JP3149290B2 - Method for producing conductive polymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a novel conductive polymer which is extremely stable and has high solubility in water. More specifically, the present invention relates to electrodes, sensors, electronic display elements, non-linear optical elements, photoelectric conversion elements, antistatic agents, and other various conductive materials or optical materials that are highly demanded in terms of workability in the fields of electric and electronic industries. The present invention relates to a method for producing a novel water-soluble conductive polymer particularly suitable for use as a polymer.

[0002]

2. Description of the Related Art Polymers having a π-electron conjugated system have attracted industrial attention because of their unique physical properties such as a change in state at the metal / semiconductor transition, as well as conductivity, and have been studied for many uses. Have been. Among them, a water-soluble self-doped conjugated polymer obtained by covalently bonding a Bronsted acid group directly or indirectly via a spacer to a polymer main chain has a stable conductive property for a long time without the contribution of a foreign dopant. Particular attention has been paid to the status.

As a specific prior example, for example, F.S. Wud
l et al. E. FIG. Havinga et al., A polythiophene derivative having an alkanesulfonic acid group (Journal o
fAmerican Chemical Society
y, 109, 1858, 1987; Polyme
r Bulletin, 18: 277, 1987
), A polythiophene derivative or polypyrrole derivative of Aldissi (US Pat. No. 4,880,508), a polymer in which a carboxylic acid group is covalently bonded as a substituent to an aromatic ring of polyaniline (JP-A-1-500835), N-position of pyrrole Having a propane sulfonic acid group substituted therein (Journal of Chemical Soci
ety, Chemical Communication
n, 621, 1987), a polyaniline polymer having a propanesulfonic acid group substituted at the N-position (Journal)
of Chemical Society, Che
medical Communication, 180
Page, 1990; Synthetic Metals
Journal, Vol. 31, p. 369, 1989), a polyaniline derivative in which an aromatic ring is directly substituted with a sulfonic acid group (Journa).
l of American Chemical So
Citiy, 112, 2800, 1990) and the like have been disclosed together with the production method.

On the other hand, a bicyclic conductive polymer, for example, a polymer having an isothianaphthene structure is disclosed in Journal.
of Organic Chemistry, 49
Vol., P. 3382, 1984; and the like, and it is known that the energy gap (Eg) is extremely small at 1.1 eV and shows a stable conductive state. However, polyisothianaphthene is insoluble and infusible and has extremely poor moldability. Therefore, a method of introducing an alkyl group or an alkoxy group to make the compound soluble in an organic solvent is disclosed in Japanese Patent Application Laid-Open No. 242816/1990.

When an electron-withdrawing group or an electron-donating group is introduced into the isothianaphthenylene skeleton of the repeating structural unit,
Bred says that it affects the electronic state of a semiconductor
report the results of calculations (Journa
l of Chemical Physics, 85 (8), 4673, 1986). Further, as a related example, a polymer having a substituent as a halogen (Japanese Patent Application Laid-Open No.
307604) and Japanese Patent Publication (JP-A-2-252727) which enumerates a polymer having an electron-withdrawing group as a substituent, but none of the publications describes the properties of the polymer according to the present invention. There is no specific disclosure about the manufacturing method.

On the other hand, as a method for producing polyisothianaphthene from a polymer having a 1,3-dihydroisothianaphthenylene structure, a method using an electrochemical oxidative dehydrogenation reaction (JP-A-63-307604) ), An oxidative reaction by a gas phase reaction with sulfuryl chloride (Syntheti)
c Metals, 31 395 (1989)) and reaction with N-chlorosuccinimide (NCS) (Syn
thetic Metals, 47, 367, 199
2 years). In these prior arts, a molded product such as an insoluble and infusible polyisothianaphthene film is utilized by taking advantage of the fact that poly (1,3-dihydroisothianaphthenylene) is a polymer soluble in an organic solvent. A production method is described.

However, since the produced polyisothianaphthene is insoluble and infusible, there is a drawback that the processability is limited. In addition, since polyisothianaphthene is insoluble and infusible in a polymer reaction, even if a sulfonating agent such as fuming sulfuric acid is acted on, the reaction alone will not proceed sufficiently to the inside, and the water-soluble π electron conjugated No coalescence could be produced.

[0008]

DISCLOSURE OF THE INVENTION The present invention comprises a polymer containing a 1,3-dihydroisothianaphthenylene structure, which is reacted with a sulfonating agent to contain a sulfonic acid group-substituted isothianaphthenylene structure. It is intended to simply provide a water-soluble conductive polymer.

