JP3402961B2 - Method for producing high-purity soluble aniline-based conductive polymer - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a high-purity aniline-based conductive polymer soluble in water or an organic solvent. The polymer can form a conductor by a simple method such as a spray coating method, a dip coating method, a roll coating method, a gravure coating method, a reverse coating method, a roll brushing method, an air knife coating method and a curtain coating method. . Further, the composition containing the polymer as a main component is used for various antistatic agents, capacitors, batteries, EMI shields, chemical sensors, display elements, nonlinear materials, anticorrosion,
It can be applied to adhesives, fibers, antistatic paints, anticorrosive paints, electrodeposition paints, plating primers, bases for electrostatic coating, cathodic protection, and improvement of battery storage capacity. Examples of applications of the antistatic agent include packaging materials, magnetic cards, magnetic tapes, magnetic discs, photographic films, printing materials, release films, heat seal tapes / films IC trays, IC carrier tapes, cover tapes and the like. .

[0002]

2. Description of the Related Art Although doped polyaniline (conductive polymer) is well known, it is insoluble in almost all solvents and has a problem in molding and processing. Also, a method of electrolytically oxidatively polymerizing aniline [JP-A-60-23583]
No. 1, gazette, J. Polymer Sci. Polyme
r Chem. Ed. , 26, 1531 (198
8)] makes it possible to form a polyaniline film on the electrode, but there are problems that the isolation operation becomes complicated and mass synthesis is difficult.

In recent years, alkali-soluble sulfonated polyaniline which exhibits conductivity without adding a doping agent and its synthesis method, and carboxylated polyaniline and its synthesis method have been proposed.

As a method of synthesizing sulfonated polyaniline, for example, a method of electrochemically polymerizing aniline and m-aminobenzenesulfonic acid to synthesize sulfonated polyaniline (Journal of the Chemical Society of Japan, 1985, 1124, JP-A-02- No. 166165), a method for synthesizing a sulfonated polyaniline by electrochemically polymerizing o-, m-, and p-aminobenzenesulfonic acid alone [Proceedings of the 64th Autumn Meeting of the Chemical Society of Japan II 706 ( 199
2)], a method of chemically polymerizing aniline and o-, m-aminobenzenesulfonic acid to synthesize a sulfonated polyaniline (JP-A-01-301714), an aminobenzenesulfonic acid compound or an aminobenzenesulfonic acid A method of chemically oxidatively polymerizing a monomer containing a compound based compound and an aniline compound (JP-A-6-56987),
A method of sulfonating an emeraldine type polymer (polyaniline) obtained by chemical or electrochemical polymerization with concentrated sulfuric acid (Japanese Patent Laid-Open No. 58-210902), sulfone using a sulfuric anhydride / triethyl phosphate complex. (JP-A-61-197633), a method of sulfonating with fuming sulfuric acid [J. Am. Chem. Soc. , (1
991) 113, 2665-2671, J. Am. Ch
em. Soc. , (1990) 112, 2800, WO
91-06887], a method for chemically polymerizing diphenylamine-4-sulfonic acid (sodium salt) to synthesize an N-substituted sulfonated polyaniline [Polymer,
(1993) 34, 158-162] and the like are known.

A method for electrochemically polymerizing aniline and m-aminobenzenesulfonic acid to synthesize a sulfonated polyaniline (Journal of the Chemical Society of Japan, 1985, 1124, JP-A-02-166165) is such that the product is on the electrode. Therefore, there are problems that the isolation operation becomes complicated and mass synthesis is difficult.

[0006] In the proceedings of the 64th Annual Meeting of the Chemical Society of Japan, II, 706 (1992), a method for synthesizing a soluble conductive polymer by electrolytic oxidation of aminobenzenesulfonic acid is explained. It is hard to say that it is suitable for large-scale synthesis. Further, it is described that no product was obtained when aminobenzenesulfonic acid was chemically oxidatively polymerized using ammonium peroxodisulfate as an oxidizing agent. Also, J. Am. Chem. Soc. , (1991) 11
According to 3,2665-2671, it was noted that attempts to chemically and electrochemically polymerize o-, m-aminobenzenesulfonic acid were unsuccessful.

Further, in JP-A-6-56987,
Aminobenzenesulfonic acid-based compound or a mixture of aminobenzenesulfonic acid-based compound and aniline-based compound is said to give a water-soluble conductive polymer by chemical oxidative polymerization in any of acidic, neutral and alkaline solutions. Although there is a description, and an example of polymerization in a sulfuric acid acidic solution is shown in Examples, there is no description about the molecular weight of the polymer and other physical properties, and it is not clear what kind of physical property the polymer was obtained. According to the additional test by the present inventors, a polymer having a sufficient molecular weight to form a film could not be obtained.

Further, the inventors of the present invention attempted polymerization in an aqueous solution containing a protic acid and in an aqueous solution using ammonium peroxodisulfate as an oxidizing agent, and obtained a water-soluble polymer, but having a low molecular weight. Therefore, it was not possible to obtain a practical polymer capable of forming a film.

A method for chemically polymerizing aniline and m-aminobenzenesulfonic acid with ammonium peroxodisulfate, which is described in JP-A-01-301714, and aniline and m, which are described in JP-A-6-56987. -When the present inventors supplemented the method of chemically polymerizing aminobenzene sulfonic acid with potassium permanganate, only about 1 sulfo group was introduced into 5 aromatic rings, and high conductivity was obtained. As shown, it was completely insoluble in neutral and acidic water, and almost insoluble in alkaline aqueous solutions such as ammonia. In addition, JP-A-61-19
In the case of sulfonation by the method of 7633, the same publication 7
As described on the page, since the solubility of polyaniline in the sulfonation solvent is not sufficient and the reaction is carried out in a dispersed state, only about 1 sulfo group is introduced into 5 aromatic rings. The thus-obtained sulfonated polyaniline having a small introduction ratio of sulfone groups has a problem that the conductivity and the solubility are not sufficient.

