JPH0830108B2 - Method for manufacturing conductive material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to the production of a conductive material composed of a conjugated polymer obtained by using an oxidizing agent composed of a specific cupric compound and a nitrile compound. It is about the method.

<Prior Art> Polymers having a conjugated double bond in the main chain, such as polyacetylene, polyparaphenylene, polyphenylene, polypyrrole, polyparaphenylene vinylene, and polyaniline are arsenic pentafluoride, antimony pentafluoride, iodine, and bromine. ，
It has been conventionally known that treatment with a P-type or N-type doping agent such as sulfur trioxide, n-butyllithium, or sodium naphthalene significantly improves electric conductivity and changes from an insulator to a semiconductor or a conductor. There is. These conductive materials, so-called conductive polymers, are powdery, granular, lumpy,
It is obtained as a film and used as it is or after being molded depending on the application, and functions as an antistatic material, electromagnetic wave shielding material, photoelectric conversion element (electro-optical functional element), optical memory (holographic memory), various sensors, etc. Applications to a wide range of fields such as devices, display devices (electrochromism), switches, various hybrid materials (transparent conductive films, etc.), various terminal devices, etc. are being studied.

Of the above various conductive polymers, polythienylene,
Compared to polyacetylene, polypyrrole and polyaniline are one of the conductive polymers that have better stability in air, extremely less oxidative deterioration, and are easy to handle, and are being investigated for various applications that take advantage of these characteristics. Has been.

Known methods for producing polythienylene, polypyrrole, polyaniline, and the like include a method of electrochemically oxidative polymerization (electrolytic polymerization) and a method of chemically oxidative polymerization using an oxidizing agent. Then, in the method, polythienylene, polypyrrole, or polyaniline is deposited in a film form on the anode used for electrolytic polymerization, and the film-like polythienylene, polypyrrole, or polyaniline is obtained by peeling from the anode after the deposition.
In the other method, a peroxide such as potassium persulfate or ammonium persulfate, an acid such as nitric acid, sulfuric acid or chromic acid, an oxidizing agent such as a ferric chloride, ruthenium chloride, tungsten chloride or a Lewis acid such as molybdenum chloride is used. By using it, oxidative polymerization is carried out in a solid phase, a liquid phase or a gas phase to obtain a powdery polypyrrole. It has also been proposed to use ferric perchlorate as an oxidant in an organic solvent to perform oxidative polymerization to obtain a similar powdery polypyrrole (for example, Mol.Cryst.Liq.Cryst. Magazine, 1985. Year vol 118
Pp. 149-153).

<Problems to be Solved by the Invention> However, in the above method, polythienylene,
Since polypyrrole and polyaniline are produced in the form of a film on the anode as described above, the size of the product is restricted by the size of the electrode plate, which is greatly restricted in terms of mass productivity, and the electrolytic polymerization method is used. Therefore, there is a problem that the manufacturing method is complicated and the cost is high.

In the case of the other method, although there is no problem such as, since the electric conductivity of the obtained polythienylene, polypyrrole, polyaniline, etc. is small, there is a problem that the application range is narrowed due to restrictions on development to various applications. I have it.

Furthermore, in the method, when ferric perchlorate is used as an oxidant in an organic solvent, the solubility of ferric perchlorate in the organic solvent is much smaller than that in an aqueous solution, so that mass productivity is improved. However, there is a problem in that the electrical conductivity of the polypyrrole produced is very small because the concentration of the doping agent in the solvent is reduced by the amount of the decrease in the solubility. In addition, there is also a problem in that various safety measures must be taken in the manufacturing process because an organic solvent that has a high risk of explosion or the like is handled.

<Means for Solving Problems> The present inventor does not have the above-mentioned problems and is stable in the air, of course, has a large reaction rate, a large amount of production, and is easy to manufacture, and the electric As a result of research on a method for producing a conductive material having a high conductivity, the present invention has been completed by finding that the intended purpose can be achieved by using the following means.

That is, the present invention provides a method for producing a conductive material comprising a conjugated polymer obtained by reacting a conjugated compound with an oxidizing agent, wherein the oxidizing agent is a cupric compound and a general formula R (CN) _n. 2) (wherein R represents an alkyl group, an alkenyl group or an aryl group which may have a substituent, and n represents an integer of 1 to 3) in the coexistence of a nitrile compound. It exists in the manufacturing method of the electrically conductive material which makes it a point to use.