[0009]

That is, the present invention relates to [1] a compound represented by the following general formula (I):

Embedded image (Wherein R ¹ and R ² are each independently H, or a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms, a halogen, a nitro group, a primary, secondary or tertiary amino group. , A trihalomethyl group, a phenyl group, or a substituted phenyl group. The alkyl group or the alkoxy group represented by R ¹ or R ² may optionally include a carbonyl, ether, or amide bond.) By causing a sulfonating agent to act on the polymer, the following general formula (II)

Embedded image (Wherein R ¹ and R ² are the same as described above, and M represents H ⁺ or a cation such as an alkali metal ion such as Na ⁺ , Li ⁺ and K ⁺ or an ammonium ion or an alkyl-substituted quaternary ammonium ion). M: 0.2 to
2 range. (2) A method for producing a conductive polymer, which comprises producing a polymer having a chemical structure represented by the formula (2): [2] The method wherein a sulfonating agent is allowed to act on the polymer in the presence of an oxidizing agent. 1. A method for producing a conductive polymer according to item 1.

In the production method of the present invention, as described above, for example, a polymer having a known poly (1,3-dihydroisothianaphthenylene) structure is reacted with a sulfonating agent in the presence of a sulfonating agent or an oxidizing agent. Accordingly, it is an object of the present invention to provide a practical water-soluble conductive polymer. The production method using this sulfonating agent gives a water-soluble conductive polymer by causing a polymer having a π electron non-conjugated main chain to undergo two reactions, an oxidative dehydrogenation reaction and a sulfonation substitution reaction. This is a new manufacturing method.

As the polymer represented by the general formula (I), for example, poly (1,3-dihydroisothianaphthenylene) in which R ¹ = R ² = H is prepared by a known method, for example, A.I. J. Hee
It can be easily produced by the method described in JP-A-61-17581 by Ger et al.

The substituents R ¹ and R represented by the general formula (I)
² may be any substituent as long as it does not inhibit the sulfonation reaction and the oxidative dehydrogenation reaction. For example, each independently represents H, or a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms, halogen, , A nitro group, a primary, secondary or tertiary amino group substituted with an aliphatic or aromatic group, a trihalomethyl group such as trichloromethyl, a phenyl group, a substituted phenyl group and the like. The chain of the alkyl group or alkoxy group having 1 to 20 carbon atoms may contain a carbonyl, ether or amide bond.

Here, useful examples of R ¹ and R ² include hydrogen, an alkyl group, and an alkoxy group. Illustrating these substituents in more detail, alkyl groups include methyl, ethyl, isopropyl, butyl, pentyl, hexyl, octyl, dodecyl, methoxyethyl,
Examples of the alkoxy group such as ethoxyethyl, acetonyl and phenacyl include groups such as methoxy, ethoxy, propoxy, isopropoxy, octyloxy, dodecyloxy and the like.

Examples of substituents other than those described above for R ¹ and R ² include amino groups such as methylamino, ethylamino, diphenylamino, anilino, trifluoromethyl group, phenyl group, tosyl group, xylyl group, acetamide group and the like. Acylamide group and the like.

The precursor polymer having the chemical structure represented by the general formula (I) is a polymer having a molecular weight of 1,000 or more. By reacting the polymer represented by the general formula (I) with a sulfonating agent or depending on the type of the sulfonating agent, preferably in the presence of an oxidizing agent, the compound represented by the general formula (II)
A polymer having the chemical structure represented by is produced.

Specifically, when a polymer represented by the general formula (I) is used in combination with a sulfonating agent having an oxidizing ability or a sulfonating agent in combination with an oxidizing agent, the same reaction solution is used. A sulfonation substitution reaction and an oxidative dehydrogenation reaction take place therein, and a polymer having a chemical structure represented by the general formula (II) is obtained.

As the sulfonating agent used in this production method, sulfuric acid, fuming sulfuric acid, sulfur trioxide, chlorosulfuric acid, fluorosulfuric acid, amidosulfuric acid and the like can be generally mentioned, among which fuming sulfuric acid and sulfur trioxide are preferable. A plurality of these sulfonating agents may be mixed and used. The amount of the sulfonating agent to be used cannot be unconditionally determined because it varies depending on the type of the polymer having the chemical structure represented by the general formula (I) and the type of the sulfonating agent, but is generally included in the polymer. It is desirable to use the chemical structure represented by the general formula (I) in the range of 1.1 to 20 times the equivalent of 1 equivalent of the chemical structure.