Further, J. Am. Chem. Soc. ，
(1991) 113, 2665-2671, J. Am.
Chem. Soc. , (1990) 112, 2800, describes that when polyaniline is sulfonated with fuming sulfuric acid, about 1 sulfone group is introduced into two aromatic rings. However, when it is attempted to sufficiently sulfonate polyaniline by this method, since the solubility of polyaniline in fuming sulfuric acid is not sufficient, fuming sulfuric acid is required in a large excess. Further, there is a problem that the polymer is easily solidified even when polyaniline is added to fuming sulfuric acid. Further, the polymer synthesized by the above method and its sulfonated compound have a problem that they are soluble in an aqueous solution containing ammonia and a base such as an alkylamine but not in water alone.

Further, Polymer (1993) 34,
According to 158-162, when diphenylamine-4-sulfonic acid (sodium salt) is polymerized, N-substituted sulfonated polyaniline in which one benzenesulfonic acid group is introduced to the aniline skeleton is obtained to give water alone. Although it also dissolves, it is described that an ultracentrifugation operation is necessary to isolate the polymer. As a result of additional tests by the present inventors, the yield of the polymerized product from the polymerization solvent is low due to its high solubility, and the polymerized product cannot be isolated unless the high-speed centrifugation operation is performed. It was In addition, since the N-position substitution type, J. Am. Chem. Soc. , (199
1) The conductivity was lower than that of the polymer synthesized by the method of 113,2665-2671.

As a method for synthesizing a carboxylated polyaniline, for example, a method for producing a carboxyl group in a salt form by oxidatively polymerizing 2- or 3-carboxyaniline or a salt thereof and then treating with a basic substance ( Japanese Patent Laid-Open No. Hei 4
No. 268331) has been proposed, but the amount of the oxidizer used is required to be equal to or more than twice the amount of the raw material, and the conductivity is low. From this, it is expected that a low-molecular weight polymer having low monomer reactivity is produced.

Also, a synthetic method in which methylanthranilate (anthranilic acid methyl ester) is polymerized in the presence of ammonium peroxodisulfate in an aqueous acidic medium, and then the methyl ester is saponified with alcoholic potassium hydroxide No. 5-226238) has been proposed, but the operation is extremely complicated because the reaction has two stages.

Further, when the present inventors tried polymerization of 2-carboxyaniline with ammonium peroxodisulfate as an oxidizing agent in an aqueous solution containing a protic acid, the product could not be obtained. Further, the inventors of the present invention tried to polymerize aniline and 2-carboxyaniline with ammonium peroxodisulfate as an oxidizing agent in an aqueous solution containing a protic acid. The sex was also low. From this, it is considered that the copolymer obtained has a low copolymerization ratio of 2-carboxyaniline.

Therefore, in order to develop conductivity and improve solubility without adding a doping agent to the polymer, it is necessary to introduce more acidic groups such as sulfone groups or carboxyl groups into the aromatic ring of the main chain. It is thought that there is.

In consideration of moldability such as film formation by coating, it should be soluble in both water and an organic solvent in order to be able to coat on both hydrophilic and hydrophobic substrates. Is desired. However, the sulfonated product of polyaniline is soluble in alkaline water but insoluble in neutral to acidic aqueous solutions, and its solubility in organic solvents is not sufficient.

As a method of solving these various problems,
The present inventors copolymerized at least one compound selected from the group consisting of aniline, N-alkylaniline and phenylenediamines with aminobenzene sulfonic acid using an oxidizing agent in an acidic solvent, and further sulfonating agent. A method for producing a sulfonated aniline-based copolymer, which is characterized in that it is sulfonated by the method described in Japanese Patent Application Laid-Open No. 5-1789.
No. 89). However, this method also requires an operation of sulfonation in concentrated sulfuric acid, and treatment of waste acid remains a big problem. All the copolymers synthesized by this method are presumed to have the structure of the following formula (4).

[0018]

[Chemical 4] (In the formula, R _26, R _27, R ₂₈ and R ₂₉ are each a group selected from the group consisting of hydrogen and a sulfone group,
R'is hydrogen or a group selected from the group consisting of alkyl groups having 1 to 4 carbon atoms, the proportion of sulfone groups is 40 to 80% of the content of sulfone groups in the aromatic ring, x is 0
Represents an arbitrary number of 1 to n, and n represents a degree of polymerization of 2 to 150
It is a number of zero. )

Further, the present inventors have found that aniline and N-
By copolymerizing at least one compound selected from the group consisting of alkylaniline and phenylenediamine with an alkoxy-group-substituted aminobenzene sulfonic acid, an aniline-based co-polymer which omits the sulfonation operation that generates a large amount of waste is generated. Method for producing coalescence (Japanese Patent Application No. 5-4854)
No. 0) was proposed. All the copolymers synthesized by this method are presumed to have the structure of the following formula (5).

[0020]

[Chemical 5] (In the formula, R _30, R _31, R _32, R _33, R _34, R _35, R ₃₆ and R ₃₇ are each a group selected from the group consisting of hydrogen, an alkoxy group and a sulfone group; The content of the sulfo group is 25 to 50% based on the aromatic ring, the alkoxy group and the sulfo group are contained in the same aromatic ring, and R ^" is hydrogen or an alkyl group having 1 to 4 carbon atoms. Which is a group selected from the group consisting of x, x represents an arbitrary number of 0 to 1, and n is a number of 2 to 1500 indicating the degree of polymerization.)

As the polymerization solvent in the above-mentioned chemical polymerization, water or an aqueous solution containing a protonic acid is used. For example, according to JP-A-1-163263, when ammonium peroxodisulfate is used as an oxidant, it is preferable that a pKa having a pKa of 3 or less is particularly contained, and aniline is used as a solvent in the polymerization of aniline.
It is described that a protic acid and an oxidizing agent that are dissolved and that are not oxidized by the oxidizing agent are used. In JP-A-4-268331, an aqueous solution of ammonium persulfate is added to an aqueous solution of anthranilic acid for oxidative polymerization, and the pH of the polymerization solvent is almost neutral.

[0022]

The object of the present invention is to:
Provided is a method for producing a high-purity soluble aniline-based conductive polymer which exhibits high conductivity, has excellent solubility in water or an organic solvent having any pH, and has excellent coatability and film strength. Especially.

