JPH03220266A - Conductive polymer composition - Google Patents

Abstract

PURPOSE:To prepare the title compsn. being easily doped homogeneously with a dopant and giving a doped article from which the dopant can be easily removed by dispersing a solvent contg. a plasticizer capable of dissolving the dopant in a polymer having a long, pi electron-conjugated main chain. CONSTITUTION:The title compsn. is prepd. by dispersing a solvent 2 contg. a plasticizer capable of dissolving a dopant (e.g. a phthalic ester or a phosphoric ester) and a dopant 3 giving an electron conductivity (e.g. Cl<->, Br<->, or SO4<2-> as an electron acceptor, and Na<+> or K<+> as an electron donor) in a polymer 1 having a long, pi electron-conjugated main chain (e.g. polyacetylene or polypyrrole). The plasticizer penetrates into the gap between the polymer molecules 1, 1, converts strong bonds between the polymer molecules 1, 1 into weak bonds between the polymer and the plasticizer molecule, and acts as a lubricant between the polymer molecules 1, 1. The dopant 3 dissolves in the plasticizer layer formed between the polymer molecules 1, 1 and disperses homogeneously in the polymer. Since the polymer molecule 1 is covered with the plasticizer layer, the dopant can be easily removed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a π-electron conjugated conductive polymer composition.

Prior Art It is known that by doping a π-conjugated polymer with an electron-accepting compound or an electron-donating compound, the conductivity increases by eight orders of magnitude or more, and the conductivity of the semiconductor region is close to that of a metal region.

A typical example is polyacetylene doped with halogen (C, K).

Chang et al, Phys, Rev, L
ett, 39 (1977) 1098,).

Problems to be Solved by the Invention However, in conventional conductive polymer compositions, dopants are not uniformly doped, resulting in variations in conductivity, and dedoping when doped with dopants. The drawback is that it is difficult.

Means for Solving the Problems The conductive polymer composition of the first invention includes a polymer having a long π-electron conjugated main chain, a dopant that imparts electronic conductivity, and a dissolving material containing a dopant-soluble plasticizer. It is characterized by having a dispersed mobile dopant.

The conductive polymer composition of the second invention has a mobility property in which a dopant that imparts electronic conductivity and fine particles having a particle size of 10 to 11,000 nm are dispersed in a polymer having a long π-electron conjugated main chain. It is characterized by having a dopant.

According to the first aspect of the present invention, the plasticity of the polymer can be improved by dispersing a dissolving material containing a dopant-soluble plasticizer in the polymer having a long π-electron conjugated main chain.

As a result, the dopant is easily dispersed uniformly in the polymer through the plasticizer layer formed between the polymer chains. Furthermore, since the dopant is dissolved in the plasticizer layer, dedoping becomes easier.

According to the second invention, gaps can be formed between polymer chains by the fine particles. As a result, the dopant is easily dispersed uniformly in the polymer through the gap. It also becomes easier to dedope.

Example 1 As shown in FIG. 1, the conductive polymer composition of the first invention comprises a polymer having a π-electron conjugated main chain, a dissolving material 2 containing a dopant-soluble plasticizer, and a dopant imparting electronic conductivity. It has a structure in which 3 and 3 are dispersed. The plasticizer is polymer I, 1
When there is a crowd in between, the strong bond between polymer 1.1 becomes a bond between polymer 1 and plasticizer molecules, and therefore the strong bond is loosened, and the plasticizer acts as a lubricant between polymer 1.1. It does a good job. Since the dopant 3 is dissolved in the plasticizer layer formed between the polymers 1 and 1, it can be uniformly dispersed in the polymers. In addition, since the polymer 1 is surrounded by a plasticizer layer, when dedoped by electrochemical, chemical, or physical action, the dopant can be removed more easily than in conventional conductive polymer compositions. .

The polymer 1 is synthesized by chemical polymerization or electrolytic polymerization (anodic oxidation polymerization, cathodic oxidation polymerization), and specifically, polyacetylene, polythiophene, polypyrrole,
Polyphenylene sulfide, polyaniline, and their respective derivatives are used.

As the dissolving material 2, ordinary polymer plasticizers and high boiling point materials are effective, and among them, plasticizers such as phthalate esters, phosphate esters, and polyesters are particularly effective.

