JP2013018954A - Conductive polymer precursor and conductive polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive polymer precursor suitable as a precursor of a conductive polymer having high conductivity, and to provide a conductive polymer obtained by polymerizing the conductive polymer precursor.SOLUTION: The conductive polymer precursor is expressed by general formula (1), and the conductive polymer is obtained by polymerizing the conductive polymer precursor. In the formula, Rrepresents a hydrogen atom or a straight-chain or branched alkyl group, in which the nitrogen atom bonded to Rcan form a secondary or tertiary amino group or its salt; Rto Rare each independently selected from specific substituents; and in Rto R, at least one is a hydrogen atom, at least one is an electron-donating group, at least one is an amino group or its salt, and at least one is an acidic group or its salt.

Description

  The present invention relates to a conductive polymer precursor suitable as a conductive polymer precursor, and a conductive polymer obtained by polymerizing the conductive polymer precursor.

As a conductive polymer used in various applications, a polyaniline-based conductive polymer is known.
In general, the conductivity (σ) of a conductive polymer depends on the charge (q) of the carrier, the number of carriers (n), and the mobility (μ) between and within the molecular chains of the carrier, It is derived from the following formula (I).
σ = qnμ (I)

In the case of a polyaniline-based conductive polymer, the carrier charge (q) is an eigenvalue determined by the type of carrier. Therefore, in order to improve conductivity, the number of carriers (n) and mobility (μ) must be It is important to increase.
Increasing the molecular weight of the polymer is considered effective for increasing the mobility (μ).
On the other hand, in order to increase the number (n) of carriers, it is considered effective to introduce an acidic group such as a sulfonic acid group and remove a base that inhibits dope.

As a polyaniline-based conductive polymer into which an acidic group is introduced, a copolymer of a self-doped aniline having an acidic group and a non-self-doped aniline has been proposed.
For example, in Non-Patent Document 1, p-aminodiphenylamine and o-aminobenzenesulfonic acid are used as a conductive polymer precursor (conductive polymer precursor), and these are copolymerized at an arbitrary polymerization ratio. A polymer is disclosed.
Non-Patent Document 2 discloses a conductive polymer obtained by polymerizing a compound (18): 4-aminodiphenylamine-2-sulfonic acid shown below as a conductive polymer precursor.

Polymer Journal 2001, 33 (2), 165-171. Synthetic Metals 2001, 123, 273-277

However, the conductive polymers described in Non-Patent Documents 1 and 2 did not sufficiently satisfy the conductivity.
In particular, in Non-Patent Document 1, since the polymerization ratio is controlled by a combination of specific conductive polymer precursors, the versatility of usable conductive polymer precursors is lacking.

  The present invention has been made in view of the above circumstances, and includes a conductive polymer precursor suitable as a conductive polymer precursor having high conductivity, and a conductive polymer obtained by polymerizing the conductive polymer precursor. The purpose is to provide.

  As a result of intensive studies, the inventors of the present invention can improve conductivity while increasing the number of carriers (n) by using a linear conductive polymer as shown in the following general formula (3), for example. I found out that I can do it.

Such a linear conductive polymer tends to be more easily obtained by polymerizing a dimer such as the compound (18) as a starting material than polymerizing the monomer as a starting material.
However, as described above, the conductive polymer obtained by polymerizing the compound (18) did not sufficiently satisfy the conductivity. In the case of the compound (18), this may be caused by the fact that the polymerization reactivity of aniline is low and it is difficult to form a linear conductive polymer when polymerized.
Therefore, as a result of further studies, the present inventors have been able to improve the polymerization reactivity of aniline by introducing one or more electron donating groups into the dimer in order to obtain a linear conductive polymer. The present invention has been completed based on the idea that it should be.

  That is, the conductive polymer precursor of the present invention is represented by the following general formula (1).

In formula (1), R ¹ is a hydrogen atom or a linear or branched alkyl group, wherein the nitrogen atom to which R ¹ is bonded forms a secondary or tertiary amino group or a salt thereof. R ^{2 to} R ¹¹ are each independently a hydrogen atom, an electron donating group, a hydroxyl group, a nitro group, a halogen atom, a cyano group, an alkylcarbonyloxy group, an amino group or a salt thereof, and an acidic group or a salt thereof. At least one of R ^{2 to} R ¹¹ is a hydrogen atom, at least one is an electron donating group, at least one is an amino group or a salt thereof, and at least one of R ^{2 to} R ¹¹ is selected from the group consisting of Is an acidic group or a salt thereof.

  In particular, it is preferably represented by the following general formula (2).

In formula (2), R ^{12 to} R ¹⁹ are each independently a group consisting of a hydrogen atom, an electron donating group, a hydroxyl group, a nitro group, a halogen atom, a cyano group, an alkylcarbonyloxy group and an acidic group or a salt thereof. And at least one of R ^{12 to} R ¹⁹ is an electron donating group, at least one is an acidic group or a salt thereof, and R ²⁰ is an amino group or a salt thereof.

  The conductive polymer of the present invention is obtained by polymerizing the conductive polymer precursor.

The conductive polymer precursor of the present invention is suitable as a precursor of a conductive polymer having high conductivity.
Moreover, the conductive polymer of this invention has high electroconductivity.

1 is a ¹ H-NMR spectrum of a compound (1-2) obtained in Example 1.

Hereinafter, the present invention will be described in detail.
[Conductive polymer precursor]
The conductive polymer precursor of the present invention is a compound represented by the following general formula (1) (hereinafter referred to as “compound (1)”).
In the present invention, “conductivity” means having a volume resistivity of 10 ⁹ Ω · cm or less.

In formula (1), R ¹ is a hydrogen atom or a linear or branched alkyl group.
As the alkyl group, a linear or branched alkyl group having 1 to 8 carbon atoms is preferable. For example, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, a t-butyl group. A butyl group etc. are mentioned.
R ¹ is preferably a hydrogen atom from the viewpoint of easily obtaining a highly linear polymer.

Further, the nitrogen atom to which R ¹ is bonded may form a secondary or tertiary amino group or a salt thereof.
When the nitrogen atom to which R ¹ is bonded forms a secondary or tertiary amino group salt, examples of the amino group salt include organic acid salts and inorganic acid salts of secondary or tertiary amino groups. Specifically, secondary or tertiary amino group hydrochloride, sulfate, phosphate, carbonate, borofluoride, formate, acetate, propionate, methanesulfonate, toluenesulfonic acid Salt, trifluoromethanesulfonate, camphorsulfonate, dodecylbenzenesulfonate, and the like.

In formula (1), R ^{2 to} R ¹¹ are each independently a hydrogen atom, an electron donating group, a hydroxyl group, a nitro group, a halogen atom, a cyano group, an alkylcarbonyloxy group, an amino group or a salt thereof, and an acidic group. Or it is chosen from the group which consists of the salt.