[0023]

DISCLOSURE OF THE INVENTION The inventors of the present invention have proposed a method for producing a polyaniline having high conductivity and solubility, in which an acidic group-substituted polyaniline having a large ratio of introduction of an acidic group such as a sulfone group and / or a carboxyl group to an aromatic ring is introduced. As a result of diligent studies, polymerization of acidic group-substituted aniline such as sulfo group-substituted aniline and / or carboxyl group-substituted aniline as a monomer in a mixed solution of an aqueous solution containing a basic compound and an organic solvent mixed with water using an oxidizing agent. Then, the reactivity was remarkably improved, and it was found that a high molecular weight polymer can be produced, contrary to the established theory that the conventional aniline having a sulfone group or a carboxyl group is difficult to undergo chemical oxidative polymerization by itself. . Further, the obtained polymer is treated with an acid to further improve the conductivity and the solubility, and the composition containing these polymers as a main component has a good coatability, and the film strength after coating is also significantly improved. The present invention was found to be superior to the present invention, and the present invention was achieved.

That is, the present invention relates to the general formula (1)

[Chemical 6] (In the formula, R _1, R _2, R _3, R ₄ and R ₅ are each hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, respectively. , An acidic group, a hydroxyl group, a nitro group, and a halogen, at least one of which is an acidic group, and the acidic group is a sulfone group or a carboxyl group). At least one compound (a) selected from the group consisting of acidic group-substituted aniline, its alkali metal salt, alkaline earth metal salt, ammonium salt and substituted ammonium salt can be used in a basic compound (b) -containing aqueous solution and water. The following general formula (2) consists of polymerizing with an oxidizing agent in a mixed solution with a soluble organic solvent (C).

[Chemical 7] (In the formula, R _21, R _22, R ₂₃ and R ₂₄ are each hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, an acidic group , A hydroxyl group, a nitro group, and a halogen group, at least one of which is an acidic group, and the acidic group is a sulfone group or a carboxyl group). And a weight average molecular weight of 3000 or more and a residual monomer content of 3% by weight or less.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. A typical one represented by the general formula (1) is a sulfo group-substituted aniline or a carboxyl group-substituted aniline. The most representative of the sulfo group-substituted anilines are aminobenzenesulfonic acids, specifically, o-, m-, p-aminobenzenesulfonic acid, aniline-2,6-disulfonic acid, aniline-2,5. -Disulfonic acid, aniline-3,5-disulfonic acid, aniline-
2,4-Disulfonic acid and aniline-3,4-disulfonic acid are preferably used.

Other sulfo group-substituted anilines include methylaminobenzenesulfonic acid, ethylaminobenzenesulfonic acid, n-propylaminobenzenesulfonic acid, iso-propylaminobenzenesulfonic acid, n.
-Butylaminobenzenesulfonic acid, sec-butylaminobenzenesulfonic acid, t-butylaminobenzenesulfonic acid, and other alkyl-substituted aminobenzenesulfonic acids, methoxyaminobenzenesulfonic acid, ethoxyaminobenzenesulfonic acid, propoxyaminobenzenesulfonic acid, etc. Alkoxy group-substituted aminobenzene sulfonic acids, hydroxy group-substituted aminobenzene sulfonic acids, nitro group-substituted aminobenzene sulfonic acids, fluoroaminobenzene sulfonic acid, chloroaminobenzene sulfonic acid, bromoaminobenzene sulfonic acid, etc. Examples thereof include acids. Of these, alkyl group-substituted aminobenzene sulfonic acids, hydroxy group-substituted aminobenzene sulfonic acids and halogen group-substituted aminobenzene sulfonic acids are most preferable in practice. In addition, these sulfone group-substituted anilines may be used alone, or the isomers may be mixed at an arbitrary ratio.

The most typical carboxyl group-substituted anilines are aminobenzenecarboxylic acids, specifically o-, m-, p-aminobenzenecarboxylic acids,
Aniline-2,6-dicarboxylic acid, aniline-2,5-
Dicarboxylic acid, aniline-3,5-dicarboxylic acid, aniline-2,4-dicarboxylic acid, aniline-3,4-dicarboxylic acid and the like are preferably used.

Other carboxyl group-substituted anilines include methylaminobenzenecarboxylic acid, ethylaminobenzenecarboxylic acid, n-propylaminobenzenecarboxylic acid, iso-propylaminobenzenecarboxylic acid,
Alkyl group-substituted aminobenzenecarboxylic acids such as n-butylaminobenzenecarboxylic acid, sec-butylaminobenzenecarboxylic acid and t-butylaminobenzenecarboxylic acid, methoxyaminobenzenecarboxylic acid, ethoxyaminobenzenecarboxylic acid, propoxyaminobenzenecarboxylic acid Alkoxy group-substituted aminobenzenecarboxylic acids, hydroxy group-substituted aminobenzenecarboxylic acids, nitro group-substituted aminobenzenecarboxylic acids, fluoroaminobenzenecarboxylic acid, chloroaminobenzenecarboxylic acid, bromoaminobenzenecarboxylic acid, etc. Examples thereof include carboxylic acids. Among these, alkyl group-substituted aminobenzene carboxylic acids, alkoxy group-substituted aminobenzene carboxylic acids and halogen group-substituted aminobenzene sulfonic acids are most preferable in practical use. These carboxyl group-substituted anilines may be used alone, or the isomers may be mixed in an arbitrary ratio.

The acidic group-substituted aniline of the general formula (1) is a sulfone group-substituted alkylaniline, a carboxyl group-substituted alkylaniline, a sulfone group-substituted alkoxyaniline, a carboxyl group-substituted alkoxyaniline, a sulfone group-substituted hydroxyaniline, or a carboxyl group-substituted. Hydroxyaniline, sulfone group substituted nitroaniline, carboxyl group substituted nitroaniline, sulfone group substituted fluoroaniline, carboxyl group substituted fluoroaniline,
It can be expressed as either a sulfo group-substituted chloroaniline, a carboxyl group-substituted chloroaniline, a sulfone group-substituted bromaniline, or a carboxyl group-substituted bromaniline. Specific examples of the positions and combinations of these substituents are shown in Table 1. .