The dopant 3 is preferably one with a small ionic radius in consideration of mobility, and is preferably at least smaller than the SbF6- ion. Specifically, halogen (CI-1Br", Ia-), BFa
\Cl0n-1S04-1PFh-1AsF, \SbF
, - can be mentioned. Also, as an electron donor, sodium,
Examples include potassium and cesium.

As shown in FIG. 2, the conductive polymer composition of the second invention has a particle size of 10=1000 in a polymer having a π-electron conjugated main chain.
By dispersing fine particles 5 of 4.4 nm in diameter, the polymer 4.4
A gap is formed in between. As a result, the dopant 6 is easily dispersed uniformly in the polymer through the gap. Therefore, dedoping becomes easier.

Since the fine particles 5 serve as spacers between the polymers 4.4, their particle size is preferably about 10 to 11000 nm. 10nm
Below 11000 is too small to work as a spacer.
If it is more than n, it is too large and it is difficult to form a gap between the polymers 4.4.

Examples of the fine particles 5 include SiO□, TtO□, WO,
, ZnO1Fe304 and other metal oxides.

Hereinafter, specific examples 1 to 6 of the present invention and comparative examples 1 to 6 are as follows.
5 will be explained.

(Example 1) Nitrobenzene solution 30 containing 0.2 M of thiophene, 0.02 M of tetra-n-butylammonium perchlorate, and 0.2 M of di-2-ethylhexyl phthalate as a solubilizer.
0a+1 was placed in a glass container and kept at 5°C, using an ITO glass electrode (50 x 70 mm), 2 m47 cm"
Electrolytic oxidation polymerization was carried out for 20 minutes to obtain a polymer film doped with ClO4- ions on the anode.

After that, it was washed with methanol and dried in vacuum to a thickness of about 10 μm.
A polythiophene film was obtained. Ten pieces of this film were cut out for conductivity measurement, and one piece of film with a size of 20 x 20 mm was cut out for dedoping.

(Example 2) 1.8 ml of cumene under argon atmosphere, )so n-
Octyl aluminum 4.5ml (0.01mol)
, tetra-n-butyl titanate 1.7 ml (0
,005 mol) of the catalyst solution prepared by mixing 12
After heating at 0 °C for 2 h, the lnl was placed in a polymerization vessel;
Argon and cumene were removed from the container using a vacuum pump, and the catalyst solution was applied to the inner wall of the glass while rotating the polymerization container. After the pressure inside the polymerization vessel was reduced to 10-” Torr or less, the entire polymerization vessel was cooled to -78°C with a dry ice-ethanol mixed refrigerant, and acetylene gas was introduced into the polymerization vessel while maintaining this temperature. .The gas pressure at that time was approximately 600T.

The gas amount was adjusted so that rr. Simultaneously with the introduction of acetylene gas, polymerization occurred on the solution surface and the inner wall of the container, and formation of a polyacetylene film was observed. The reaction was continued for 4 hours, the acetylene gas was removed, and the inside of the polymerization vessel was returned to an argon atmosphere. The polyacetylene film was washed with toluene under an argon atmosphere. Washing was repeated until the color of the catalyst (blackish brown) was no longer attached to the solvent.

As a result, a polyacetylene film with a thickness of about 8 μm was obtained.

The resulting polyacetylene was cut into 50 x 50 mm pieces and immersed in di-2-ethylhexyl phthalate for 1 hour.

After washing di-2-ethylhexyl phthalate adhering to the film surface with toluene, it was dried in an argon atmosphere while spraying argon. This film was doped with iodine in the gas phase.

From this film, cut 10 sheets as conductivity measurement films of 2 x 2011 III+ size, 20 x 20
A piece of the dedoping film with a size of 1 mm was cut out.

(Example 3) Organic synthesis method (Synthetic Metals, 2
6 (1988) 267), poly(3-hexyl)thiophene was synthesized using 3-hexylthiophene.

1 g of the obtained poly(3-hexyl)thiophene and 0.5 g of the solubilizing agent propylene adipate were mixed in 100 g of chloroform.
It was dissolved in m1. A poly(3-hexyl)thiophene film with a thickness of about 10 μm was obtained by placing 5 ml of this solution in a Petri dish with a diameter of 8 cn+ and allowing chloroform to evaporate naturally.