Examples of the electron donating group include an alkoxy group and an alkyl group.
As the alkoxy group, an alkoxy group having a linear or branched alkyl group having 1 to 8 carbon atoms is preferable. For example, a methoxy group, an ethoxy group, an n-propoxy group, an iso-propoxy group, an n-butoxy group, or a sec-butoxy group. Group, t-butoxy group and the like are exemplified, but the group is not particularly limited.
As the alkyl group, a linear or branched alkyl group having 1 to 8 carbon atoms is preferable. For example, a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a sec-butyl group, a t-butyl group. Although a butyl group etc. are mentioned, it is not specifically limited.
As the electron donating group, an alkoxy group is preferable from the viewpoint of higher polymerizability.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the alkylcarbonyloxy group include a methylcarbonyloxy group, an ethylcarbonyloxy group, an n-propylcarbonyloxy group, an iso-propylcarbonyloxy group, and an n-butylcarbonyloxy group.

Examples of the amino group include a primary amino group.
Examples of the amino group salts include organic acid salts and inorganic acid salts of primary amino groups. Specifically, primary amino group hydrochloride, sulfate, phosphate, carbonate, borofluoride, formate, acetate, propionate, methanesulfonate, toluenesulfonate, trifluoro Examples include lomethane sulfonate, camphor sulfonate, and dodecylbenzene sulfonate.

Examples of the acidic group include a sulfonic acid group, a carboxyl group, and a phosphoric acid group. Among these, a sulfonic acid group is preferable from the viewpoint that the affinity for water can be increased, and when a conductive polymer is obtained, higher conductivity can be exhibited.
Examples of the acid group salt include an alkali metal salt, an alkaline earth metal salt, an ammonium salt, and a substituted ammonium salt.

Examples of the alkali metal include lithium, sodium, and potassium.
Examples of the alkaline earth metal include magnesium and calcium.
Examples of substituted ammonium include alicyclic ammoniums, cyclic saturated ammoniums, and cyclic unsaturated ammoniums.
Examples of the fatty ammoniums include ammonium represented by the following general formula (4).

In Formula (4), R ^{21 to} R ²⁴ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
Specific examples of such fatty ammoniums include methylammonium, dimethylammonium, trimethylammonium, ethylammonium, diethylammonium, triethylammonium, methylethylammonium, diethylmethylammonium, dimethylethylammonium, propylammonium, dipropylammonium, Isopropylammonium, diisopropylammonium, butylammonium, dibutylammonium, methylpropylammonium, ethylpropylammonium, methylisopropylammonium, ethylisopropylammonium, methylbutylammonium, ethylbutylammonium, tetramethylammonium, tetramethylolammonium, tetraethylammonium, tetran- Chill ammonium, tetra sec- butyl ammonium, and the like can be exemplified tetra t- butyl ammonium. Among these, from the viewpoint of solubility, it is most preferable that one of R ^{21 to} R ²⁴ is a hydrogen atom and the other three are alkyl groups having 1 to 4 carbon atoms, and then two of R ^{21 to} R ²⁴ are hydrogen. The case where the atom and the other two are alkyl groups having 1 to 4 carbon atoms is preferred.

Examples of the cyclic saturated ammoniums include piperidinium, pyrrolidinium, morpholinium, piperazinium, and derivatives having these skeletons.
Examples of the cyclic unsaturated ammonium include pyridinium, α-picolinium, β-picolinium, γ-picolinium, quinolinium, isoquinolinium, pyrrolinium, and derivatives having these skeletons.

In the compound (1), at least one of R ^{2 to} R ¹¹ is a hydrogen atom, at least one is an electron donating group, at least one is an amino group or a salt thereof, and at least one is An acidic group or a salt thereof.
From the viewpoint of excellent polymerizability and improved conductivity when it becomes a conductive polymer, it is preferable that either one of R ⁴ and R ⁹ is a hydrogen atom and the other is an amino group or a salt thereof.

Further, the remaining substituents (R ² , R ³ , R ^{5 to} R ⁸ , R ¹⁰ , R ¹¹ ) are preferably hydrogen atoms, substituents other than amino groups or salts thereof. In particular, it is preferable that at least one of R ^{2 to} R ⁶ is an electron donating group, and at least one of R ^{7 to} R ¹¹ is an electron donating group.
Furthermore, as long as at least one of R ^{2 to} R ¹¹ is an acidic group or a salt thereof, the position and number thereof are not particularly limited, and for example, one each for R ^{2 to} R ⁶ and R ^{7 to} R ^11. it may be a ^more, R 2 to R ⁶ and may be one or more one or the other to the ^R 7 ^{to R 11.} In particular, from the viewpoint of excellent polymerizability and improved conductivity when it becomes a conductive polymer, one each for R ^{2 to} R ⁶ and R ^{7 to} R ¹¹ , or R ^{2 to} R ⁶ and R, respectively. ^{One to 7 to} R ¹¹ is preferable, and one of R ^{2 to} R ⁶ and R ^{7 to} R ¹¹ is more preferable from the viewpoint of further improving the conductivity. That is, it is more preferable that one of R ^{2 to} R ¹¹ is an acidic group or a salt thereof.
In addition, R < ² > -R < ⁶ >, R < ⁷ > -R < ⁹ > except an amino group or its salt, and an acidic group or its salt may couple | bond together, and may form an alicyclic ring or an aromatic ring.

  Among the compounds (1), a compound represented by the following general formula (2) (hereinafter referred to as “compound (2)”) is particularly preferable.

In formula (2), R ^{12 to} R ¹⁹ are each independently a group consisting of a hydrogen atom, an electron donating group, a hydroxyl group, a nitro group, a halogen atom, a cyano group, an alkylcarbonyloxy group and an acidic group or a salt thereof. R ²⁰ is an amino group or a salt thereof.
The electron donating group, halogen atom, alkylcarbonyloxy group, and acidic group are the electron donating group, halogen atom, alkylcarbonyloxy group, and acidic group exemplified above in the description of the compound (1).
In the compound (2), at least one of R ^{12 to} R ¹⁹ is an electron donating group, and at least one is an acidic group or a salt thereof.