[0030]

[Table 1] Here, A: one group selected from a sulfonic acid group or a carboxylic acid group, an alkali metal salt, an ammonium salt, and a substituted ammonium salt thereof, B: a methyl group, an ethyl group, an n-propyl group, an iso-propyl group. Group, n-butyl group, sec-butyl group, alkyl group such as t-butyl group, methoxy group, ethoxy group, n
-A group selected from an alkoxy group such as a propoxy group, an iso-propoxy group, an n-butoxy group, a sec-butoxy group and a t-butoxy group, and a halogen group such as a hydroxy group, a fluoro group, a chloro group and a bromine group. H: hydrogen, methyl group, ethyl group, n-propyl group, is
o-propyl group, n-butyl group, sec-butyl group,
t-butyl group, methoxy group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, sec
One group selected from an alkyl group such as butoxy group, an alkoxy group, a hydroxy group, a nitro group, a fluoro group, a chloro group, and a halogen group such as a bromine group.

Examples of alkali metals in these monomers include lithium, sodium and potassium. Further, examples of the substituted ammonium include alicyclic ammonium, cyclic saturated ammonium, cyclic unsaturated ammonium and the like.

The lipophilic ammoniums are represented by the following formula (6)

[Chemical 8] (In the formula, R _{26 to} R ₂₉ are groups independently selected from the group consisting of hydrogen, an alkyl group having 1 to 4 carbon atoms, CH ₂ OH and CH ₂ CH ₂ OH.).

Specifically, methylammonium, dimethylammonium, trimethylammonium, ethylammonium, diethylammonium, triethylammonium, methylethylammonium, diethylmethylammonium, dimethylethylammonium, propylammonium, dipropylammonium, isopropylammonium, diisopropylammonium. , Butylammonium, dibutylammonium, methylpropylammonium, ethylpropylammonium, methylisopropylammonium, ethylisopropylammonium,
Methylbutylammonium, ethylbutylammonium, tetramethylammonium, tetramethylammonium, tetraethylammonium, tetra-n-butylammonium, tetrasec-butylammonium,
Tetra t-butylammonium etc. can be illustrated.

Examples of cyclic saturated ammoniums include piperidinium, pyrrolidinium, morpholinium, piperazinium and derivatives having these skeletons.

The cyclic unsaturated ammonium compounds include pyridinium, α-picolinium, β-picolinium, γ-.
Examples thereof include picolinium, quinolinium, isoquinolinium, pyrrolinium and derivatives having these skeletons.

Next, as the basic compound (b) used in the present invention, ammonia, aliphatic amines, cyclic saturated amines, cyclic unsaturated amines and the like are preferably used. Especially, aliphatic amines, cyclic saturated amines, cyclic unsaturated amines and the like are preferable.

Preferred aliphatic amines are represented by the following general formula (7)

[Chemical 9] (In the formula, R _{30 to} R ₃₂ are each an alkyl group having 1 to 3 carbon atoms, C
It is a group independently selected from the group consisting of H ₂ OH and CH ₂ CH ₂ OH. ) A compound represented by

Or the general formula (8)

[Chemical 10] (In the formula, each of R _{33 to} R ₃₆ is a group independently selected from the group consisting of hydrogen, an alkyl group having 1 to 3 carbon atoms, CH ₂ OH and CH ₂ CH ₂ OH.). Hydroxide compounds can be mentioned.

The cyclic saturated amines include piperidine,
Pyrrolidine, morpholine, piperazine, derivatives having these skeletons, and ammonium hydroxide compounds thereof are preferably used.

Examples of the cyclic unsaturated amines include pyridine,
[alpha] -picoline, [beta] -picoline, [gamma] -picoline, quinoline, isoquinoline, pyrroline, derivatives having these skeletons, and ammonium hydroxide compounds thereof are preferably used.

Of these basic compounds, particularly preferable are methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethylmethylamine, ethyldimethylamine, diethylmethylamine, pyridine, α-picoline,
Examples thereof include β-picoline and γ-picoline. When these are used, a polymer having a particularly high purity can be obtained.

The concentration of these basic compounds (b) is 0.
It is used in an amount of 1 mol / liter or more, preferably 0.1 to 10.0 mol / liter, and more preferably 0.2 to 8.0 mol / liter. If it is less than 0.1 mol / liter, the yield of the obtained polymer is lowered, and 10.
When it is more than 0 mol / liter, the conductivity tends to decrease. The basic compound (b) may be used alone or in combination of two or more.

The weight ratio of the compound (a) such as the acidic group-substituted aniline and the basic compound (b) is (a):
(B) = 1: 100 to 100: 1, preferably 10: 9
It is 0 to 90:10. Here, if the proportion of the basic compound is low, the reactivity tends to decrease and the conductivity also tends to decrease. On the contrary, when the ratio is high, the ratio of the acidic group and the basic compound in the obtained polymer to form a salt is high and the conductivity tends to be lowered.

Further, the molar ratio of the acidic group (e) to the basic compound (b) in the compound (a) such as aniline substituted with an acidic group is (e) :( b) = 1: 100 to 100: 1. , Preferably 1: 0.25 to 1:20, more preferably 1:
It is 0.5 to 1:15. Here, if the proportion of the basic compound is low, the reactivity tends to decrease and the conductivity also tends to decrease.
On the contrary, when the ratio is high, the ratio of the acidic group and the basic compound in the obtained polymer to form a salt is high and the conductivity tends to be lowered.

Polymerization or copolymerization is carried out by oxidative polymerization with an oxidizing agent in a mixed solution of an aqueous solution containing the basic compound (b) and an organic solvent (c) mixed with water. By using the mixed solution, the filterability of the polymer is remarkably improved, and the obtained polymer is highly purified. The organic solvent (c) is mixed with alcohols such as methanol, ethanol and isopropanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, and water such as acetonitrile, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and dimethyl sulfoxide. The organic solvent is preferably used. Especially methanol,
Preferred are ethanol, isopropanol, acetone, acetonitrile, dimethylformamide, dimethylsulfoxide and the like. These organic solvents may be used alone or in a mixture, or may be used in a mixture with water.

