JP3088525B2 - Polypyrrole derivative and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polypyrrole derivative which is soluble in an organic solvent and can form a flexible self-supporting film, and a method for producing the same.

[0002]

2. Description of the Related Art In recent years, conductive polymers have become new electronic materials,
For conductive materials, such as battery electrode materials, antistatic materials, electromagnetic wave shielding materials, photoelectric conversion elements, optical memories, functional elements such as various sensors, display elements, various hybrid materials, transparent conductors, various terminal equipment, etc. The application of is considered. However, polypyrrole generally has a highly developed π-conjugated system, so the main chain of the polymer is rigid, the interaction between the molecular chains is strong, and there are many strong hydrogen bonds between the molecular chains. It is insoluble in organic solvents and does not dissolve even by heating, so it has poor moldability and has a major drawback that casting and coating cannot be performed.

[0003] For this purpose, for example, a base material of a desired shape such as a fiber or a porous body of a polymer material is impregnated with a monomer, and the monomer is brought into contact with an appropriate polymerization catalyst, or
A similar composite material has been obtained by polymerizing by electrolytic oxidation to form a conductive composite material, or by polymerizing a monomer in the presence of a thermoplastic polymer powder. Further, those having a linear alkyl group or alkoxy group as a monomer (for example, 3-alkylpyrrole, 3-alkoxypyrrole, N-
It is possible to obtain a soluble polymer by using alkylpyrrole, but only a polymer having a low degree of polymerization and poor film-forming properties has been obtained. In addition, the conductivity during doping also tends to decrease, and there is a practical problem.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, and without impairing the original characteristics of polypyrrole,
An object of the present invention is to provide a polypyrrole derivative that is soluble in a general-purpose solvent and has processability such as coating.

[0005]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventor first prepared unsubstituted polypyrrole and then introduced a substituent such as an alkyl group at the N-position of polypyrrole. As a result, the inventors have found that the above problems can be solved, and have completed the present invention.

According to the present invention, poly (pyrrole-N-potassium) is obtained by reacting unsubstituted polypyrrole [the number of structural units n = 50-5000] with potassium metal, potassium alkoxide or potassium hydroxide. [RX: X represents chlorine, bromine or iodine, R represents an alkyl group or substituted alkyl group having 3 or more carbon atoms, an alkenyl group or substituted alkenyl group having 3 or more carbon atoms, an aryl group or substituted aryl group, or a benzyl group or substituted Represents a benzyl group. Wherein the following formula (I)

Embedded image And a structural unit represented by

Embedded image [In the formula, R represents an alkyl group or a substituted alkyl group having 3 or more carbon atoms, an alkenyl group or a substituted alkenyl group having 3 or more carbon atoms, an aryl group or a substituted aryl group, or a benzyl group or a substituted benzyl group. A polymer compound comprising the structural unit represented by the formula (I), wherein the sum of the number (m) of the structures represented by the formula (I) and the number (n) of the structures represented by the formula (II) is 50 to 5000, and n / M value is 0.0
This is a method for producing 1 to 100 polypyrrole derivatives.

[0007] The polypyrrole used in the present invention is produced by an oxidative coupling reaction of pyrrole. Also,
Polypyrrole can be produced by coupling 2,5-dihalogenated pyrrole with a catalyst such as nickel or without a catalyst. However, this method is not very common because the monomer used is unstable.

[0008] Specific polymerization methods of oxidative coupling include a method of polymerizing using an oxidizing agent catalyst and a method of electrochemically polymerizing. Among them, the method of polymerizing using an oxidizing agent catalyst is frequently used. This is preferable as a means for obtaining the union at low cost and easily. Examples of these polymerization catalysts include compounds known as Lewis acids such as aluminum chloride, iron chloride, molybdenum chloride, tungsten chloride, tin chloride, antimony chloride, and arsenic pentafluoride. Among these, those having no or weak oxidizing power, such as aluminum chloride, can be used in combination with an oxidizing agent such as cupric chloride, manganese dioxide, oxygen and the like.

The polypyrrole used in the present invention can be easily obtained at room temperature by adding these oxidizing agent catalysts to pyrrole under an atmosphere of an inert gas such as nitrogen or argon. Also, if necessary, an inert solvent such as chloroform, dichloromethane, tetrahydrofuran, ether or the like is added to the reaction system, which is a preferable method because the reaction can be easily controlled. Further, if necessary, the system can be heated.