Moreover, it is preferable that R < ¹² > -R < ¹⁹ > is substituents other than a hydrogen atom. In particular, it is preferable that at least one of R ^{12 to} R ¹⁵ is an electron donating group, and at least one of R ^{16 to} R ¹⁹ is an electron donating group.
^Further, among R 12 ^{to R 19,} if at least one acidic group or a salt thereof is not particularly limited as to its position and number, for example, ^R 12 ^{to R 15} and each of the one or more ^R 16 ^{to R 19} Alternatively, one or more of R ^{12 to} R ¹⁵ and R ^{16 to} R ¹⁹ may be used. In particular, from the viewpoint of excellent polymerizability and improved conductivity when it becomes a conductive polymer, one each of R ^{12 to} R ¹⁵ and R ^{16 to} R ¹⁹ , or R ^{12 to} R ¹⁵ and R ^{One from 16 to} R ¹⁹ is preferred, and one from R ^{12 to} R ¹⁵ and R ^{16 to} R ¹⁹ is more preferred from the viewpoint of further improving the conductivity. That is, it is more preferable that one of R ^{12 to} R ¹⁹ is an acidic group or a salt thereof.
In addition, R < ¹² > -R < ¹⁵ >, R < ¹⁶ > -R < ¹⁹ > except an amino group or its salt, and an acidic group or its salt may couple | bond together, and may form an alicyclic ring or an aromatic ring.

<Method for Producing Compound (1)>
Compound (1) is produced, for example, through the following steps (a) to (e). However, in the method shown below, in general formula (1), R ¹ is a hydrogen atom, and R ^{2 to} R ¹¹ are each independently a hydrogen atom, an electron donating group, a hydroxyl group, a cyano group, an alkylcarbonyloxy group. , An amino group or a salt thereof and an acid group or a salt thereof, wherein one of R ^{2 to} R ⁶ is an amino group and one of R ^{7 to} R ¹¹ is an acidic group (hereinafter, “ Compound (1-1) ").
In the reaction formulas shown below, X is a halogen atom, P is a protective group, and R ^{25 to} R ³² are each composed of a hydrogen atom, an electron donating group, a hydroxyl group, a cyano group, and an alkylcarbonyloxy group. Selected from the group, at least one of R ^{25 to} R ³² is a hydrogen atom, and at least one is an electron donating group.

(A) Process:
Step (a) is a protection step in which the amino group in compound (5) is protected with a protecting group (P) to obtain compound (6).

As the protecting group (P), a general protecting group for an amino group can be used. Specific examples include t-butoxycarbonyl group, benzyloxycarbonyl group, 9-fluorenylmethyloxycarbonyl group, 2,2,2-trichloroethoxycarbonyl group, allyloxycarbonyl group and the like.
In addition, as a reagent used in the protection step, a general reagent for an amino group can be used, and the acid anhydride and acid chloride are not particularly limited.
The reaction conditions in the protection step are not particularly limited as long as they are general reaction conditions for amino groups.

(B) Process:
Step (b) is a reduction step in which compound (6) is reduced to obtain compound (7).

  The reaction conditions in the reduction step are not particularly limited as long as they are general reduction conditions for nitro groups. Specifically, use of a reducing agent such as zinc powder or tin, catalytic hydrogenation in the presence of a catalyst such as platinum, palladium, nickel, etc. under acidic conditions. However, depending on the type of the protecting group in which the amino group is protected in the step (a), attention should be paid to the reducing agent used and the reaction conditions.

(C) Process:
Step (c) is a coupling step in which compound (7) and compound (8) are coupled to obtain compound (9).

  The reaction in the coupling step is not particularly limited as long as it is a general coupling reaction for synthesizing secondary or tertiary amines. Specifically, a Buchward-Hartwig cross-coupling reaction using a palladium catalyst is exemplified.

(D) Process:
Step (d) is a deprotection step in which compound (10) is obtained by deprotecting the protecting group (P) of the amino group in compound (9).

  For the reaction in the deprotection step, a general deprotection reaction can be used, and the conditions may be selected according to the protective group (P).

(E) Process:
The step (e) is a sulfonation step for sulfonating the compound (10) to obtain the compound (1-1).

The reagent used in the sulfonation step can be used without particular limitation as long as it is a reagent generally used in sulfonation of aromatic rings. Specific examples include sulfuric acid and fuming sulfuric acid.
The sulfonation reaction condition is not particularly limited as long as it is a general reaction condition for an aromatic ring.

<Other embodiments>
Compound (1-1) can also be produced, for example, through the following steps (f) to (i).

(F) Process:
Step (f) is a coupling step in which compound (11) and compound (12) are coupled to obtain compound (13).

  The reaction in the coupling step is not particularly limited as long as it is a general coupling reaction for synthesizing secondary or tertiary amines. Specifically, a Buchward-Hartwig cross-coupling reaction using a palladium catalyst is exemplified.

(G) Process:
Step (g) is a reduction step in which compound (13) is reduced to obtain compound (10).

  The reaction conditions in the reduction step are not particularly limited as long as they are general reduction conditions for nitro groups. Specifically, use of a reducing agent such as zinc powder or tin, catalytic hydrogenation in the presence of a catalyst such as platinum, palladium, nickel, etc. under acidic conditions.

(H) Process:
Step (h) is a sulfonation step in which compound (10) is sulfonated to obtain compound (1-1).

The reagent used in the sulfonation step can be used without particular limitation as long as it is a reagent generally used in sulfonation of aromatic rings. Specific examples include sulfuric acid and fuming sulfuric acid.
The sulfonation reaction condition is not particularly limited as long as it is a general reaction condition for an aromatic ring.

In the compound (1-1), when at least one of R ^{25 to} R ²⁸ is an electron donating group, the compound (11 ′) obtained by the step (i) shown below is used as the step (f). May be provided. This method is particularly effective in the case of producing a compound in which an alkoxy group is present at the ortho-position and para-position, or at either position relative to the nitro group.
In the step (i), -OR ^{25 '} is an alkoxy group, X' is a halogen atom excluding a fluorine atom, and M is an alkali metal.

(I) Process:
Step (i) is a step of obtaining compound (11 ′) by substituting fluorine in compound (14) with an alkoxy group.

The substitution reaction is performed in the presence of an alkali metal alkoxide (R ^{25 ′} OM). Examples of the alkali metal alkoxide include sodium methoxide, sodium ethoxide, sodium isopropoxide, sodium butoxide, sodium tert-butoxide, potassium methoxide, potassium ethoxide, potassium isopropoxide, potassium butoxide, potassium tert-butoxide. Etc.
Since a known method can be employed for the substitution reaction, the conditions are not particularly limited. For example, the reaction solvent is preferably an alcohol solvent such as methanol, ethanol, or propanol. Moreover, it is preferable that reaction temperature is -10 degreeC-50 degreeC.

<Effect>
The conductive polymer precursor of the present invention described above has one or more amino groups or a salt thereof and one or more acidic groups or a salt thereof in addition to one or more electron donating groups in the molecule. . That is, since the aromatic ring substituted by the electron donating group becomes electron rich, the polymerization reactivity of aniline is improved. Further, it is effective in compensating for the electron shortage of the aromatic ring bonded to the electron-withdrawing group including an acidic group. In particular, among the electron donating groups, the alkoxy group has a strong electron donating property, so that the aromatic ring substituted with the alkoxy group is likely to be in an electron-rich state, and the polymerization reactivity of aniline becomes better. Furthermore, if the two aromatic rings are each substituted by an electron donating group (particularly an alkoxy group), the polymerization reactivity of aniline is particularly good.

