched between two copper cylinders of the same size, and a 1.2 kg load was applied from the top.
Apply a load of
6851), and the electrical conductivity of the disk sample was measured using this meter.

Comparative Example 1 An experiment was carried out in the same manner as in Example 1 except that LiBF4 was not used. As a result, 3.3 g of a black powdery substance was obtained.

When we conducted an elemental analysis of this black powdery substance, we found that
Assuming carbon is 4.0 8・C4,0−N3.5・No
, 9.Fl, 00 was obtained. Further, the bulk density of this black powdery substance was as small as 0.06 Mmg, which was about 1/2 of the amount of polymerization obtained in the treatment of Example 1 in the coexistence of salt. The electrical conductivity of this black object is 0.093 cm-1
Met.

From the above, it was confirmed that by coexisting a salt as described above, the bulk density of the resulting conductive material can be increased without deteriorating other physical properties.

Example 2゜Example 1 except that the amount of LiBF4 used was 1.88 g (0.02 mol) instead of 7.50 g (0.08 mol).
As a result of conducting an experiment in the same manner as above, a black powdery substance of 3.29 was obtained. Elemental analysis of this black powder substance revealed that, assuming that carbon is 4.0, C4.01
A product corresponding to H3,1, N1.01Fi, oa was obtained. Further, the bulk density of this black powder was 0.10 Mmg, and the electrical conductivity was 37) in o, i s cm'.

Example 3゜L i AS F615.67g instead of LiBF4
An experiment was conducted in the same manner as in Example 1 except that (0.08 mol) was used. As a result, 3.4 g of black powdery substance (
It's q. Elemental analysis of this black powdery substance revealed that, assuming that the carbon content was 4.0, it was C4,0/N3. O-N
The bulk density of this black powder was 0.13 MmN, and the electrical conductivity was 0.48 Cm-'.

Examples 4 to 13゜Results of manufacturing conductive materials in the same manner as in Example 1 using various pyrrole compounds and oxidizing agents formed by coexisting various cupric compounds, nitrile compounds, and salts. are shown in Table 1.

<Effects of the Invention> As described above, according to the manufacturing method of the present invention, the bulk density of the conductive material obtained is increased, and as a result, it is possible to facilitate its handling and manufacture, which is economically advantageous. This has the advantage that this type of conductive material can be manufactured.

Claims (1)

[Scope of Claims] 1. A method for producing a pyrrole polymer by reacting a pyrrole compound in the presence of an oxidizing agent containing a cupric compound and a nitrile compound, in which a salt is added during the reaction. A method for producing a conductive material characterized by coexisting with the following. 2. The cupric compound has the general formula CuX_m...(1) (wherein, X is ClO_4^-, BF_4^-, AsF_
6^-, PF_6^-, SbF_6^-, CH_3C_
6H_4SO_3^-, CF_3SO_3^-, ZrF
_6^-^-, TiF_6^-^- or SiF_6^
-^-, and m represents an integer of 1 to 2. ) The method according to claim 1, which is a cupric compound represented by: 3. The nitrile compound has the general formula R(CN)_n...(2) (wherein R represents an alkyl group, alkenyl group, or aryl group that may have a substituent, and n is 1 to 3 2. The method according to claim 1, wherein the nitrile compound is a nitrile compound represented by: 4. The above pyrrole compound has the general formula ▲ Numerical formula, chemical formula, table, etc. ▼... (3) (In the formula, R^1 and R^2 are hydrogen atoms, alkyl groups, alkoxy groups, aryl groups, allyloxy The method according to claim 1, wherein the pyrrole compound is a pyrrole compound represented by the following formula (representing an amino group, an alkylamino group, or an arylamino group). 5. The salt is an organic or inorganic salt or double salt that is soluble in the reaction system containing the oxidizing agent and easily ionically dissociated, and has the general formula MaX (4) (where M is an alkali metal or is a quaternary alkylammonium group, X is a perchlorate ion, a fluorine metal anion, or a sulfonic acid anion, and a represents an integer of 1 to 2. A method according to claim 1.