Examples of the cupric compound used in the present invention include, for example, the general formula CuX _m (1) (wherein, X is ClO ₄ ⁻ , BF ₄ ⁻ , AsF ₆ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , CH. ₃ C _{6
^{H 4 SO 3 -, CF 3}} SO 3 -, ZrF 6 -, TiF 6 - or SiF ₆ ^- represents, m represents an integer of 1-2. ) The cupric compound shown by these is mentioned.

In the production method of the present invention, a single or different two or more kinds of conjugated compounds are used, and this is composed of two or more cupric compounds, which are single or different, and two or more kinds of nitrile compounds, which are single or different. It can be reacted with an oxidant.

Examples of the conjugated compound used in the present invention include those represented by the general formula: (In the formula, R ¹ and R ² represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, an alkylamino group or an arylamino group, and X represents S or NR.
Represents ³ , and R ³ represents a hydrogen atom, an alkyl group or an aryl group. ) The thiophene type compound or pyrrole type compound shown by these are mentioned.

Furthermore, the general formula (In the formula, R ⁴ and R ⁵ represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, an alkylamino group, and an arylamino group, and R ⁶ and R ⁷ represent a hydrogen atom, an alkyl group, An aniline-based compound represented by the formula (1) represents an aryl group.

Further general formula Or (In the formula, R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , and R ¹² represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, an alkylamino group, or an arylamino group.). And a bithiophene-based compound or a terthiophene-based compound.

The cupric compound represented by the general formula (1) is specifically Cu (ClO ₄ ) ₂ , Cu (BF ₄ ) ₂ , Cu (PF ₆ ) ₂ , Cu (AsF
₆ ) ₂ , Cu (SbF ₆ ) ₂ , Cu (CH ₃ C ₆ H ₄ SO ₃ ) ₂ , Cu (CF ₃ SO ₃ )
₂ , CuZrF ₆ , CuTiF ₆ , and CuSiF ₆ , which are usually used as a compound having water of crystallization or an aqueous solution.

In the nitrile compound represented by the 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 sec-butyl group, a tert-butyl group, a vinyl group. ,, methyl vinyl group, dimethyl vinyl group, ethyl vinyl group, diethyl vinyl group,
n-propyl vinyl group, n-butyl vinyl group, phenyl vinyl group, naphthyl vinyl group, hydroxymethyl group, hydroxyethyl group, hydroxypropyl group, hydroxybutyl group, methoxymethyl group, methoxyethyl group, methoxypropyl group, ethoxymethyl group , Ethoxyethyl group, cyanomethyl group, cyanoethyl group, cyanopropyl group, cyanobutyl group, cyanopentyl group, cyanohexyl group, carboxymethyl group, carboxyethyl group, carboxypropyl group, phenyl group, naphthyl group, toluyl group, hydroxyphenyl group , Hydroxynaphthyl group, methoxyphenyl group, ethoxyphenyl group, methoxynaphthyl group, cyanophenyl group, dicyanophenyl group, cyanotoluyl group, dicyanotoluyl group, cyanonaphthyl group, carboxyphenyl group Group, a carboxymethyl tolyl group. As such a nitrile compound, specifically, acetonitrile, n-propionitrile, isopropionitrile, n-butyronitrile, isobutyronitrile, tert-butyronitrile, acrylonitrile, methylacrylonitrile, ethylacrylonitrile, phenylacrylonitrile, Acetone cyanohydrin, methylene cyanohydrin, ethylene cyanohydrin, propylene cyanohydrin, methoxyacetonitrile, ethoxyacetonitrile, methoxypropionitrile, malondinitrile, adiponitrile, cyanoacetic acid, cyanopropionic acid, cyanobutyric acid, benzonitrile, Naphthonitrile,
Examples include methylbenzonitrile, hydroxybenzonitrile, phthalonitrile, tricyanobenzene, methoxybenzonitrile, carboxybenzonitrile and the like.