Therefore, it is considered that when the conductive polymer precursor of the present invention is polymerized, a linear conductive polymer is obtained and high conductivity is expressed. In particular, if it is a conductive polymer precursor having one acidic group or a salt thereof in the molecule (that is, in the general formula (1), one of R ^{2 to} R ¹¹ may be an acidic group or a salt thereof). As will be described in detail later, a conductive polymer is obtained which is linear and has an acidic group introduced every other aniline unit. The conductive polymer has higher conductivity. It is thought to express sex.
Therefore, the conductive polymer precursor of the present invention is suitable as a precursor (raw material) for a conductive polymer having high conductivity.

[Conductive polymer]
The conductive polymer of the present invention is obtained by polymerizing the conductive polymer precursor of the present invention.
The method for producing the conductive polymer of the present invention is not particularly limited, and various synthetic methods such as chemical polymerization and electrolytic polymerization can be applied.
Hereinafter, an example of a method for producing the conductive polymer of the present invention by chemical polymerization will be specifically described.

The conductive polymer of the present invention can be obtained, for example, by polymerizing the conductive polymer precursor of the present invention with an oxidizing agent in the presence of a basic compound.
In addition, a conductive polymer precursor may be used individually by 1 type, and 2 or more types different in the range applicable to General formula (1) may be mixed and used in arbitrary ratios.

<Basic compound>
As the basic compound, ammonia, fatty amines, cyclic saturated amines, cyclic unsaturated amines, inorganic bases and the like are used. In particular, aliphatic amines, cyclic saturated amines, and cyclic unsaturated amines are preferred because of their availability.

  Examples of the fatty amines include compounds represented by the following general formula (15), ammonium hydroxide compounds represented by the following general formula (16), and the like.

In formula (15), R ^{33 to} R ³⁵ are each independently an alkyl group having 1 to 4 carbon atoms.

In formula (16), R ^{36 to} R ³⁹ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

As the cyclic saturated amines, piperidine, pyrrolidine, morpholine, piperazine and derivatives having these skeletons, and ammonium hydroxide compounds thereof are preferably used from the viewpoint of solubility.
Cyclic unsaturated amines include pyridine, α-picoline, β-picoline, γ-picoline, quinoline, isoquinoline, pyrroline, derivatives having these skeletons, and ammonium hydroxide compounds thereof from the viewpoint of solubility. Are preferably used.
Examples of inorganic bases include hydroxide salts such as sodium hydroxide, potassium hydroxide, and lithium hydroxide.

Among these basic compounds, methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylmethylamine, ethyldimethylamine, diethylmethylamine, pyridine, α-picoline, β-picoline, γ-picoline and the like are particularly preferable. Used. When these basic compounds are used, a highly conductive and highly pure conductive polymer can be obtained.
These basic compounds may be used individually by 1 type, and 2 or more types may be mixed and used for them in arbitrary ratios.

  The concentration of the basic compound is preferably 0.1 mol / L or more, more preferably 0.1 to 10.0 mol / L, and particularly preferably 0.2 to 8.0 mol / L. When the concentration of the basic compound is 0.1 mol / L or more, the conductive polymer can be obtained in high yield. On the other hand, if the concentration of the basic compound is 10.0 mol / L or less, the conductivity of the obtained conductive polymer tends to be improved.

  The molar ratio of the conductive polymer precursor to the basic compound is preferably conductive polymer precursor: basic compound = 1: 0.5 to 1: 2, more preferably 1: 0.75 to 1: 1.2. Here, when the ratio of a basic compound is low, the solubility with respect to a solvent will become low, the reactivity may fall, and the electroconductivity of the conductive polymer obtained may fall. On the other hand, when the proportion of the basic compound is high, the proportion of the acidic group and the basic compound in the resulting conductive polymer forming a salt may increase, and the conductivity of the conductive polymer may be reduced.

<Oxidizing agent>
The oxidizing agent is not particularly limited as long as the standard electrode potential is 0.6 V or more. For example, peroxodisulfuric acids such as peroxodisulfuric acid, ammonium peroxodisulfate, sodium peroxodisulfate, and potassium peroxodisulfate; It is preferable to use hydrogen peroxide or the like.
These oxidizing agents may be used individually by 1 type, and 2 or more types may be mixed and used for them in arbitrary ratios.

1-5 mol is preferable with respect to 1 mol of conductive polymer precursors, and, as for the usage-amount of an oxidizing agent, More preferably, it is 1-3 mol. When the amount of the oxidizing agent used is within the above range, the conductive polymer can be sufficiently polymerized and the main chain can be oxidized sufficiently.
It is also effective to use a transition metal compound such as iron or copper in combination with an oxidizing agent as a catalyst.

<Polymerization process>
The conductive polymer precursor is chemically oxidatively polymerized with an oxidizing agent in a solution containing a basic compound to obtain a conductive polymer (polymerization step).
Specifically, a method of dropping a mixed solution of a conductive polymer precursor and a basic compound into an oxidant solution, a method of dropping an oxidant solution into a mixed solution of a conductive polymer precursor and a basic compound, a reaction vessel For example, a method in which a mixed solution of a conductive polymer precursor and a basic compound and an oxidizing agent solution are dropped simultaneously, etc., a mixed solution of a conductive polymer precursor and a basic compound, and an oxidizing agent solution are continuously added to a reaction vessel or the like. The conductive polymer is obtained by a method such as feeding and polymerizing by an extrusion flow. In particular, from the viewpoint of suppressing side reactions, a method of dropping a mixed solution of a conductive polymer precursor and a basic compound into an oxidant solution is preferable.

In the polymerization, water or a mixed solvent of water and a water-soluble organic solvent can be used. The water-soluble organic solvent is not limited as long as it is mixed with water, but from the viewpoint of being inexpensive and easily available, for example, methanol, ethanol, iso-propanol, acetone, acetonitrile and the like are preferably used.
In addition, when using a mixed solvent, it is preferable that the ratio of water is 30 volume% or more in 100 volume% of mixed solvents. If the ratio of water is 30% by volume or more, precipitation of the oxidizing agent can be suppressed.

  Moreover, at the time of superposition | polymerization, it is preferable to adjust so that pH in a polymerization reaction system may be 7 or less, More preferably, pH is 6 or less. Here, if the pH in the polymerization reaction system is 7 or less, the progress of the side reaction can be suppressed, and as a result, the generation of impurities and oligomer (excluding dimer) components can be reduced, and the conductivity of the resulting polymer can be reduced. , Film formability, purity and the like are improved.