The mixing ratio (weight ratio) of water to the organic solvent is water: organic solvent (c) = 5: 95 to 95: 5, preferably 10:90 to 90:10, and more preferably 2
It is 0:80 to 80:20.

The standard electrode potential of the oxidizing agent is 0.6 V.
The oxidizing agent is not particularly limited as long as it is the above-mentioned oxidizing agent, but peroxodisulfates such as peroxodisulfate, ammonium peroxodisulfate, sodium peroxodisulfate, potassium peroxodisulfate and hydrogen peroxide are preferably used, and 1 mol of the monomer is used. On the other hand, it is used in an amount of 0.1 to 5 mol, preferably 0.5 to 5 mol. At this time, it is also effective to add a transition metal compound such as iron or copper as a catalyst.

The reaction temperature applied in the present invention is -15 to -15.
The temperature range is 70 ° C., preferably −10 to 60 ° C., and more preferably −5 to 40 ° C. Temperature is -15 ℃
If it is lower, the polymerization is not sufficient, and if it is higher than 70 ° C., a side reaction proceeds and the conductivity tends to decrease.

Hydrogen in the sulfone group or carboxyl group in the polymer produced by the present invention is hydrogen,
It is a group independently selected from the group consisting of alkali metals, ammonium and substituted ammonium, that is, these groups can be obtained in a mixed state rather than alone.

Specifically, when polymerized in the presence of sodium hydroxide, most of the hydrogens in the sulfone group or the carboxyl group in the isolated polymer are in the state of being replaced with sodium.

Similarly, the hydrogen in the sulfone group or carboxyl group in the polymer is mostly ammonium when polymerized in the presence of ammonia, and mostly trimethylammonium when polymerized in the presence of trimethylamine. When polymerized, the majority is obtained with quinolinium.

When basic compounds are mixed and used, they are obtained in a mixed state. Specifically, when polymerized with sodium hydroxide in the presence of ammonia, hydrogen at a sulfone group or a carboxyl group in the isolated polymer is obtained in the presence of both sodium and ammonium. Also, when the obtained polymer is treated with a solution in which both sodium hydroxide and ammonia are present, hydrogen in the sulfone group or carboxyl group in the polymer is similarly obtained in the presence of both sodium and ammonium.

The above-mentioned polymer in which some of the acidic groups form a salt can be treated with an acid-containing solution to obtain a polymer of higher purity.

Examples of the acid include mineral acids such as hydrochloric acid, nitric acid, sulfuric acid and fluoroboric acid, super strong acids such as trifluoromethanesulfonic acid, methanesulfonic acid, dodecylbenzenesulfonic acid, toluenesulfonic acid and camphorsulfonic acid. Examples of the group-substituted sulfonic acid include hydrochloric acid, nitric acid, sulfuric acid, p-toluenesulfonic acid, and the like. These solvents are not particularly limited as long as they can be mixed with these protonic acids, but alcohols such as methyl alcohol, ethyl alcohol, iso-propyl alcohol, n-propyl alcohol, t-butyl alcohol, acetone, methyl ethyl ketone, etc. , Ketones such as methyl isobutyl ketone, glycols, glycol ethers, acetonitrile, N, N-dimethylformamide,
N-methylpyrrolidone, dimethyl sulfoxide and the like are preferably used, and methyl alcohol, ethyl alcohol, iso-propyl alcohol, acetone and acetonitrile are particularly preferable. The concentration of the acid used here is
0.1 to 10 mol / liter, preferably 0.1 to 5 mol / liter is effective.

The polymer is isolated from the reaction solution by filtration, but unreacted monomers are dissolved in the reaction solution.
As the separation device used at this time, vacuum filtration, pressure filtration,
Centrifugal separation, centrifugal filtration, etc. are used, but especially centrifugal separation,
It is preferable to use a separation device such as centrifugal filtration. At the time of separation, if the temperature of the reaction solution is 5 ° C. or higher, the separation of by-products is improved, and a high-purity polymer can be obtained. The temperature range is 5 to 80 ° C, preferably 10 to 70 ° C, more preferably 15 to 60 ° C.

As the cleaning solvent, alcohols such as methyl alcohol, ethyl alcohol, iso-propyl alcohol, n-propyl alcohol, t-butyl alcohol, acetone, acetonitrile, N, N-dimethylformamide, N-methyl are used. Pyrrolidone, dimethyl sulfoxide and the like are used, and it is particularly effective to use methyl alcohol, ethyl alcohol, iso-propyl alcohol, acetone and acetonitrile.

According to the above method, the following general formula (2)

[Chemical 11] (In the formula, R _21, R _22, R ₂₃ and R ₂₄ are each hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, an acidic group , A hydroxyl group, a nitro group, and a halogen group, at least one of which is an acidic group, and the acidic group is a sulfone group or a carboxyl group). A soluble aniline-based conductive polymer having a weight average molecular weight of 3,000 or more, which mainly contains, is obtained. The purity of the polymer is such that the residual monomer is 3
wt% or less, 5 wt% or less of oligomers having an average weight molecular weight of 1100 or less, and 3 wt% of each of residual salt, acid, and base.
% Or less, preferably 2 wt% or less of residual monomers, 3 wt% or less of oligomers having an average weight molecular weight of 1100 or less, 2 wt% or less of residual salts, acids and bases, and more preferably 0.5 wt% or less of residual monomers, 1 wt% or less of an oligomer having an average weight molecular weight of 1100 or less,
Residual salt, acid and base are each 1 wt% or less, particularly preferably residual monomer is 0.5 wt% or less, oligomer having an average weight molecular weight of 1100 or less is 0.5 wt% or less, residual salt, acid and base are each 0 It has a high purity of 0.5 wt% or less. The higher the purity, the better the conductivity and solubility.

The weight average molecular weight of this polymer is 3
000-3,240,000, preferably 5000-
1,000,000, more preferably 10,000-
It is 500,000.

This polymer, without further sulfonation operation, contains water or water containing ammonia, a base such as alkylamine, a base such as ammonium acetate and ammonium oxalate and a basic salt, an acid such as hydrochloric acid and sulfuric acid, and the like. , Methyl alcohol, ethyl alcohol, isopropyl alcohol and the like, or a mixture thereof.

