JPH04293928A - Production of polyaniline derivative - Google Patents

Abstract

PURPOSE:To obtain the title derivative soluble in a general-purpose organic solvent without detriment to the properties inherent in polyaniline by introducing specified amino substituents into the nitrogen atoms of a reduced form polyaniline by reaction with a specified aziridine compound. CONSTITUTION:A polyaniline derivative is produced by introducing amino substituents of formula II (wherein R<1> and R<2> are each H, (substituted)alkyl, (substituted)alkenyl, (substituted)aryl or (substituted)benzyl) into the nitrogen atoms of a reduced form polyaniline by reaction with an aziridine compound of formula I. This derivative is soluble not only in N-methyl-2-pyrrolidone and N,N-dimethylacetamide but also in various solvents such as chloroform, tetrahydrofuran and ethanol, and the obtained solution can cause a good self-supporting film by casting.

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 polyaniline derivatives soluble in organic solvents.

0002

[Prior Art] In recent years, polyaniline has been used as a new electronic material and conductive material for battery electrode materials, antistatic materials, electromagnetic wave shielding materials, photoelectronic conversion elements, optical memories, functional elements such as various sensors, display elements, and various hybrids. material,
Applications to a wide range of fields such as transparent conductors and various terminal devices are being considered.

By the way, polyaniline generally has a highly developed π-conjugated system, so the main chain of the polymer is rigid, the interactions between the molecular chains are strong, and there are many strong hydrogen bonds between the molecular chains. Because of its presence, it is insoluble in most organic solvents and does not melt even when heated, so it has poor moldability and has the major drawback of not being able to be cast or coated. For this purpose, for example, fibers of polymeric materials,
By impregnating a base material of a desired shape such as a porous body with an aniline monomer and bringing this aniline monomer into contact with a suitable polymerization catalyst, or by polymerizing it by electrolytic oxidation, or alternatively, Similar composite materials have been obtained by polymerizing aniline monomers in the presence of thermoplastic polymer powders.

On the other hand, by modifying the polymerization catalyst and reaction temperature,
Polyaniline soluble only in N-methyl-2-pyrrolidone has also been synthesized (M. Abe et al.
:J. Chem. Soc. , Chem.
Commun. , 1989, 1736). However, this polyaniline is also hardly soluble in other general-purpose organic solvents, and its applicability is limited.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a polyaniline derivative that is soluble in general-purpose organic solvents without impairing the inherent properties of polyaniline.

[0006]

[Means for Solving the Problems] As a result of intensive studies aimed at solving the above problems, the present inventors have discovered that the above problems can be solved by introducing a substituent having a specific amino group to the nitrogen atom of polyaniline. They discovered this and completed the present invention.

The present invention relates to a method for producing a polyaniline derivative, and its structural feature is that reduced polyaniline has the following general formula (I) (wherein R1 and R2 may be the same or different). often represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted benzyl group, respectively).
By reacting the aziridine compound represented by the formula: -CHR1 CH(NH2
) R2 (wherein R1 and R2 have the same meanings as above) is to introduce a substituent having an amino group.

More specifically, the present invention involves treating aniline with ammonia to convert it into soluble polyaniline, then treating it with excess hydrazine to convert it into reduced polyaniline, and further dissolving it in an amide solvent. , or by dispersing the reduced polyaniline in an aromatic solvent or an ether solvent, adding an aziridine compound represented by the above general formula (I) to the resulting solution or dispersion, and reacting it with the nitrogen atom of the reduced polyaniline. , formula: -CHR1 CH(NH2
) R2 (wherein R1 and R2 have the same meanings as above) is characterized by introducing a substituent having an amino group.

The present invention will be explained in detail below. In the present invention, the number average molecular weight 2, which is obtained by oxidative polymerization of aniline at a low temperature, for example, at a temperature in the range of -20 to 50°C, using ammonium persulfate or the like as an oxidizing agent,
000 to 500,000 [measured by GCP (N-methyl-2-pyrrolidone solvent), number average molecular weight in terms of polystyrene] is used. First, this polyaniline is treated with ammonia to convert it into soluble polyaniline, and this soluble polyaniline is then treated with excess hydrazine to produce reduced polyaniline. Note that the term "reduced polyaniline" refers to a reduced form of polyaniline obtained by oxidative polymerization, in which a hydrogen atom is bonded to a nitrogen atom contained in polyaniline. In the treatment of hydrazine, soluble polyaniline is dispersed in water, hydrazine is added in an amount equivalent to or more, preferably 3 times or more, to the nitrogen atoms in polyaniline under a nitrogen atmosphere, and the mixture is heated for 24 hours.
This is done by stirring at 30°C.