The pH in the reaction system during the polymerization can be adjusted by adding a protonic acid.
Protic acids include mineral acids such as hydrochloric acid, nitric acid, sulfuric acid and boric fluoride, super strong acids such as trifluoromethanesulfonic acid, organic sulfones such as methanesulfonic acid, dodecylbenzenesulfonic acid, toluenesulfonic acid and camphorsulfonic acid. Examples thereof include acids and polymer acids such as polystyrene sulfonic acid, polyacrylic acid, polyvinyl sulfonic acid, poly-2-methylpropane-2-acrylamide sulfonic acid, and the like. Among these, hydrochloric acid, nitric acid, sulfuric acid, p-toluenesulfonic acid and the like are preferable from the viewpoint of being inexpensive and easily available.

  The amount of the protonic acid added is not particularly limited as long as no oxidizing agent is precipitated, but the molar ratio is preferably protonic acid: oxidant = 0.01: 100 to 50: 100, 0.01: 100 to 45 : 100 is more preferable. Here, if the addition amount of the protonic acid is within the above range, it is difficult to hinder the progress of the reaction, and the precipitation of the dimer can be suppressed. As a result, the generation of impurities and oligomer components is suppressed, and the conductivity, film formability, purity, and the like of the resulting conductive polymer are improved.

  The internal temperature of the polymerization reaction is preferably 50 ° C. or less, more preferably −15 to 50 ° C., further preferably −10 to 20 ° C., and most preferably −5 to 15 ° C. In particular, when the temperature is 20 ° C. or lower, it is possible to suppress a decrease in conductivity due to a side reaction or a change in the redox structure of the main chain. Moreover, sufficient reaction rate can be maintained above -15 degreeC, and reaction time can be shortened.

<Purification process>
The conductive polymer is obtained in the state of a polymer solution dissolved or dispersed in a solvent. The conductive polymer may be used as it is for various applications after removing the solvent, but the polymer solution may contain unreacted dimers, oligomers, impurities, and the like. Therefore, it is preferable to use the conductive polymer after purification (purification step).
Hereinafter, the conductive polymer before purification is referred to as “unpurified conductive polymer”.

Examples of a method for purifying an unpurified conductive polymer include a membrane filtration method and a cation exchange method. Among these, a membrane filtration method is preferable from the viewpoint of excellent purification efficiency.
Examples of the membrane filtration method include filtration methods such as a cross flow method and a pressure filtration method.
When purifying an unpurified conductive polymer by the above-described method, the polymer solution can be used for purification as it is.

<Desalting step>
As described above, the conductive polymer is obtained by polymerizing a conductive polymer precursor in the presence of a basic compound. Therefore, some of the acidic groups in the conductive polymer may form a salt with the basic compound, and may become conductive. When an acidic group and a basic compound form a salt, the conductivity may decrease.

Basic compounds are generally removed together with low molecular weight substances and impurities when purifying an unpurified conductive polymer. For the purpose of further removing basic compounds, further desalting treatment is performed after the purification step. (Desalting step). In addition, when performing a desalting process, the sample liquid after a refinement | purification process can be used as it is.
Examples of the desalting treatment include an ion exchange method, and specific examples include an ion exchange method using a cation exchange resin and an electrodialysis method.

By the desalting treatment, the basic compound can be effectively removed from the conductive polymer, and the conductivity of the conductive polymer is further improved.
In addition, since the conductive polymer after the purification step and the desalting treatment is in a state dissolved in a solvent such as water, a solid conductive polymer can be obtained by removing the solvent with an evaporator or the like. You may use the thing in the state melt | dissolved in as a conductive polymer solution as it is.

<Other embodiments>
The manufacturing method of a conductive polymer is not limited to the method mentioned above. Although the manufacturing method mentioned above is a method of manufacturing a conductive polymer by chemical polymerization, you may manufacture a conductive polymer by electrolytic polymerization, for example.
When producing a conductive polymer by electrolytic polymerization, for example, an electrolytic polymerization solution containing the conductive polymer precursor of the present invention, an electrolyte, and a basic compound is prepared, and a working electrode, a counter electrode, and a reference electrode are immersed in the electrolytic polymerization solution. Let In this state, a voltage is applied between the working electrode and the counter electrode to form a film made of a conductive polymer on the working electrode, and the film is peeled off from the working electrode to obtain a conductive polymer. You may refine | purify the obtained conductive polymer as needed.
As an electrolyte used for electrolytic polymerization, an electrolyte used for normal electrolytic polymerization can be used, and examples thereof include anhydrous sodium sulfate.
Moreover, as a basic compound, the basic compound illustrated previously in description of chemical polymerization is mentioned.
Examples of the purification method include the purification method (purification step) exemplified above in the description of chemical polymerization.

<Effect>
The conductive polymer thus obtained is obtained by polymerizing the conductive polymer precursor of the present invention. As described above, the conductive polymer precursor of the present invention is a dimer having one or more electron donating groups in the molecule. Therefore, the conductive polymer of the present invention has a linear structure and is considered to exhibit high conductivity.

In particular, a conductive polymer obtained by polymerizing a conductive polymer precursor having one acidic group or a salt thereof in the molecule is linear and has aniline units, for example, as in the following compound (17). Since it is considered that it has a structure in which every other acidic group is introduced when it is used as a reference, it is considered that it exhibits higher conductivity.
The compound (17), as the conductive polymer precursor, in the general formula ^{(1), R 1, R} 2, R 5 ~R 7, R 9, R 10 is a hydrogen ^atom, R ^{3, R 11} Is a polymer obtained by polymerizing the following compound (1-2), wherein is a methoxy group (electron-donating group), R ⁴ is an amino group, and R ⁸ is a sulfonic acid group (acidic group).

Y in the compound (17) indicates the degree of polymerization.
This compound (17) is considered to have a phenylenediamine structure (reduced form) and a quinodiimine structure (oxidized form), and the phenylenediamine structure (reduced form) and the quinodiimine structure (oxidized form) are oxidized or reduced. It is possible to convert reversibly at an arbitrary ratio. The ratio (x) of the phenylenediamine structure to the quinodiimine structure is preferably in the range of 0.1 ≦ x ≦ 0.9 from the viewpoint of conductivity and solubility, more preferably 0.2 ≦ x ≦ 0.8, and More preferably, 3 ≦ x ≦ 0.7.

  The conductive polymer of the present invention can be dissolved in mere water, water containing a base and a basic salt, water containing an acid, or a solvent such as methanol, ethanol, iso-propanol, or a mixture thereof. Excellent workability.