The polymer obtained by this method is
It can be expressed as having a phenylenediamine structure (reduced type) and a quinodiimine structure (oxidized type) represented by the following general formula (3).

[Chemical 12] (In the formula, R _{25 to} R ₄₀ are an electron withdrawing group, an acidic group, hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, and 1 to 4 carbon atoms.
4 is a linear or branched alkoxy group, a hydroxyl group, a nitro group, and a group selected from the group consisting of halogen,
At least one of them represents an acidic group. Moreover, an acidic group here shows a sulfone group or a carboxyl group. Among these, at least two of the four substituents on each aromatic ring are preferably a combination of an acidic group and an alkyl group, a hydroxyl group, a halogen group or an alkoxy group, and particularly preferably a combination of an acidic group and an alkoxy group.

The phenylenediamine structure (reduced type) and the quinodiimine structure (oxidized type) can be reversibly converted at an arbitrary ratio by oxidation or reduction. The ratio of the phenylenediamine structure to the quinodiimine structure is 0.2 <
The range of x <0.8 is preferable from the viewpoint of conductivity and solubility, and 0.3 <x <0.7 is more preferable. The above ratio is small when oxidized with an oxidizing agent such as benzoyl peroxide, ammonium peroxodisulfate and hydrogen peroxide, but is small when reduced with a reducing agent such as hydrazine, phenylhydrazine, sodium borohydride and sodium hydride. You get a big one.

Further, the high-purity soluble aniline-based conductive polymer of the present invention has an effect on solubility, conductivity and properties as a structural unit other than those represented by the above general formula (1) or general formula (2). Unless otherwise specified, it may include at least one structural unit selected from substituted or unsubstituted aniline, thiophene, pyrrole, phenylene and vinylene.

In this case, the repeating unit of the above general formula (1) or (2), that is, the content of the acidic group in the aromatic ring is 70% or more, preferably 80% or more,
More preferably, it should be contained at 90% or more. When the content is less than 70%, the solubility in water is insufficient, which is not preferable. The higher the content of the acidic group with respect to the aromatic ring, the better the solubility in water, and the content of the acidic group of 100% has the highest solubility.

[0064]

EXAMPLES The present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

[Measurement Method] The IR spectrum was measured using an apparatus manufactured by Perkin Elmer (Model 1600). For the measurement of the molecular weight distribution and the molecular weight, GPC measurement (polyethylene glycol conversion) was performed using a GPC column for aqueous solution. The column was used by connecting three types of gel filtration chromatography columns for aqueous solution. A 0.2 M phosphate buffer solution was used as the eluent. The analysis of acidic group-substituted aniline, residual salt, and acid in the polymer was carried out by using ion chromatography. The column used was an anion column, and the eluent used was 1 mmol / l acetate buffer. Conductivity is
The 4-terminal method was used for measuring the electrical conductivity, and the 2-terminal method was used for measuring the surface resistance. The pencil test method was used for the film strength.

Example 1 100 mmol of o-aminobenzenesulfonic acid was added at 25 ° C.
Was dissolved in a 4 mol / l trimethylamine solution (acetonitrile / water = 1/1; weight ratio) with stirring, and a solution of 100 mmol ammonium peroxodisulfate (acetonitrile / water = 1/1; weight ratio) was added dropwise. 2 after the dropping
After further stirring at 5 ° C. for 12 hours, the reaction product was filtered by a centrifugal filter, washed with methyl alcohol and dried to obtain 15 g of polymer powder. The volume resistance value of this product was 12.0 Ωcm. In addition, the residual monomer contained in this polymer was 1% for o-aminobenzenesulfonic acid, and 1% for the by-product salt trimethylamine sulfate.

3 parts by weight of the above polymer was dissolved in 100 parts by weight of water with stirring at room temperature to prepare a conductive composition. The solution thus obtained was applied on a glass substrate by spin coating and dried at 100 ° C. A film having a film thickness of 0.1 μm and a smooth surface resistance value of 1.0 × 10 ⁵ Ω / □ was obtained.

As a result of GPC measurement, the molecular weight of this product was number average molecular weight (Mn) 15,000 and weight average molecular weight (M
w) 19,000, Z average molecular weight (Mz) 2100
0, dispersity Mw / Mn = 1.3 and Mz / Mw = 1.1.

The above polymer was added little by little to 10 ml of water, a 0.1 mol / l sulfuric acid aqueous solution or 0.1 mol / l ammonia water, and when the polymer became insoluble, it was filtered to determine the amount of dissolution. The solubility of the polymer was as follows: water 350 mg / ml 0.1 mol / l sulfuric acid aqueous solution 295 mg / ml 0.1 mol / l ammonia water 400 mg / ml.

An IR spectrum of the polymer is shown in FIG. 1, ion chromatography of residual monomers and residual by-product salts in the polymer is shown in FIG. 2, and residual monomers in the polymer and basic compounds are analyzed by high performance liquid chromatography. A graph is shown in FIG. 3, and a GPC measurement chart in the polymer is shown in FIG. Assignment of IR spectrum is as follows. Sulfone group: Absorption near 1120,1020 cm | Polymer skeleton: Absorption near 1500 cm |

Example 2 100 mmol of 2-aminoanisole-4-sulfonic acid
Was dissolved in a 4 mol / l triethylamine solution (acetone / water = 1/1; weight ratio) at 5 ° C., and a 100 mmol ammonium peroxodisulfate solution (acetone / water = 1 /
(1; weight ratio) was added dropwise while cooling to 5 to 20 ° C. After completion of dropping, the reaction product was further stirred at 20 ° C. for 12 hours, separated by a centrifugal filter, washed with ethyl alcohol and then dried to obtain about 18 g of a polymer powder. The volume resistance value of this product was 10.0 Ω · cm. The residual monomer contained in this polymer, 2-aminoanisole-4-sulfonic acid, was 0.5%, and the by-product salt, triethylamine sulfate, was 0.4%.