The sulfonating agent can be used in combination with another oxidizing agent or oxidative dehydrogenating agent. These other oxidizing agents or oxidative dehydrogenating agents include, for example, ozone, peroxide, peracid, 2,3-dichloro-5,6
-Dicyano-1,4-benzoquinone, tetrachloro-
Quinones such as 1,2-benzoquinone, tetrachloro-1,4-benzoquinone and tetracyano-1,4-benzoquinone, halogens such as iodine and bromine, anhydrous aluminum chloride / cuprous chloride, anhydrous ferric chloride and Vanadium-based,
Manganese-based, oxygen oxidizing agents and the like using metal complex catalysts such as nickel-based and the like, and the like,
There is no particular limitation.

When these are used, lowering of the reaction temperature,
Since it is expected that the reaction time can be shortened and the yield can be improved, it is useful when a sulfonating agent having weak oxidizing power is used.
The concentration of the polymer having the chemical structure represented by the general formula (I) used in the present production method varies depending on the type of the polymer, the reaction scale or the type of other solvent, but is generally 1%.
A range of 0 ^{-2 to} 10 kg / liter is desirable.

The reaction temperature is determined according to each reaction method and is not particularly limited, but is generally in the range of -80 ° C to 250 ° C, particularly in the range of -30 ° C to 150 ° C. It is desirable to be performed in. The reaction time varies depending on the reaction method and the reaction temperature, the reaction pressure, the chemical structure of the polymer, and the like, and cannot be unconditionally specified.
Time is desirable. The reaction is preferably carried out at normal pressure, but can be carried out at a pressure of 10 ^-5 atm to 100 atm.

The sulfonation reaction and the oxidative dehydrogenation reaction must be a solution reaction dissolved using a sulfonating agent or a reaction solvent when the whole is sulfonated and oxidatively dehydrogenated. When preferable, the reaction can be performed in a gas phase, without a solvent, or in a poor solvent. If necessary, the reaction solvent used in the production method of the present invention varies depending on the reaction temperature and reaction time, the type of the sulfonating agent used, and the chemical structure of the polymer represented by the general formula (I). However, any solvent may be used as long as it dissolves the polymer and the sulfonating agent and does not inhibit the oxidative dehydrogenation reaction or the sulfonation substitution reaction.

For example, specifically, water, sulfuric acid, fuming sulfuric acid,
Polar solvents such as formic acid, acetic acid, propionic acid, acetic anhydride, or ethers such as tetrahydrofuran, dioxane, and diethyl ether; dimethylformamide, acetonitrile, benzonitrile, N-methylpyrrolidone (NMP), and dimethylsulfoxide (DMSO); And esters such as butyl acetate, and non-aromatic chlorine solvents such as chloroform and methylene chloride. Furthermore, these mixed solvents can also be used.

In order to suppress the formation of a known insoluble polymer having a sulfone bond (by-product) as a side reaction of the sulfonation reaction, a known sulfone inhibitor such as fatty acid, organic peracid, An acid anhydride, pyridine, acetic acid or ketone may be added in an amount of 0.01 to 50% by weight.

The general formula (I) obtained by the above production method
The polymer having the chemical structure represented by I) has high solubility in water, and can be isolated and purified by ultrafiltration, dialysis, and / or ion exchange operations. Further, when the polymer represented by the general formula (II) is obtained as a precipitate from the reaction solvent, the polymer can be isolated and purified by filtration, reprecipitation, and / or a solvent fractionation method.

The general formula (II) produced by the production method of the present invention
In the polymer containing the chemical structure represented by, m representing the substitution rate of the sulfonic acid group in the formula is in the range of 0.2 to 2,
Particularly, the range of 0.4 to 1.3 is preferable. M is H ⁺ , N
alkali metal ions such as a ⁺ , Li ⁺ , K ⁺ , and N
_{^{H 4 +, N (CH 3}} ) 4 +, N (C 6 H 5) 4 +, PH 4 +, P
(CH ₃ ) ₄ ⁺ , P (C ₆ H ₅ ) ₄ ⁺ , AsH ₄ ⁺ , As (C
An alkyl-substituted or aryl-substituted cation of a Vb group element such as H ₃ ) ₄ ⁺ and As (C ₆ H ₅ ) ₄ ⁺ is used.
Further, in order to convert to a specific cation, it can be converted to an arbitrary cation by performing ion exchange with a normal ion exchange resin.

In the formula of the polymer having the chemical structure represented by the general formula (II), when M is H ⁺ , the polymer exhibits a self-doping state in an aqueous solution without any extraneous dopant. By changing M, for example, the state may be indicated, the solubility in various solvents and the solvent affinity can be changed.