The electrochemical oxidative polymerization is carried out in an electrolyte solution containing pyrrole at a potential of 0.1 to 30 V, at a constant current, a constant voltage, a constant potential, or the like under a low temperature, preferably -3.
Performed at 0-20 ° C. As a solvent constituting the electrolyte solution, organic solvents such as water, alcohol, ether, propylene carbonate, methylene chloride, nitrobenzene, nitromethane, acetonitrile, and benzonitrile, and a mixed solvent thereof are used. Examples of the electrolyte constituting the electrolyte solution include protonic acids such as hydrochloric acid, sulfuric acid, borofluoric acid, and perchloric acid, benzenesulfonic acid, p-toluenesulfonic acid, alkylsulfonic acid, alkylbenzenesulfonic acid, acetic acid, trifluoroacetic acid, and the like. Organic acids or salts thereof, lithium perchlorate, lithium tetrafluoroborate,
Electrolyte salts such as lithium hexafluoroarsenate, tetrabutylammonium tetrafluoroborate, and tetrabutylammonium perchlorate are used. Gold for electrodes,
In addition to a noble metal electrode such as platinum, a nickel electrode, a chromium electrode, and a carbon electrode, a glass electrode obtained by depositing stannic oxide or indium oxide on glass is preferable. Further, it is preferable that these electrochemical oxidation polymerizations are performed in an inert gas such as argon or nitrogen.

Since the polypyrrole powder or electrode film obtained by any of the above methods contains a dopant, it must be dedoped and then subjected to N-potassium reaction in the next step. Although there is no particular limitation on the de-doping treatment, it is thoroughly washed with water after being exposed to ammonia vapor, sufficiently washed with ammonia water, sufficiently washed with a solvent which dissolves the oxidizing agent catalyst well, and then exposed to ammonia vapor. It is possible to carry out reduction treatments in combination or to use them together.

The poly (pyrrole) thus obtained is brought into contact with potassium metal or reacted with potassium alkoxide to obtain poly (pyrrole-N-potassium) at room temperature.
Can be obtained. Also, together with potassium hydroxide, 4
It is also possible to obtain poly (pyrrole-N-potassium) by heating to 0 to 130 ° C. These reactions are also preferably performed in an inert gas. In addition, the reaction at this time can be performed in an inert halogen-based or ether-based solvent or in an alcohol.

The poly (pyrrole-N-potassium) thus obtained and a halide (RX: X and R have the above-mentioned meanings) are used directly or in an inert solvent at a low temperature, preferably at -20 to 10.degree. To introduce a substituent R at the N-position of polypyrrole.

Examples of the alkyl group having 3 or more carbon atoms for R include propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, hexadecyl, Linear alkyl groups such as docosyl groups, isobutyl groups, isopentyl groups,
A branched alkyl group such as a neopentyl group and an isohexyl group,
A cyclic alkyl group such as a cyclohexyl group, and one or more of those hydrogen atoms are a cyano group, a nitro group, a phenyl group,
Substitutes of the above-mentioned alkyl groups substituted with an alkoxy group or the like can be given.

Examples of the alkenyl group having 3 or more carbon atoms include an alkenyl group such as an allyl group, a butenyl group, a pentenyl group, and a hexenyl group, and one or more hydrogen atoms of which are a cyano group, a nitro group, a phenyl group, or an alkoxy group. And the like.

Examples of the aryl group include a phenyl group, a tolyl group, a 1-naphthyl group, a 2-naphthyl group and the like, and one or more hydrogen atoms thereof are a cyano group, a nitro group, a phenyl group,
The above-mentioned substituted aryl group substituted by an alkoxy group or the like can be mentioned. Examples of the substituent of the substituted benzyl group include a cyano group, a nitro group, a phenyl group and an alkoxy group. Specific examples of preferred halides include bromobutane, allyl bromide, p-bromonitrobenzene, benzyl chloride and the like.

In the present invention, the reaction for introducing a substituent into the N-position of polypyrrole is performed by
It is preferable to perform so that% is substituted. When the substitution at the N-position is less than 1%, sufficient solubility in an organic solvent cannot be obtained. The polypyrrole derivative produced by the present invention can be used in amide solvents such as N-methyl-2-pyrrolidone and N, N-dimethylacetamide, halogenated hydrocarbon solvents such as chloroform, dichloroethane and dichloromethane, and ether solvents such as tetrahydrofuran. It is soluble.