5 parts by weight of the above polymer was dissolved in 100 parts by weight of a 0.2 mol / l sulfuric acid aqueous solution with stirring at room temperature to prepare a conductive composition. The solution thus obtained was applied on a glass substrate by spin coating and dried at 100 ° C. Membrane pressure 0.2μm, smooth surface resistance 1.0 ×
A film of 10 ⁵ Ω / □ was obtained.

Example 3 100 mmol of 2-aminophenol-4-sulfonic acid
Was dissolved in a 3 mol / l methylpyridine solution (acetonitrile / water = 3/7; weight ratio) at 5 ° C., and a 100 mmol ammonium peroxodisulfate solution (acetone / water =
(3/7; weight ratio) was added dropwise while cooling to 5 to 30 ° C. After the completion of dropping, the mixture was further stirred at 20 ° C. for 12 hours, and then the polymerization solution was heated to 40 ° C. After heating, the mixture was further stirred at 40 ° C. for 2 hours, the reaction product was separated by a centrifugal filter, washed with methyl alcohol and then dried to obtain about 15 g of a polymer powder. The volume resistance value of this product is 8.
It was 0 Ω · cm. The residual monomer contained in the polymer was 2-aminoanisole-4-sulfonic acid at 0.1%, and the by-product salt, methylpyridine sulfate, was at 0.1%.

3 parts by weight of the above polymer was dissolved in 100 parts by weight of water with stirring at room temperature to prepare a conductive composition. The solution thus obtained was applied onto a PET film by spin coating and dried at 120 ° C. A film having a smooth surface resistance value of 1.0 × 10 ⁵ Ω / □ having a film thickness of 1 μm was obtained.

Example 4 100 mmol of 2-aminophenol-4-sulfonic acid
Was dissolved in a 3 mol / l pyridine solution (N, N-dimethylformamide / water = 7/3; weight ratio) at 10 ° C., and a 100 mmol ammonium peroxodisulfate solution (N,
(N-dimethylformamide / water = 7/3; weight ratio) was added dropwise while cooling to −5 to 30 ° C. After completion of the dropping, the reaction product was filtered off after further stirring at 20 ° C. for 12 hours, washed with acetone and then dried to obtain about 20 g of a polymer powder. The volume resistance of this product is 12.0Ω ・
It was cm. In addition, 2-aminoanisole-4-sulfonic acid which is a residual monomer contained in this polymer is 1.0%, and methylpyridine sulfate which is a by-product salt is 1.0%.
%Met.

3 parts by weight of the above polymer was dissolved in 100 parts by weight of an isopropyl alcohol / water = 5/5 (weight ratio) solution at room temperature with stirring to prepare a conductive composition. The solution thus obtained was applied onto a quartz substrate by spin coating, and dried at 120 ° C. A film having a smooth surface resistance value of 4.0 × 10 ⁵ Ω / □ having a film thickness of 0.1 μm was obtained.

Example 5 2-Methyl-4-aminobenzenesulfonic acid 100 mm
was dissolved in a 4 mol / l trimethylamine solution (isopropylamine / water = 1/1; weight ratio) at 5 ° C., and a 100 mmol ammonium peroxodisulfate solution (isopropylamine / water = 1/1; weight ratio) was cooled. It was added dropwise so as to be 0 to 10 ° C. After dropping, 20 ℃
After further stirring for 12 hours, the polymerization solution was heated to 40 ° C. After heating, the mixture was further stirred at 40 ° C. for 2 hours, the reaction product was filtered off, washed with isopropyl alcohol and dried to obtain about 14 g of a polymer powder. The volume resistance value of this product was 10.0 Ω · cm. The residual monomer contained in this polymer was 2-methyl-4-aminobenzenesulfonic acid at 0.6%, and the by-product salt, trimethylamine sulfate, was at 0.5%.

3 parts by weight of the above polymer and water-soluble polyester resin "Alaster 300" [manufactured by Arakawa Chemical Industry Co., Ltd.] 1
100 parts by weight of water was stirred and dissolved in 100 parts by weight of water at room temperature to prepare a conductive composition. The solution thus obtained is treated with PE
It is applied on the T film by the dip coating method,
It was dried at ° C. A film having a film thickness of 1 μm and a smooth surface resistance value of 3.0 × 10 ⁵ Ω / □ was obtained.

Example 6 100 mmol of o-aminobenzenesulfonic acid was added at 25 ° C.
And dissolved in a 3 mol / l trimethylamine solution (DMSO / water = 3/7; weight ratio) with stirring, and a solution of 100 mmol of ammonium peroxodisulfate (DMSO / water = 3 /
7; weight ratio) was added dropwise while cooling to −5 to 30 ° C. After completion of the dropping, the mixture was further stirred at 20 ° C. for 12 hours, the reaction product was separated by a centrifugal filter and then dried to obtain 15 g of a polymer powder. The volume resistance value of this product was 20.0 Ωcm. The residual monomer contained in this polymer was 1.0% for o-aminobenzenesulfonic acid and 1.2% for the by-product salt trimethylamine sulfate.
It was 2%.

5 parts by weight of the above polymer was dissolved in 100 parts by weight of water with stirring at room temperature to prepare a conductive composition. The solution thus obtained was applied onto a PET film by a dip coating method and dried at 120 ° C. A film having a film thickness of 1 μm and a smooth surface resistance value of 8.0 × 10 ⁵ Ω / □ was obtained.

Comparative Example 1 2-Aminoanisole-4-sulfonic acid 100 mmol
Was dissolved in a 3 mol / l piperidine aqueous solution at 10 ° C.,
A 100 mmol aqueous solution of ammonium peroxodisulfate was added dropwise while cooling to 15 to 30 ° C. After completion of dropping, the reaction product was further stirred at 20 ° C. for 12 hours, washed with acetonitrile, and dried to give about 8 g of polymer powder.
Got The volume resistance value of this product was 55.0 Ω · cm. The residual monomer contained in this polymer was 2-aminoanisole-4-sulfonic acid at 5%, and the by-product salt, piperidine sulfate, was 9%.

3 parts by weight of the above polymer was dissolved in 100 parts by weight of water with stirring at room temperature to prepare a conductive composition. The solution thus obtained was applied onto a glass substrate by a spin coating method, but the coatability was poor and a uniform film could not be formed.