The resulting reduced polyaniline is soluble in N-methyl-2-pyrrolidone or N,N-dimethylacetamide, but is almost insoluble in other general-purpose organic solvents such as chloroform and tetrahydrofuran.

Next, this reduced polyaniline is dissolved in an amide solvent or dispersed in an aromatic solvent or an ether solvent, and an aziridine compound represented by the above general formula (I) is added to the resulting solution or dispersion. was added and heated in a nitrogen atmosphere for several hours to two days to react, and the nitrogen atom of polyaniline was converted to the formula: -CHR1 CH(NH2
) R2 (wherein R1 and R2 have the same meanings as above) is introduced.

[0012] At that time, as the amide solvent, N-methyl-2-pyrrolidone, N,N-dimethylacetamide,
N,N-dimethylformamide, hexamethylphosphoric triamide, 1,3-dimethyl-2-imidazolidinone, etc. can be used. As the aromatic solvent, benzene, toluene, xylene, ethylbenzene, tetralin, etc. can be used. Further, as the ether solvent, ether, tetrahydrofuran, dioxane, etc. can be used.

In the present invention, R1 and R2 in the aziridine compound represented by the above general formula (I) may be the same or different, and each represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, It represents a substituted or unsubstituted aryl group or a substituted or unsubstituted benzyl group, and examples thereof include the following.

Examples of substituted or unsubstituted alkyl groups include ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, hexadecyl group, docosyl group, etc. Straight chain alkyl groups, isobutyl groups, isopentyl groups, neopentyl groups, branched chain alkyl groups such as isohexyl, cyclic alkyl groups such as cyclohexyl, and one or more of their hydrogen atoms are halogen atoms, cyano groups, nitro groups, Examples include those substituted with an alkoxy group, an ester group, or a hydroxyl group. Substituted or unsubstituted alkenyl groups include butenyl group, pentenyl group,
a hexenyl group, and one or more of their hydrogen atoms,
Examples include those substituted with a halogen atom, a cyano group, a nitro group, an alkoxy group, an ester group, or a hydroxyl group. The substituted or unsubstituted aryl group includes a phenyl group, and one or more hydrogen atoms of the phenyl group substituted with an alkyl group, a phenyl group, a halogen atom, a cyano group, a nitro group, an alkoxy group, an ester group, or a hydroxyl group. I can give what I have. Further, examples of the substituent in the substituted benzyl group include a halogen atom, a cyano group, a nitro group, an alkoxy group, an ester group, and a hydroxyl group.

[0015] Preferred aziridine compounds include:
Mention may be made of aziridine and 2-ethylaziridine.

In the present invention, it is preferable to carry out the reaction so that the above-mentioned substituent having an amino group is introduced into 10% or more of the nitrogen atoms of the reduced polyaniline. When the introduction rate is less than 10%, sufficient solubility in organic solvents cannot be obtained.

The polyaniline obtained as above, in which a substituent having the above amino group is introduced into the nitrogen atom, is
As a post-treatment, it is desirable to perform a dedoping treatment with aqueous ammonia.

[0018] The polyaniline produced by the present invention, in which the above-mentioned amino group-containing substituent is introduced into the above-mentioned nitrogen atom, is not only soluble in N-methyl-2-pyrrolidone and N,N-dimethylacetamide; Halogenated hydrocarbon solvents such as chloroform, dichloroethane, dichloromethane, ether solvents such as tetrahydrofuran,
It is soluble in alcoholic solvents such as methanol, ethanol, and propanol, and a film with good self-supporting properties can be obtained by cast molding using a solution dissolved in these solvents. In addition, the formed film can be obtained by doping it in a protic acid such as hydrochloric acid, sulfuric acid, fluoroboric acid, perchloric acid, etc.
It exhibits a high conductivity of −1 S/cm.