The water-soluble conductive polymer having a chemical structure represented by the general formula (II) of the present invention may be a known water-soluble conductive polymer, for example, a polythiophene derivative (JP-A-2-2428).
Compared with No. 16), the semiconductor has a feature that the energy gap as a semiconductor is as small as about 1.1 eV, shows high conductivity at a low doping level, and the conductive state can be obtained extremely stably. For this reason, the absorbance of visible light is reduced particularly during doping, so that it can be expected as a transparent conductor having excellent stability.

[0029]

According to the present invention, a novel water-soluble compound having a chemical structure represented by the general formula (II) is prepared by reacting a sulfonating agent on a bicyclic heterocyclic polymer represented by the general formula (I). Based on the fact that a conductive polymer was obtained, depending on the type of sulfonating agent, preferably simultaneously perform sulfonation substitution reaction and oxidative dehydrogenation reaction in the presence of another oxidative dehydrogenating agent It was obtained for the first time by a special reaction.

[0030]

The present invention will be described in more detail with reference to the following examples. However, the technical scope of the present invention is not limited by these examples. (Example 1) Method for producing polymer represented by general formula (II) <R ¹ = R ²
= H, M = Na ⁺ > At room temperature, 4 ml of fuming sulfuric acid (20% SO ₃ ) was added to 500 mg of poly (1,3-dihydroisothianaphthenylene) with stirring. Immediately, the reaction solution turned deep blue.
After stirring at room temperature for 3 days, the reaction mixture was added to 100 ml of 0.1 mL.
The mixture was poured into 1N NaOH / methanol, and the precipitated polymer was centrifuged. The polymer was dissolved in 100 ml of water, and sodium sulfate as an impurity was removed through a dialysis membrane. Water was distilled off from the aqueous solution, followed by vacuum drying to obtain 172 mg of a Na-type deep blue polymer (yield 34%). FIG. 1 shows the visible / near infrared spectrum of the obtained polymer. FIG. 2 shows the molecular weight distribution measured by GPC. FIG. 3 shows the infrared absorption spectrum. Elemental analysis _{(%) [C 8 H 3} S 2 O 3 Na] theory: C; 41.02%, H; 1.29%, S; 2
7.38%, Na; 9.82% Found: C; 41.47%, H; 1.41%, S; 2
7.81%, Na; 9.58%

(Example 2) Method for producing polymer represented by general formula (II) <R ¹ = R ²
= H, M = H ⁺ > 200 mg of reaction mixture produced in the same manner as in Example 1.
Was dissolved in about 500 ml of water, the pH was adjusted to 1.9 with hydrochloric acid, purified by ultrafiltration and concentrated, and the solvent was distilled off and dried in vacuo to obtain 150 mg of a black polymer. FIG. 4 shows a visible near-infrared spectrum of the obtained aqueous solution of the polymer. Next, when the pH was adjusted to around 8 by adding NaOH, the polymer in the solution returned to the visible / near infrared spectrum shown in FIG. As a result of measuring the electric conductivity of the polymer obtained by this production method by a four-terminal method, it was 1 S / cm.

(Example 3) Method for producing polymer represented by general formula (II) <R ¹ = R ²
= H, M = Li ⁺ > Black polymer 600 m produced in the same manner as in Example 2.
g was dissolved in 150 ml of water and subjected to an ion exchange treatment with a Li-type ion exchange resin (Amberlite IR-120B) to obtain an aqueous solution of a Li-type polymer. Evaporation of the water gave 605 mg of a deep blue polymer. The visible and near-infrared spectrum of the obtained polymer is equivalent to that obtained in Example 1, and the infrared absorption spectrum is shown in FIG. Elemental analysis _{(%) [C 8 H 3} S 2 O 3 Li] theory: C; 44.04%, H; 1.39%, S; 2
9.39%, Li; 3.18% Found: C; 44.59%, H; 1.62%, S; 2
8.96%, Li; 2.90%

(Example 4) Method for producing polymer represented by general formula (II) <R ¹ = R ²
= H, M = Na ⁺ > At room temperature, a solution of 500 mg of poly (1,3-dihydroisothianaphthenylene) in 1 ml of peracetic acid (New Experimental Chemistry Course, Vol. 17, Oxidation and Reduction, page I-2741) Prepared at 5 ° C. or below. Further, 2 ml of fuming sulfuric acid (20% SO ₃ ) was added with stirring while cooling to 5 ° C. or lower. Immediately, the reaction solution turned deep blue. After stirring for 1 day at room temperature, the reaction mixture was added to 100 ml of 0.1N
The mixture was poured into NaOH / methanol, and the precipitated polymer was centrifuged. The polymer was dissolved in 100 ml of water, and sodium sulfate as an impurity was removed through a dialysis membrane. Water is distilled off from the aqueous solution and dried under vacuum to obtain a dark blue polymer 19 of Na type.
5 mg were obtained. The visible near infrared spectrum and infrared absorption spectrum of the obtained polymer were the same as those obtained in Example 1.