In the thiophene compound or the pyrrole compound represented by the general formula (3), a thiophene compound or a pyrrole compound having no substituent at the 2,5 position of the five-membered ring skeleton structure is preferable. Further, specifically, R ¹ and R ² are each a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, or t.
ert-butyl group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, phenyl group, toluyl group, naphthyl group, phenoxy group, methylphenoxy group, naphthoxy group, amino group, dimethylamino group , Diethylamino group, phenylamino group, diphenylamino group, methylphenylamino group, phenylnaphthylamino group, X represents S or NR ³ , R ³ represents a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, It represents an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a phenyl group, a toluyl group and a naphthyl group.

As such a thiophene-based compound or a pyrrole-based compound, specifically, thiophene-based compounds such as thiophene, 3-methylthiophene, 3-ethylthiophene,
3-n-propylthiophene, 3-isopropylthiophene, 3-n-butylthiophene, 3-isobutylthiophene, 3-sec-butylthiophene, 3-tert-butylthiophene, 3-methoxythiophene, 3-ethoxythiophene, 3- n-propoxythiophene, 3-n-
Butoxythiophene, 3-phenylthiophene, 3-toluylthiophene, 3-naphthylthiophene, 3-phenoxythiophene, 3-methylphenoxythiophene,
3-naphthoxythiophene, 3-aminothiophene, 3
-Dimethylaminothiophene, 3-diethylaminothiophene, 3-diphenylaminothiophene, 3-methylphenylaminothiophene, 3-phenylnaphthylthiophene and the like.

Further, as the pyrrole compound, 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 -Iso-propylpyrrole, 3-n-butylpyrrole, 3-methoxypyrrole, 3-ethoxypyrrole, 3-n-propoxypyrrole, 3-n-butoxypyrrole, 3-phenylpyrrole, 3-toluylpyrrole, 3-naphthyl Pyrrole, 3-phenoxypyrrole, 3-methylphenoxypyrrole, 3-naphthoxythiophene, 3-aminopyrrole, 3-dimethylaminopyrrole, 3-diethylaminopyrrole, 3-diphenylaminopyrrole, 3-methylphenylaminopyrrole, 3- Such as phenylnaphthylaminopyrrole That.

In the aniline-based compound represented by the general formula (4), R ⁴ and R ⁵ are hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, methoxy group, ethoxy group, n-propoxy group, n-butoxy group, phenyl group, toluyl group, naphthyl group, phenoxy group, methylphenoxy group, naphthoxy group, amino group, dimethylamino group, diethylamino group, Represents a phenylamino group, a diphenylamino group, a methylphenylamino group, a phenylnaphthylamino group, and R ⁶ and R ⁷ are hydrogen atoms, methyl groups, ethyl groups, n-propyl groups, isopropyl groups, n-butyl groups, phenyl groups. , Toluyl group and naphthyl group.

Specific examples of such aniline compounds include aniline, methylaniline, ethylaniline, n-propylaniline, isopropylaniline, n-butylaniline,
Methoxyaniline, ethoxyaniline, n-propoxyaniline, phenylaniline, toluylaniline, naphthylaniline, phenoxyaniline, methylphenoxyaniline, naphthoxyaniline, aminoaniline, dimethylaminoaniline, diethylaminoaniline, phenylaminoaniline, diphenylaminoaniline, methyl Examples include phenylaminoaniline and phenylnaphthylaminoaniline.

In the bithiophene-based compound and terthiophene-based compound represented by the general formula (5) or (6), R ⁸ , R ⁹ ,
R ¹⁰ , R ¹¹ and R ¹² are hydrogen atom, methyl group, ethyl group, n-
Propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, methoxy group,
Ethoxy group, n-propoxy group, n-butoxy group, phenyl group, toluyl group, naphthyl group, phenoxy group, methylphenoxy group, naphthoxy group, amino group, dimethylamino group, diethylamino group, diphenylamino group, methylphenylamino group Represents a phenylnaphthylamino group.

Specific examples of such compounds include 2,2'-bithiophene, 3-methyl-2,2'-bithiophene, 3-ethyl-2,2'-bithiophene, 4-n-propyl-2,2 '.
-Bithiophene, 3-methyl-3'-methyl-2,2'-
Bithiophene, 3-methoxy-2,2'-bithiophene,
3-ethoxy-2,2'-bithiophene, 3-phenyl-
2,2'-bithiophene, 3-phenoxy-2,2'-bithiophene, 3-amino-2,2'-bithiophene, 3-dimethylamino-2,2'-bithiophene, 3-diethylamino-2,2'- Bithiophene, 2,2 ', 5', 2 "-terthiophene, 3-methyl-2,2 ', 5', 2" -terthiophene,
Examples thereof include 3-methyl-3'-methyl-2,2 ', 5', 2 "-terthiophene.