Furthermore, the polyaniline derivative produced according to the present invention can be exposed to several tens of ppm of acidic gas (in an undoped state).
Even when placed in an atmosphere containing (HCl, NO2), it is hardly doped. On the other hand, a thin film fully doped with protonic acid will not be dedoped even when immersed in neutral water. On the other hand, when conventional polyaniline is placed in an atmosphere containing several tens of ppm of acid gas (HCl, NO2), it is immediately doped and its conductivity changes significantly. Furthermore, when this thin film of polyaniline doped with protonic acid is immersed in neutral water, it is dedoped within a few minutes. This fact indicates that the polyaniline derivative according to the present invention has much higher environmental stability than conventional polyaniline.

[0020]

[Examples] The present invention will be explained below with reference to Examples. Example 1 Dissolve 4.1 g of aniline and 21.9 g of concentrated hydrochloric acid in water and make 1
00 ml and cooled to -5°C. 21.9g of concentrated hydrochloric acid,
Dissolve 6.28g of ammonium persulfate in water and add 100m
This solution was also cooled to -5°C, slowly added dropwise to the above aniline solution, and stirring was continued at -5°C for 4 hours. The number average molecular weight thus obtained was 12,000 (GP
The polyaniline (measured in C,N-methyl-2-pyrrolidone solvent, number average molecular weight in terms of polystyrene) was thoroughly washed with water, and then dedoped with aqueous ammonia. 200 m of soluble polyaniline thus obtained
1 of water, 50 ml of hydrazine was added under a nitrogen atmosphere, stirring was continued at room temperature for 24 hours, filtered and dried to obtain off-white reduced polyaniline.

1 g of the thus obtained reduced polyaniline
was completely dissolved in 30 ml of N-methyl-2-pyrrolidone, and the mixture was thoroughly purged with nitrogen. Then, 0.47 g of aziridine (100 mol% based on the nitrogen atom of the reduced polyaniline) was added and stirring was continued at 80°C for 12 hours. , reacted. This solution was poured into 1 liter of water with stirring, the precipitate was filtered off, dried, and dedoped with aqueous ammonia to obtain 1.2 g of a polyaniline derivative in which nitrogen atoms were substituted. The reaction yield revealed that the nitrogen atom substitution rate was 42%. The presence of primary amino groups was confirmed by the absorption at 3365 and 3290 cm −1 in the infrared absorption spectrum.

This polyaniline derivative has N-methyl-
It was not only soluble in 2-pyrrolidone, but also showed good solubility in organic solvents such as chloroform, dichloroethane, dichloromethane, and tetrahydrofuran. Furthermore, a self-supporting film could be obtained by cast molding from a chloroform solution of this polyaniline derivative. The conductivity was 0.01 S/cm when doped with sulfuric acid. Furthermore, the film before doping could be dissolved in the aforementioned organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, chloroform, dichloroethane, dichloromethane, tetrahydrofuran, and methanol.

When this dedoped film was left in air containing 10 ppm of HCl, the conductivity increased only from 10 -9 S/cm to 10 -8 S/cm after one hour. On the other hand, when a film doped with sulfuric acid is soaked in water, the conductivity changes from 0.01 S/cm to 1 S/cm after 1 hour.
It decreased only to 0-3 S/cm.

Example 2 1 g of the reduced polyaniline used in Example 1 was dispersed in 30 ml of benzene, and 0.47 g of aziridine was added to it.
g and 0.02 g of aluminum chloride for 12 hours at 80
Stirring was continued at ℃ to allow reaction. The precipitate was filtered, dried, and dedoped with aqueous ammonia to obtain 1.15 g of a polyaniline derivative in which nitrogen atoms were substituted. The reaction yield revealed that the nitrogen atom substitution rate was 32%. The presence of primary amino groups was confirmed by the absorption at 3365 and 3290 cm −1 in the infrared absorption spectrum.

This polyaniline derivative has N-methyl-
It was not only soluble in 2-pyrrolidone, but also showed good solubility in organic solvents such as chloroform, dichloroethane, dichloromethane, and tetrahydrofuran. Furthermore, a self-supporting film could be obtained by cast molding from a chloroform solution of this polyaniline derivative. The conductivity was 0.01 S/cm when doped with sulfuric acid. Furthermore, the film before doping could be dissolved in the aforementioned organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, chloroform, dichloroethane, dichloromethane, tetrahydrofuran, and methanol.

When this dedoped film was left in air containing 10 ppm of HCl, the conductivity increased only from 10 -9 S/cm to 10 -8 S/cm after one hour. On the other hand, when a film doped with sulfuric acid is soaked in water, the conductivity changes from 0.01 S/cm to 1 S/cm after 1 hour.
It decreased only to 0-3 S/cm.