In the present invention, the conductive polymer obtained by the above method may be used as it is, or an external dopant may be added. Although it does not specifically limit as an external dopant, For example, halogen atoms (for example, halogen atoms, such as iodine, bromine, and chlorine), protonic acid (for example, hydrochloric acid, sulfuric acid, perchloric acid, nitric acid, borofluoric acid, benzenesulfonic acid, p 1 And toluene ions such as toluenesulfonic acid, dodecylbenzenesulfonic acid, poly (styrenesulfonic acid), and complex ions (eg, hexacyanoiron (II) ion, tetrachloroplatinum (II) ion, etc.). Moreover, these external dopants may be used individually by 1 type, and may mix and use 2 or more types by arbitrary ratios.
When adding an external dopant, the addition amount is preferably 0.1 to 1.0 mol with respect to 1 mol of the nitrogen atom of the conductive polymer from the viewpoint of conductivity and film formability.

The conductive polymer of the present invention forms a conductor by a simple method such as spray coating, dip coating, roll coating, gravure coating, reverse coating, roll brushing, air knife coating, or curtain coating. can do.
Compositions based on conductive polymers include various antistatic agents, capacitors, batteries, EMI shields, chemical sensors, display elements, nonlinear materials, anticorrosion, adhesives, fibers, antistatic paints, anticorrosion paints, electric It can be applied to coating paint, plating primer, electrostatic coating base, cathodic protection, and battery storage capacity improvement.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.
In addition, the measurement / evaluation method in an Example and a comparative example is as follows.

(Identification of conductive polymer precursor)
^The conductive polymer precursor was identified by measuring the ¹ H-NMR spectrum. This measurement is carried out using FT-NMR (“JNM-GX270” manufactured by JEOL Ltd.) so that the concentration of the mixed solution of deuterated dimethyl sulfoxide and sodium hydroxide is about 5% by mass. A solution in which the conductive polymer precursor was dissolved was placed in a test tube having a diameter of 5 mmΦ, and the measurement was performed at a measurement temperature of 25 ° C., a measurement frequency of 270 MHz, and a single pulse mode with 64 integrations.

(Measurement of surface resistance)
A conductive polymer solution is spin-coated on a 5 cm × 5 cm glass substrate (300 rpm × 5 sec, then 2000 rpm × 30 sec), and heated on a hot plate at 120 ° C. for 10 minutes to form a coating having a thickness of 0.1 μm. A test piece having a film formed on a glass substrate was obtained.
The surface resistance value (initial value) of the obtained test piece was measured by attaching a series four-probe probe to a resistivity meter (manufactured by Mitsubishi Analytech Co., Ltd., “Loresta GP”).

[Example 1]
<Synthesis of conductive polymer precursor>
(A) Process:
25 g (149 mmol) of 2-methoxy-4-nitroaniline (5-1) was dissolved in 200 mL of tetrahydrofuran (THF). To this was added 45 mL (180 mmol) of 4M aqueous sodium hydroxide solution, and then 28.5 g (167 mmol) of benzyl chloroformate (P) was added with ice cooling, and the mixture was warmed to room temperature and stirred for 2 hours. Further, an operation of adding an aqueous sodium hydroxide solution and benzyl chloroformate (P) and stirring for 2 hours at room temperature were repeated twice.
Thereafter, the reaction solution was neutralized with 2N hydrochloric acid and stirred at room temperature. Subsequently, the reaction solution was extracted three times with 300 mL of toluene, and the obtained organic phase was washed twice with 100 mL of a sodium chloride aqueous solution. Thereafter, the solvent was distilled off under reduced pressure, and the residue was purified by column chromatography (developing solvent: mixed solvent of n-hexane and ethyl acetate) to obtain 39.8 g of compound (6-1) (yield). 89%).

(B) Process:
(B) Before the step, first, pretreatment of zinc powder was performed. To 150 mL of 1N hydrochloric acid was added 60.08 g of zinc powder, and the mixture was stirred at room temperature for about 10 minutes. After suction filtration, rinsing with water was performed, and suction filtration was performed as it was to obtain a wet powder.
Subsequently, 31.8 g (105 mmol) of the compound (6-1) was dissolved in 320 mL of toluene. Further, 88 mL of acetic acid was added, and then the zinc powder that had been pretreated while cooling with ice was gradually added. After raising the temperature to room temperature and stirring for 2 hours, the solid content was removed by filtration, and the solid content was washed with 200 mL of toluene to obtain an organic phase. After adding 50 mL of water to the organic phase, neutralization was performed with an aqueous sodium hydroxide solution. Thereafter, the organic phase was separated, and the aqueous phase was extracted twice with 100 mL of ethyl acetate. The obtained organic phases were combined and washed with a saturated aqueous solution of sodium bicarbonate until the aqueous phase became neutral. Thereafter, the solvent was distilled off under reduced pressure, and the residue was purified by column chromatography (developing solvent: mixed solvent of n-hexane and ethyl acetate) to obtain 21.9 g of compound (7-1) (yield). 76%).

(C) Process:
Into the flask was weighed 0.18 g (0.8 mmol) of palladium acetate and 0.75 g (1.2 mmol) of (±) -2,2′-bis (diphenylphosphino) -1,1′-binaphthyl. After purging with nitrogen, 20 mL of toluene and 20 mL of triethylamine were added. After stirring at 50 ° C. for 1 hour, 9.37 g (50 mmol) of 2-bromoanisole (8-1) was added and stirred for 30 minutes.
Subsequently, 10.4 g (38 mmol) of compound (7-1) was dissolved in 60 mL of toluene and added, and 5.45 g (57 mmol) of sodium t-butoxide (tBuONa) was further added. After heating up to 90 degreeC and stirring for 5 hours, it cooled to room temperature, the reaction liquid was suction-filtered and solid content was removed. The solid content was washed with toluene. The resulting organic phase was washed twice with 20 mL of water. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography (developing solvent: mixed solvent of n-hexane and ethyl acetate) to obtain 3.3 g of Compound (9-1) (23% yield). ).

(D) Process:
3.24 g (8.6 mmol) of compound (9-1) is weighed into a flask, and 30 mL of methanol, 30 mL of acetic acid, 10 mL of water, and 0.16 g (5% by mass) of 5% palladium carbon (Pd-C) are added thereto. did. After purging the flask with hydrogen, the mixture was stirred at room temperature (25 ° C.) for 4 hours. The reaction solution was filtered, and the solid content was washed with methanol. The obtained liquid was neutralized with an aqueous sodium hydroxide solution, and the aqueous phase was extracted three times with 80 mL of toluene. The obtained organic phases were combined and washed with 20 mL of a sodium chloride aqueous solution. The solvent was distilled off under reduced pressure, and the residue was purified by column chromatography (developing solvent: mixed solvent of n-hexane and ethyl acetate) to obtain 1.07 g of compound (10-1) (51% yield). ).