A good self-supporting film can be obtained by casting from a solution of a polypyrrole derivative dissolved in these solvents. The resulting film is made of a protic acid such as hydrochloric acid, sulfuric acid, borofluoric acid, or perchloric acid, an organic acid such as benzenesulfonic acid, p-toluenesulfonic acid, acetic acid or trifluoroacetic acid, iodine, bromine, chlorine, Halogen compounds such as iodine chloride, aluminum trichloride, iron trichloride, molybdenum chloride, tungsten chloride, antimony chloride, arsenic pentafluoride, Lewis acids such as sulfur trioxide, nitrosyl hexafluoroantimonate, nitrosyl hexafluoroarsenate, trifluoro oxidizing agents such as Russia methanesulfonic acid nitrosyl, 10 ^-3 to 10 by doping lithium, sodium, potassium, rubidium, an alkali metal such as cesium, tetraalkylammonium salts, etc.
^It shows a high conductivity of ³ S / cm.

The method of doping these dopants is not particularly limited. Generally, the dopant may be brought into contact with the polymer of the present invention, and the method is often performed in a gas phase or a liquid phase. Alternatively, lithium perchlorate, lithium tetrafluoroborate, lithium hexafluoroarsenate, tetrabutylammonium tetrafluoroborate,
A method of electrochemically doping with an electrolyte solution containing an electrolyte salt such as tetrabutylammonium perchlorate is also possible.

[0020]

【Example】

Example 1 Under a nitrogen gas stream, 24 g of anhydrous ferric chloride was placed in 300 ml of chloroform, and 3 g of pyrrole was added.
Stir for 20 hours. After the reaction mixture was added to 1 liter of methanol and stirred well, the solid substance was separated by filtration, washed thoroughly with methanol, water, methanol containing ammonia water and water in that order, and dried under reduced pressure to obtain 2.7 g of polypyrrole. Obtained. The degree of polymerization of this polymer was about 150 on average, as estimated from the degree of polymerization determined from the specific activity measurement of 2,5-ditritiated pyrrole synthesized under the same conditions [shown by the structural formula (I). 15 structural repeats
0].

This is dispersed in methanol, 1.14 g of potassium methoxide is added, and the mixture is stirred at room temperature for 5 hours. Further, 3 g of bromobutane was added thereto, and stirring was continued at room temperature for 24 hours. The solid was separated by filtration, washed sufficiently with methanol, water, methanol containing ammonia water and water in that order, and dried under reduced pressure to obtain 3.28 g of a polypyrrole derivative. The introduction of the butyl group was carried out at 2850-2950 cm ⁻¹
This was confirmed by the presence of an infrared absorption band caused by stretching. The ratio of the structure of Structural Formula (I) to the structure of Structural Formula (II) was found to be n / m ≒ 0.33 when determined from the intensity of the hydrogen of NH in proton NMR and the intensity of the hydrogen of methyl in the butyl group. Was.

This polymer is composed of N-methyl-2-pyrrolidone, N, N-dimethylacetamide, chloroform,
It showed good solubility in organic solvents such as dichloroethane, dichloromethane and tetrahydrofuran. Further, a free-standing film was obtained from a chloroform solution of this polymer by casting. The conductivity was 50 S / cm when iodine was doped.

Example 2 In Example 1, allyl bromide was used instead of bromobutane.
Using 5 g, the same treatment was carried out to obtain 4.97 g of a polypyrrole derivative. Allyl group introduction is 1645 cm
^-1 was confirmed by the presence of an infrared absorption band caused by C = C stretching of the allyl group. The ratio of the structure of Structural Formula (I) to the structure of Structural Formula (II) was found to be n / m ≒ 1 by proton NMR based on the strength of hydrogen of NH and the strength of hydrogen of methylene of the allyl group.

This polymer is composed of N-methyl-2-pyrrolidone, N, N-dimethylacetamide, chloroform,
It showed good solubility in organic solvents such as dichloroethane, dichloromethane and tetrahydrofuran. Further, a free-standing film was obtained from a chloroform solution of this polymer by casting. The conductivity was 40 S / cm when iodine was doped.