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

Further, the nitrile compound represented by the general formula (2) is used in coexistence with the cupric compound, and examples of its usage include the following methods.

1) A nitrile compound and a cupric compound are allowed to coexist in advance and then allowed to act on a conjugated compound.

2) The cupric compound is allowed to act on the system in which the conjugated compound and the nitrile compound coexist.

3) The nitrile compound is allowed to act on the system in which the conjugated compound and the cupric compound coexist.

4) The system in which the cupric compound and the nitrile compound coexist is allowed to act on the system in which the conjugated compound and the nitrile compound coexist.

5) The reaction product of the cupric compound and the nitrile compound is isolated in advance and allowed to act on the conjugated compound.

Due to the coexistence of such a nitrile compound, the reaction between the conjugated compound and the oxidizing agent is significantly accelerated, and even in a system in which substantially no oxidative polymerization reaction proceeds, the oxidative polymerization reaction may easily proceed. Was found.

The use of the nitrile compound represented by the general formula (2) is 0.01 to 10,000 times mol per 1 mol of the cupric compound,
It is preferably 0.1 to 1,000 times mol.

When the nitrile compound is a liquid substance, it is used as a reaction solvent, and when it is a solid substance, any solvent, for example, water, alcohol solvents such as methanol, ethanol, tetrahydrofuran, dioxane, benzene, toluene. Ordinary organic solvents such as dichloromethane, dichloroethane, and acetic acid can be used.

The reaction temperature is −50 ° C. to 150 ° C., preferably −20 ° C.
~ 100 ° C. Reaction time is related to reaction temperature but usually
It is 0.5 to 200 hours, preferably 1.0 to 100 hours.

The reaction of the cupric compound represented by the general formula (1) with, for example, the thiophene-based compound or the pyrrole-based compound represented by the general formula (3) is performed in any phase of a solid phase, a liquid phase and a gas phase. It can be carried out, but it is preferred to react in the liquid phase.

The reaction product is a dark brown to black powdered substance, and in the reaction in the presence of the solvent, after the reaction is completed, the solvent is removed by usual information, and then in the present invention, a liquid nitrile compound, for example, acetonitrile. It is preferable to wash and purify the reaction product several times with a solvent such as propionitrile and to dissolve and remove the by-produced cuprous compound so that a product having higher conductivity can be obtained.

<Operation> By using the above method, it is possible to obtain a conductive material which does not have the above-mentioned conventional problems, has a large reaction and generation rate, is easy to manufacture, and has a large electric conductivity.

<Examples> Examples of the manufacturing method of the present invention will be specifically described below with reference to Examples.

Example 1 Pyrrole (8.0 g, 0.12 mol) and acetonitrile (450 ml) were placed in a round-bottomed flask of Example 1, and the solution was stirred at room temperature (15 to 20 ° C.) in a nitrogen atmosphere and 45% prepared in advance.
Cu (BF ₄ ) ₂ aqueous solution 189.7g (0.36mol) and acetonitrile
The mixture with 150 ml was added dropwise over 15 minutes.

Exothermic heat was recognized upon dropping, and the reaction liquid immediately turned black, and powdery solid matter was deposited in the reaction liquid to give a slurry form. After stirring for 2 hours, the mixture was left at room temperature overnight.
When the reaction product was separated, a black powdery substance containing a white crystalline substance was obtained. 4 of this with 600 ml of acetonitrile
After repeated washing, the white crystalline substance was removed and the temperature
After drying under reduced pressure at 60 ° C., 12.4 g of a black powdery substance was obtained.

An elemental analysis of a black material revealed that C45.28%, H2.63%, N1
2.48%, F24.12%, assuming carbon of 4.0
The equivalents of C _4.0 , H _2.8 , N _0.95 , F _0.33 were obtained. In addition, as a result of separately analyzing the content of copper, it was confirmed that
It was 0.001. This indicates that Cu (BF ₄ ) ₂ was reacted with pyrrole, and in particular, its anion portion was added.