Example 3 A polyaniline derivative in which 0.78 g of 2-ethylaziridine (100 mol % based on the nitrogen atom of reduced polyaniline) was used in place of aziridine in Example 1, and the nitrogen atom was substituted in the same manner as in Example 1. 1.2g of was obtained. The reaction yield revealed that the nitrogen atom substitution rate was 26%. The presence of primary amino groups indicates that 33% of the infrared absorption spectrum
Confirmed by absorption at 65 and 3290 cm-1.

This polyaniline derivative has N-methyl-
It was not only soluble in 2-pyrrolidone, but also showed good solubility in organic solvents such as chloroform, dichloroethane, dichloromethane, and tetrahydrofuran. Furthermore, a self-supporting film could be obtained by cast molding from a chloroform solution of this polyaniline derivative. The conductivity was 0.01 S/cm when doped with sulfuric acid. Furthermore, the film before doping could be dissolved in the aforementioned organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, chloroform, dichloroethane, dichloromethane, tetrahydrofuran, and methanol.

When this dedoped film was left in air containing 10 ppm of HCl, the conductivity increased only from 10 -9 S/cm to 10 -8 S/cm after one hour. On the other hand, when a film doped with sulfuric acid is soaked in water, the conductivity changes from 0.01 S/cm to 1 S/cm after 1 hour.
It decreased only to 0-3 S/cm.

Comparative Example: Dissolve 4.1 g of aniline and 21.9 g of concentrated hydrochloric acid in water.
00 ml and cooled to -5°C. 21.9g of concentrated hydrochloric acid,
Dissolve 6.28g of ammonium persulfate in water and add 100m
This solution was also cooled to -5°C, slowly added dropwise to the above aniline solution, and stirring was continued at -5°C for 4 hours. After thoroughly washing the polyaniline thus obtained with water, it was further subjected to dedoping treatment with aqueous ammonia. The polyaniline thus obtained was soluble in N-methyl-2-pyrrolidone, and a self-supporting film could be obtained from this solution. However, the polyaniline obtained was insoluble in chloroform and tetrahydrofuran, and the free-standing film obtained was insoluble in any organic solvent.

When this dedoped film was left in air containing 10 ppm of HCl, the electrical conductivity increased only from 10 -9 S/cm to 10 -3 S/cm in 5 minutes. On the other hand, when a film doped with sulfuric acid is soaked in water,
The conductivity dropped from 1 S/cm to 10-4 S/cm in 5 minutes.

[0032]

According to the present invention, by introducing a substituent having an amino group represented by the formula: -CHR1 CH(NH2)R2 into the nitrogen atom of reduced polyaniline, the original properties of polyaniline are not impaired. It is possible to produce a polyaniline derivative that is soluble in organic solvents and has excellent processability such as film formation and coating. The polyaniline derivative according to the present invention also has the advantage of being extremely environmentally stable.

Claims (3)

[Claims] [Claim 1] The following general formula (I
) (wherein R1 and R2 may be the same or different and each represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted benzyl group) ) is reacted with an aziridine compound represented by the formula: -CHR1 CH(NH
2) A method for producing a polyaniline derivative, which comprises introducing a substituent having an amino group represented by R2 (wherein R1 and R2 have the same meanings as above). 2. Polyaniline is treated with ammonia to convert it into soluble polyaniline, then treated with excess hydrazine to convert it into reduced polyaniline, and then dissolved in an amide solvent, or an aromatic solvent or an ether-based polyaniline. After dispersing in a solvent, the resulting solution or dispersion is mixed with the following general formula (I) (wherein R1 and R2 may be the same or different, and each represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or (represents an unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted benzyl group)
By adding and reacting an aziridine compound represented by the formula: -C to the nitrogen atom of the reduced polyaniline.
HR1 CH(NH2)R2 (wherein, R1 and R
2 has the same meaning as above. ) A method for producing a polyaniline derivative, which comprises introducing a substituent having an amino group represented by the following. [Claim 3] 10 nitrogen atoms of reduced polyaniline
% or more, a substituent having an amino group represented by the formula: -CHR1 CH(NH2)R2 (wherein R1 and R2 have the same meanings as above) is introduced. 2. The method for producing a polyaniline derivative according to 2.