Example 3 The procedure of Example 1 was repeated except that 2.28 g of potassium methoxide and 6.0 g of benzyl chloride were used in place of bromobutane to obtain 3.67 g of a polypyrrole derivative. The introduction of the benzyl group was confirmed by the presence of an infrared absorption band at 2840 to 2980 cm ^-1 due to CH stretching of methylene of the benzyl group. The ratio of the structure of Structural Formula (I) to the structure of Structural Formula (II) was found to be n / m ≒ 49 by proton NMR from the strength of NH hydrogen and the strength of benzyl group methylene hydrogen.

This polymer is composed of N-methyl-2-pyrrolidone, N, N-dimethylacetamide, chloroform,
It showed good solubility in organic solvents such as dichloroethane, dichloromethane and tetrahydrofuran. Further, a free-standing film was obtained from a chloroform solution of this polymer by casting. The conductivity was 20 S / cm when iodine was doped.

Example 4 In a propylene carbonate solution containing 20 mmol of pyrrole and 10 mmol of tetraethylammonium tetrafluoroborate, a platinum plate was used as an electrode at a constant voltage of 1.5 V under an argon atmosphere until the quantity of electricity reached 1 C. The electropolymerization was performed at ℃. Since the polymer film grown on the platinum plate contains a dopant, the polymer film was dedoped by applying a potential of -0.1 V, further washed with aqueous ammonia and water, and dried under reduced pressure. The weight of the polymer peeled from the electrode was 0.1 g. The degree of polymerization of this polymer was about 250 on average, as estimated from the degree of polymerization determined from the specific activity measurement of 2,5-ditritiated pyrrole synthesized under the same conditions [shown by the structural formula (I). The number of repeating structures is 2
50].

In methanol, 0.1 g of potassium methoxide is added and stirred at room temperature for 10 hours. Further, 0.3 g of p-bromonitrobenzene was added thereto, and stirring was continued at room temperature for 48 hours. Wash the film thoroughly in the order of methanol, water, methanol containing ammonia water and water,
Drying under reduced pressure gave 0.15 g of a polypyrrole derivative.
The introduction of the nitrophenyl group was 1345 cm ^-1 and 1520
It was confirmed by the presence of an infrared absorption band at cm ^-1 due to a nitro group. The ratio of the structure of Structural Formula (I) to the structure of Structural Formula (II) was found to be n / m ≒ 0.2 when determined from the intensity ratio of the hydrogen of NH before and after the substitution reaction in proton NMR.

This polymer is composed of N-methyl-2-pyrrolidone, N, N-dimethylacetamide, chloroform,
It showed good solubility in organic solvents such as dichloroethane, dichloromethane and tetrahydrofuran. Further, a free-standing film was obtained from a chloroform solution of this polymer by casting. The conductivity was 50 S / cm when iodine was doped.

[0030]

The polypropylene obtained by the production method of the present invention
The roll derivative is soluble in various organic solvents, and can provide a cast, flexible, free-standing film,
Processing by a method such as coating is also possible, and these films and processed products can also exhibit high conductivity by doping. Therefore, electronic device materials as organic semiconductors, organic conductors, etc., as conductive materials,
Very useful for various applications.

Claims (1)

(57) [Claims] 1. An unsubstituted polypyrrole [the number of structural units n
= 50-5000] with potassium metal, potassium alkoxide or potassium hydroxide to give poly (pyrrole-N
-Potassium), and a halide [RX: X
Represents chlorine, bromine or iodine, R represents an alkyl group or a substituted alkyl group having 3 or more carbon atoms, an alkenyl group or a substituted alkenyl group having 3 or more carbon atoms, an aryl group or a substituted aryl group, or a benzyl group or a substituted benzyl group. . Wherein the following formula (I): And a structural unit represented by the following formula (II): [In the formula, R represents an alkyl group or a substituted alkyl group having 3 or more carbon atoms, an alkenyl group or a substituted alkenyl group having 3 or more carbon atoms, an aryl group or a substituted aryl group, or a benzyl group or a substituted benzyl group. A polymer compound comprising the structural unit represented by the formula (I), wherein the sum of the number (m) of the structures represented by the formula (I) and the number (n) of the structures represented by the formula (II) is 50 to 5000, and n / M value is 0.0
A method for producing a polypyrrole derivative of 1 to 100.