As a result of measuring the electric conductivity of this black material by the two-terminal method, 1.2 × 10 ^-1 Scm ^-1 was obtained, which was found to be an organic semiconductor having conductivity in the semiconductor region.

The measurement of the electric conductivity was performed as follows. First, the black powder obtained by the above treatment was crushed into fine particles in a mortar, and then pressed into a disk with a diameter of 10 mm (5 ton / cm).
² ) I did. Then, this disk sample was
It is sandwiched between two copper cylinders, 1.2 kg is applied from the top,
The lead wires were taken out from the upper and lower copper cylinders and connected to a digital multimeter (Takedauriken TR6851), and the electric conductivity of the disk sample was measured by this meter.

For comparison, the polymerization reaction of pyrrole was carried out in the same manner as in Example 1 except that acetonitrile was not used at all. As a result, the reaction substantially did not proceed and the reaction product was extremely small.

From the above results, it was confirmed that by using acetonitrile, the reaction of polypyrrole and the cupric compound proceeded rapidly and a large amount of reaction product was obtained.

Example 2 The experiment was conducted in the same manner as in Example 1 except that 9.7 g of N-methylpyrrole was used instead of pyrrole, and the result was 12.6.
g of a black powdery substance was obtained. From the elemental analysis of the obtained black substance, assuming that carbon is 5.0, C _5.0 , H _5.1 , N _1.0 , F
We got the equivalent of _0.28 .

This indicates that Cu (BF ₄ ) ₂ was reacted with N-methylpyrrole, and in particular, its anion portion was added. The electrical conductivity of this black material is 4.
It was 2 × 10 ^-3 Scm ^-1 .

Examples 3 to 29 Various conjugated compounds were used, and the reaction between these and various cupric compounds was carried out in the same manner as in Example 1. The examination results of the obtained dark brown to black powder are shown in Table 1. When the reaction was carried out using a solvent other than the nitrile compound, the solvent used is shown in Table 1.

<Effects of the Invention> As described above, according to the production method of the present invention, it is possible to obtain an organic semiconductor which can increase the reaction and production rates, is easy to produce, has a large electric conductivity, and is also excellent in oxidation resistance. Many kinds are obtained, and their practical value is extremely large.

Claims (6)

[Claims] 1. A method for producing a conductive material comprising a conjugated polymer obtained by reacting a conjugated compound with an oxidizing agent, wherein a cupric compound as the oxidizing agent and a general formula R (CN) _n. 2) (wherein R represents an alkyl group, an alkenyl group or an aryl group which may have a substituent, and n represents an integer of 1 to 3) in the coexistence of a nitrile compound. A method for producing a conductive material, which is characterized by using the same. Wherein said cupric compound is the general formula CuX _m ...... (1) (wherein, X is ^{_{ClO 4 -, BF 4 -,}} AsF 6 -, PF 6 -, SbF 6 -, CH 3 C _{6
^{H 4 SO 3 -, CF 3}} SO 3 -, ZrF 6 -, TiF 6 - or SiF ₆ ^- represents, m represents an integer of 1-2. ) A cupric compound represented by the following: The method for producing a conductive material according to claim 1, wherein 3. The conjugated compound has the general formula (In the formula, R ¹ and R ² represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, an alkylamino group or an arylamino group, and X represents S or NR ³
And R ³ represents a hydrogen atom, an alkyl group or an aryl group. ) A thiophene-based compound or a pyrrole-based compound represented by the formula (3). 4. The conjugated compound has the general formula (In the formula, R ⁴ and R ⁵ represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, an alkylamino group, and an arylamino group, and R ⁶ and R ⁷ represent a hydrogen atom, an alkyl group, The method for producing a conductive material according to claim 1, wherein the conductive material is an aniline compound represented by: 5. The conjugated compound has the general formula Or (In the formula, R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , and R ¹² represent a hydrogen atom, an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, an alkylamino group, or an arylamino group.). The method for producing a conductive material according to claim 1, which is a bithiophene-based compound or a terthiophene-based compound. 6. The method for producing a conductive material according to claim 1, wherein the reaction product of the conjugated compound and the oxidizing agent is purified with a liquid nitrile compound.