Example 5 Method for producing polymer represented by general formula (II) <R ¹ = H,
R ² ＯO (CH ₂ ) ₉ CH ₃ , M = Na ⁺ > 5-decylisothianaphthene produced according to the method described in JP-A-2-242816 was obtained by using JP-A-61-1.
No. 7581, polymerized according to the method described in JP-A No. 7581, and 500 mg of the obtained poly (5-decyloxy-1,3-dihydroisothianaphthenylene) was stirred with fuming sulfuric acid (20%).
% SO ₃ ) was slowly added. Immediately, the reaction solution turned deep blue. The reaction mixture was added to 100 ml of 0.1 mL.
Sedimented in 5N NaOH / methanol and separated by centrifugation. After dissolving the solid in 100 ml of water and removing excess sodium sulfate by dialysis, the solvent was distilled off and vacuum dried to obtain 120 mg of a black polymer. The visible and near-infrared spectrum of the obtained polymer was similar to that obtained in Example 1.

(Example 6) Method for producing polymer represented by general formula (II) <R ¹ = R ²
= H, M = Na ⁺ > At room temperature, 4 ml of fuming sulfuric acid (containing 20% SO ₃ ) was added with stirring to a solution of 500 mg of poly (1,3-dihydroisothianaphthenylene) in 1 ml of glacial acetic acid. . Immediately, the reaction solution turned dark blue. After stirring at room temperature for 3 days, the reaction mixture was added to 100 ml of 0.1 N NaOH.
/ Methanol, and the precipitated polymer was centrifuged. The polymer was dissolved in 100 ml of water, and sodium sulfate as an impurity was removed through a dialysis membrane. Water was distilled off from the aqueous solution, followed by vacuum drying to obtain 201 mg of an Na-type deep blue polymer. The visible near infrared spectrum and infrared absorption spectrum of the obtained polymer were the same as those obtained in Example 1.

[0036]

The conductive polymer produced by the production method of the present invention is a water-soluble, high-processability conductive polymer, and therefore requires an electrode or sensor that requires precise processing. It is useful as various conductive materials or optical materials such as electronic display elements, nonlinear optical elements, optical conversion elements, and antistatic materials. Further, the feature of the production method according to the present invention is that it is particularly useful for producing a polymer having high conductivity under mild conditions using a precursor polymer excellent in processability and moldability as a raw material.

[Brief description of the drawings]

FIG. 1 is a visible and near-infrared spectrum of a polymer obtained in Example 1.

FIG. 2 is a gel permeation chromatograph of the polymer obtained in Example 1.

FIG. 3 is an infrared absorption spectrum of the polymer obtained in Example 1.

FIG. 4 is a visible and near-infrared spectrum of the polymer obtained in Example 2.

FIG. 5 is an infrared absorption spectrum of the polymer obtained in Example 3.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshiaki Ikenoue 2-24-25 Tamagawa, Ota-ku, Tokyo Showa Denko KK R & D Co., Ltd. (58) Field surveyed (Int. Cl. ⁷ , DB name) C08G 61/12 C09K 3/16 102 C09K 3/16 108 H01B 1/12

Claims (2)

(57) [Claims] 1. A compound of the general formula (I) (Wherein R ¹ and R ² are each independently H, or a linear or branched alkyl or alkoxy group having 1 to 20 carbon atoms, a halogen, a nitro group, a primary, secondary or tertiary amino group. , A trihalomethyl group, a phenyl group, or a substituted phenyl group. The alkyl group or the alkoxy group represented by R ¹ or R ² may optionally include a carbonyl, ether, or amide bond.) By reacting a sulfonating agent on the polymer, the following general formula (I
I) (Wherein R ¹ and R ² are the same as described above, and M represents H ⁺ or a cation such as an alkali metal ion such as Na ⁺ , Li ⁺ and K ⁺ or an ammonium ion or an alkyl-substituted quaternary ammonium ion). M: 0.2 to
2 range. A method for producing a conductive polymer, which comprises producing a polymer having the chemical structure represented by the formula (1). 2. The method for producing a conductive polymer according to claim 1, wherein the sulfonating agent is allowed to act on the polymer in the presence of an oxidizing agent.