(E) Process:
0.65 g (2.7 mmol) of compound (10-1) was weighed into a flask, added to 28 g of concentrated sulfuric acid, and stirred at room temperature (25 ° C.). After confirming the consumption of the compound (10-1) by thin layer chromatography, the reaction solution was added dropwise to 300 g of a 10% by mass sodium chloride aqueous solution and cooled at about 5 ° C. The formed precipitate was filtered and rinsed with water. Then, it dried under reduced pressure, heating at 40 degreeC, and obtained 0.78g of compounds (1-2) (yield 90%).

The ¹ H-NMR spectrum of the compound (1-2) is shown in FIG. 1, and the assignment of the NMR spectrum is shown below.
¹ H-NMR (270 MHz in DMSO / D ₂ O): δ 7.18 (s, 1H), δ 6.97 (d, 1H, J = 8.2 Hz), δ 6.83 (d, 1H, J = 8. 4 Hz), δ 6.62 (d, 1 H, J = 8.1 Hz), δ 6.60 (s, 1 H), δ 6.52 (d, 1 H, J = 8.1 Hz), δ 3.70 (s, 3 H) , Δ 3.67 (s, 3H).

<Manufacture of conductive polymer (P-1)>
50 mmol of the conductive polymer precursor (compound (1-2)) and 50 mmol of triethylamine were dissolved in 26 g of a mixed solvent of water: acetonitrile = 1: 1 (volume ratio).
Separately, a solution obtained by dissolving 50 mmol of ammonium persulfate and 0.25 g of 98% by mass sulfuric acid in 52 g of a mixed solvent of water: acetonitrile = 1: 1 (volume ratio) was cooled in an ice bath. On the other hand, the conductive polymer precursor (compound (1-2)) and triethylamine solution were added dropwise over 1 hour. The stirring speed at this time was 200 rpm.
After completion of the dropwise addition, the system was kept cooled for 1 hour, then returned to an internal temperature of 25 ° C., and further stirred for 1 hour to obtain a polymer slurry.

Subsequently, 35 g of the obtained polymer slurry was diluted 8 times with ultrapure water (Millipore) to obtain 280 g of an aqueous solution.
It is obtained in a pressure type ultrafiltration unit (Advantech Co., Ltd., “Agitated Ultra Holder”) equipped with a pressure type ultrafiltration membrane (Advantech Co., Ltd., “Ultra Filter Q0100”) having a molecular weight cut off of 10,000 Da. The aqueous solution was set and filtered while pressurizing at a pressure of 0.35 MPa until the slurry became 30 g. Thereafter, the pressure was released, 250 g of ultrapure water (Millipore) was added to the concentrated slurry, and filtration was performed while applying pressure again. This operation was repeated three times to purify the unpurified conductive polymer, and the filter residue was lyophilized and recovered as a conductive polymer.

Next, 10 mL of a 1M pyridine solution was added to 0.5 g of the lyophilized conductive polymer and dissolved, and this was filtered off with an ultrafilter. Furthermore, 15 mL of 0.1 M hydrochloric acid aqueous solution and 15 mL of ethanol were added, and the operation of separating with an ultrafilter was repeated three times. Subsequently, the solution was filtered with 30 mL of 1M pyridine aqueous solution three times with an ultrafilter, and then filtered with 30 mL of ultrapure water (Millipore) three times with an ultrafilter, and the resulting slurry was lyophilized. Thus, 0.373 g of the ion-exchanged conductive polymer (P-1) was obtained (ion exchange treatment).
0.2 g of the conductive polymer (P-1) after the ion exchange treatment was dissolved in 10 mL of methanol to obtain a conductive polymer (P-1) solution, and the surface resistance value was measured. The results are shown in Table 1.

[Example 2]
<Synthesis of conductive polymer precursor>
(I) Process:
25 g (114 mmol) of 4-bromo-2-fluoro-1-nitrobenzene (14-1) was dissolved in 500 mL of methanol. To this, 26 g (136 mmol) of a methanol solution of 28% by mass sodium methoxide (MeONa) was added dropwise over 30 minutes at an internal temperature in the range of 20 to 25 ° C., followed by stirring for 2 hours. The reaction solution was concentrated, extracted twice with 250 mL of ethyl acetate, and then washed with 300 mL of pure water. Thereafter, the solvent was distilled off under reduced pressure to obtain 24.6 g of 4-bromo-2-methoxy-1-nitrobenzene (compound (11′-1)) (yield 93%).

(F) Process:
Into the flask was weighed 0.35 g (1.6 mmol) of palladium acetate and 1.55 g (2.5 mmol) of (±) -2,2′-bis (diphenylphosphino) -1,1′-binaphthyl. After replacing with nitrogen, 36 mL of toluene and 18 mL of triethylamine were added. After stirring at 50 ° C. for 1 hour, 18.0 g (77.6 mmol) of the compound (11′-1) was added and stirred for 30 minutes.
Subsequently, 9.6 g (77.6 mmol) of o-anisidine (compound (12-1)) was added after being dissolved in 45 mL of toluene, and 11.2 g (116.3 mmol) of sodium t-butoxide (tBuONa) was further added. did. After heating up to 80 degreeC and stirring for 5 hours, it cooled to room temperature, the reaction liquid was suction-filtered and solid content was removed. The solid content was washed with toluene. The resulting organic phase was washed twice with 20 mL of water. After distilling off the solvent under reduced pressure, crystallization was performed with 2-propanol to obtain 15.3 g of Compound (13-1) (yield 72%).

(G) Process:
To the flask, 6.0 g (21.9 mmol) of the compound (13-1) was weighed, and 120 mL of methanol and 0.6 g (10 mass%) of 5% by mass palladium carbon (Pd—C) were added thereto. The inside of the flask was pressurized with hydrogen to 0.4 MPa, and then stirred at 40 to 45 ° C. for 8 hours. Then, it cooled to room temperature, filtered the reaction liquid, and wash | cleaned solid content with methanol. The solvent was distilled off from the obtained filtrate under reduced pressure to obtain 5.0 g of Compound (10-1) (yield 93%).

(H) Process:
In the same manner as in the step (e) of Example 1, the compound (10-1) was sulfonated to obtain 0.78 g of the compound (1-2) (yield 90%).

The ¹ H-NMR spectrum of the compound (1-2) obtained in Example 2 was the same as that of the compound (1-2) obtained in Example 1.

<Manufacture of conductive polymer (P-2)>
A solution prepared by dissolving 50 mmol of the conductive polymer precursor (compound (1-2)) obtained in Example 2 and 50 mmol of pyridine in 80 g of water was cooled in an ice bath. On the other hand, a solution obtained by dissolving 50 mmol of ammonium persulfate in 50 g of water was added dropwise over 5 hours. The stirring speed at this time was 200 rpm.
After completion of dropping, cooling was maintained for 48 hours to obtain a polymer slurry.