Comparative Example 2 100 mmol of o-aminobenzenesulfonic acid was added at 25 ° C.
Was dissolved with stirring in a 3 mol / l trimethylamine aqueous solution, and a solution of 100 mmol of ammonium peroxodisulfate (DMSO / water = 3/7; weight ratio) was added dropwise while cooling to −5 to 30 ° C. After dropping, 20
After further stirring for 12 hours at ℃, the reaction product was separated with a centrifugal filter and dried to obtain 7 g of polymer powder. The volume resistance value of this product was 150.0 Ωcm. The residual monomer contained in this polymer was 8.0% in o-aminobenzenesulfonic acid, and 11% in trimethylamine sulfate as a by-product salt.

5 parts by weight of the above polymer was dissolved in 100 parts by weight of water with stirring at room temperature to prepare a conductive composition. The solution thus obtained was applied onto a PET film by a dip coating method, but the coatability was poor and a uniform film could not be formed.

Comparative Example 3 2-Aminophenol-4-sulfonic acid 100 mmol
Was dissolved in a 3 mol / l triethylamine aqueous solution at 10 ° C., and a 100 mmol solution of ammonium peroxodisulfate was added dropwise while cooling to 5 to 20 ° C. After completion of dropping, the reaction product was further stirred at 20 ° C. for 12 hours, separated by a centrifugal filter, washed with acetonitrile, and then dried to obtain about 12 g of a polymer powder. The volume resistance value of this product was 35.0 Ω · cm. The residual monomer contained in the polymer was 2-aminophenol-4-sulfonic acid at 4%, and the by-product salt, piperidine sulfate, was at 5%.

3 parts by weight of the above polymer was dissolved in 100 parts by weight of water with stirring at room temperature to prepare a conductive composition. The solution thus obtained was applied onto a PET film by a dip coating method and dried at 150 ° C. A film having a film thickness of 1 μm and a smooth surface resistance value of 8.0 × 10 ⁶ Ω / □ was obtained. However, the obtained film was not smooth because crystals were precipitated on the surface.

[0087]

[Effect] According to the present invention, while exhibiting high conductivity, it has excellent solubility in alkaline, neutral (especially water), aqueous solutions having all pH values and organic solvents such as acetonitrile and alcohol. It was possible to provide a method for producing a highly pure soluble conductive polymer having excellent coatability and film strength.

[Brief description of drawings]

FIG. 1 is an IR chart of the polymer in Example 1.

FIG. 2 is an ion chromatography chart of residual monomer and residual by-product salt in the polymer in Example 1.

FIG. 3 is a chart of high performance liquid chromatography of the residual monomer and basic compound in the polymer in Example 1.

4 is a GPC chart of the polymer in Example 1. FIG.

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) C08G 73/00-73/26

Claims (9)

(57) [Claims] 1. A compound represented by the general formula (1): (In the formula, R ₁ , R ₂ , R ₃ , R ₄ and R ₅ are each hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms,
It is a group selected from the group consisting of a linear or branched alkoxy group having 1 to 4 carbon atoms, an acidic group, a hydroxyl group, a nitro group and halogen, and at least one of them is an acidic group. Further, the acidic group here means a sulfone group or a carboxyl group), at least one selected from the group consisting of an acidic group-substituted aniline, an alkali metal salt thereof, an alkaline earth metal salt, an ammonium salt and a substituted ammonium salt thereof. Compound (a) in a mixed solution of a basic compound (b) -containing aqueous solution and a water-soluble organic solvent (c) (only
Then, (b) / (c) = 3/7 to 7/3 (weight ratio)) , the polymerization is carried out with an oxidizing agent, and the following general formula (2): (In the formula, R ₂₁ , R ₂₂ , R _23, and R ₂₄ are each hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, or an acidic group. , A hydroxyl group, a nitro group, and a halogen, at least one of which is an acidic group, and the acidic group is a sulfone group or a carboxyl group). A method for producing a high-purity soluble aniline-based conductive polymer, characterized in that the weight average molecular weight thereof is 3,000 or more and the residual monomer content in the polymer is 3% by weight or less. 2. The structural formula of the soluble aniline-based conductive polymer is represented by the following general formula (3): (In the formula, R _{25 to} R ₄₀ are an electron withdrawing group, an acidic group, hydrogen, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a hydroxyl group, A group selected from the group consisting of a nitro group and a halogen, at least one of which represents an acidic group, and the acidic group represents a sulfone group or a carboxyl group) The method for producing a high-purity soluble aniline-based conductive polymer according to claim 1. 3. The method for producing a highly pure soluble aniline-based conductive polymer according to claim 1, wherein the basic compound (b) is an alkylamine having 1 to 3 carbon atoms and / or a heterocyclic amine. 4. The high-purity soluble organic solvent according to claim 1, 2 or 3, wherein the organic solvent (c) is at least one selected from the group consisting of alcohols, ketones, acetonitrile, dimethylformamide and dimethylsulfoxide. Method for producing aniline-based conductive polymer. 5. The method for producing a highly pure soluble aniline-based conductive polymer according to claim 1, 2, 3 or 4, wherein after the polymerization, the polymer is acid-treated with a solution (d) containing a protonic acid. 6. The method for producing a highly pure soluble aniline-based conductive polymer according to claim 1, wherein the oxidative polymerization is carried out at a temperature of 50 ° C. or lower. 7. After the polymerization, the polymer or the polymer after the acid treatment is washed with at least one solvent selected from methanol, ethanol, isopropyl alcohol, acetone, acetonitrile and N, N-dimethylformamide. A method for producing a highly pure soluble aniline-based conductive polymer as described in 1, 2, 3, 4, 5 or 6. 8. The polymer according to claim 1, 2, 3, 4, 5, 6 or 7, wherein after the polymerization, the polymer or the polymer after the acid treatment is isolated by using a separator utilizing centrifugal force. A method for producing a pure soluble aniline-based conductive polymer. 9. The method for producing a high-purity soluble aniline-based conductive polymer according to claim 8, wherein the temperature of the polymerization solution is 10 ° C. or lower when the polymer is isolated by using a separator utilizing centrifugal force.