Subsequently, the obtained polymer slurry was centrifuged to obtain a blue-green gel-like precipitate.
The obtained gel-like precipitate was re-dispersed in 100 g of water, and a pressure-type ultrafiltration unit (Advantech Co., Ltd.) equipped with a pressure-type ultrafiltration membrane (Advantech Co., Ltd., “Ultrafilter Q0100”) with a molecular weight cut off of 10,000 Da. It was set in a company, “stirring type ultra holder”) and filtered while being pressurized at a pressure of 0.35 MPa until the slurry became 30 g. Thereafter, the pressure was released, 250 g of ultrapure water (Millipore) was added to the concentrated slurry, and filtration was performed while applying pressure again.
This operation was repeated three times to purify the unpurified conductive polymer, and the filter residue was lyophilized and recovered as a conductive polymer (P-2).

  Subsequently, 0.2 g of freeze-dried conductive polymer (P-2) was dissolved in 10 mL of methanol to obtain a conductive polymer (P-2) solution, and the surface resistance value was measured. The results are shown in Table 1.

[Example 3]
<Production of conductive polymer (P-3)>
In the same manner as in Example 2, a polymer slurry was prepared using the conductive polymer precursor (Compound (1-2)) obtained in Example 2, and the gel-like precipitate obtained by centrifugation was purified. The residue was lyophilized and recovered as a conductive polymer (P-2).
Next, 0.2 g of freeze-dried conductive polymer (P-2) and 0.05 g of dodecylbenzenesulfonic acid were dissolved in 10 mL of methanol to obtain a conductive polymer (P-3) solution, and the surface resistance value was measured. The results are shown in Table 1.

[Example 4]
<Manufacture of conductive polymer (P-4)>
An electropolymerization solution obtained by dissolving 0.1281 g of the conductive polymer precursor (compound (1-2)) obtained in Example 2, 0.1307 g of morpholine, and 0.4261 g of anhydrous sodium sulfate in 15 mL of ultrapure water. Was prepared.
As the working electrode and the counter electrode for electrolytic polymerization, a platinum plate (manufactured by Hokuto Denko Co., Ltd.) having a size of 1 cm × 2 cm was used. As a reference electrode, a silver / silver chloride electrode (3M NaCl aqueous solution) (manufactured by BAS Co., Ltd.) was used.
A working electrode, a counter electrode, and a reference electrode are immersed in an electrolytic polymerization solution, a constant voltage of 1.4 V is applied between the working electrode and the counter electrode, and electropolymerization is performed for 30 minutes, and a film made of a conductive polymer is formed on the working electrode. Formed.
The resulting film was peeled off from the working electrode by washing with ultrapure water, and this was removed using an ultrafiltration unit (“USY-1” manufactured by Advantech Toyo Co., Ltd.) having a molecular weight cut off of 10,000 MWCO. Filter until no more. Furthermore, 2 mL of ultrapure water was added to the filtrate, and the operation of filtering and washing was repeated three times to obtain a conductive polymer (P-4).
The obtained conductive polymer (P-4) was dissolved in 0.3 mL of methanol to obtain a conductive polymer (P-4) solution, and the surface resistance value was measured. The results are shown in Table 1.

[Comparative Example 1]
<Manufacture of conductive polymer (P-5)>
A solution prepared by dissolving 0.56 g of ammonium persulfate in 98.0 mL of 3M aqueous hydrochloric acid was cooled in an ice bath.
Separately, 2.00 g of 4-aminodiphenylamine-2-sulfonic acid was dissolved in 29.4 mL of 1M aqueous sodium hydroxide and 294 mL of ultrapure water (Millipore), and cooled in an ice bath. On the other hand, a solution of ammonium persulfate was dropped over 5 minutes and stirred with a magnetic stirrer.
After completion of the dropwise addition, cooling was maintained for 2 hours, and then the internal temperature was returned to 25 ° C.

Subsequently, the obtained solution was subjected to a pressurized ultrafiltration unit (Advantech Co., Ltd., “Ultra Filter Q0100”) having a molecular weight cut-off of 10,000 Da. It was set in a holder “) and filtered while being pressurized at a pressure of 0.35 MPa until the slurry became 30 g. Thereafter, the pressure was released, 250 g of ultrapure water (Millipore) was added to the concentrated slurry, and filtration was performed while applying pressure again. This operation was repeated three times to purify the unpurified conductive polymer, and the filter residue was lyophilized to recover 0.86 g of the conductive polymer (P-5).
0.2 g of the obtained conductive polymer (P-5) was dissolved in 10 mL of methanol to obtain a conductive polymer (P-5) solution, and the surface resistance value was measured. The results are shown in Table 1.

As is clear from Table 1, the conductive polymers (P-1) to (P-4) obtained in Examples 1 to 4 have a surface resistance value of 3.1 × 10 ⁷ Ω / □ or less, It showed high conductivity. In particular, the conductive polymer (P-3) to which dodecylbenzenesulfonic acid was added as an external dopant and the conductive polymer (P-4) obtained by electrolytic polymerization showed high conductivity.
On the other hand, since the resistance of the conductive polymer (P-5) obtained in Comparative Example 1 was too large, the surface resistance value could not be measured. That is, it is shown that the conductive polymer (P-5) of Comparative Example 1 has insufficient conductivity compared to the conductive polymers (P-1) to (P-4) of Examples 1 to 4. It was.

Claims (3)

A conductive polymer precursor represented by the following general formula (1).

In formula (1), R ¹ is a hydrogen atom or a linear or branched alkyl group, wherein the nitrogen atom to which R ¹ is bonded forms a secondary or tertiary amino group or a salt thereof. R ^{2 to} R ¹¹ are each independently a hydrogen atom, an electron donating group, a hydroxyl group, a nitro group, a halogen atom, a cyano group, an alkylcarbonyloxy group, an amino group or a salt thereof, and an acidic group or a salt thereof. At least one of R ^{2 to} R ¹¹ is a hydrogen atom, at least one is an electron donating group, at least one is an amino group or a salt thereof, and at least one of R ^{2 to} R ¹¹ is selected from the group consisting of Is an acidic group or a salt thereof. A conductive polymer precursor represented by the following general formula (2).

In formula (2), R ^{12 to} R ¹⁹ are each independently a group consisting of a hydrogen atom, an electron donating group, a hydroxyl group, a nitro group, a halogen atom, a cyano group, an alkylcarbonyloxy group and an acidic group or a salt thereof. And at least one of R ^{12 to} R ¹⁹ is an electron donating group, at least one is an acidic group or a salt thereof, and R ²⁰ is an amino group or a salt thereof.   A conductive polymer obtained by polymerizing the conductive polymer precursor according to claim 1.

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