This film was doped with iodine in the gas phase, and a film for conductivity measurement and a film for dedoping were cut out in the same manner as in Example 1.

(Example 4) 300 nl of a propylene carbonate solution containing 0.2 M of pyrrole, 0.02 M of tetra-n-butylammonium salt of hexafluoroantimony, and 0.2 M of tricresyl phosphate as a solubilizer was placed in a glass container and heated at 5°C. keep it to
2 m using ITO glass electrode (50 x 70 mm)
Electrolytic oxidation polymerization was carried out at 47cm" for 20 minutes, and BF,
- A polymer film doped with ions was obtained.

After that, it was washed with methanol and dried in vacuum to a thickness of about 10 μm.
A polypyrrole film was obtained. A film for conductivity measurement and a film for dedoping were cut out from this film in the same manner as in Example 1.

(Example 5) 0.02M Na2SO4 was added to a 0.2M pyrrole aqueous solution, 200 mg/1 Ti0z powder was suspended therein, and the mixture was allowed to stand still for electrolytic oxidation polymerization at 2 m 47 cm'' for 20 minutes.

TiO2 (average particle size: 1100 nm) manufactured by Aerosil was used. A polypyrrole film incorporating TiO□ with a thickness of about 12 μm was obtained on the anode.

A film for conductivity measurement and a film for dedoping were cut out from this film in the same manner as in Example 1.

(Example 6) Poly(3-hexyl)thiophene 1 obtained in Example 3
5i02 in 100ml of chloroform solution in which g is dissolved.
The powder (average particle size 1100 n) was suspended. A poly(3-hexyl)thiophene film with a thickness of about 12 μm was obtained by placing 5 ml of this solution in a Petri dish with a diameter of 80I11 and allowing chloroform to evaporate naturally.

This film was doped with iodine in the gas phase, and a film for conductivity measurement and a film for dedoping were cut out in the same manner as in Example 1.

(Comparative Example 1) In Example 1, thiophene was electrolytically oxidized and polymerized using a solution that did not contain the solubilizer di-2-ethylhexyl phthalate to obtain a polythiophene film.

A film for conductivity measurement and a film for dedoping were cut out from this film in the same manner as in Example 1.

(Comparative Example 2) The polyacetylene polymerized in Example 2 was treated with 2-
Doped with iodine without immersion in ethylhexyl.

A film for conductivity measurement and a film for dedoping were cut out from the obtained film in the same manner as in Example 1.

(Comparative Example 3) A dissolving agent propylene adipate was added to the poly(3-hexyl)thiophene synthesized in Example 3, and a film was made from the Jyoroform solution.

A film for conductivity measurement and a film for dedoping were cut out from the obtained film in the same manner as in Example 1.

(Comparative Example 4) In Example 4, polypyrrole was electrolytically oxidized and polymerized from a solution that did not contain the solubilizer tricresyl phosphate.

A film for conductivity measurement and a film for dedoping were cut out from the obtained film in the same manner as in Example 1.

(Comparative Example 5) In Example 5, polypyrrole was electrolytically oxidized and polymerized from a solution containing no TtO□ powder.

A film for conductivity measurement and a film for dedoping were cut out from the obtained film in the same manner as in Example 1.

Table 1 shows the results of measuring the electrical conductivity of the materials of Examples 1 to 6 and Comparative Examples 1 to 5 obtained as described above using the four-terminal method.

(Margin below) Table 1 (Conductivity: 37cm) As is clear from Table 1, the conductivity of Comparative Examples 1 to 5 had a variation of 50%, but the conductivity of Examples 1 to 6 It can be seen that the dopant is uniformly dispersed with a variation within 10%.

Next, the dedoping films of Examples 1 to 6 and Comparative Examples 1 to 5 were coated with 0.00% tetra-n-butylammonium perchlorate.
2 m in a propylene carbonate solution containing 02 M
The film was dedoped by electrolytic reduction at A/cm". The dedoped film was washed with methanol, dried in vacuum, and the dopant concentration was investigated by elemental analysis. Table 2 shows the results.

Table 2 Approximately 0.01 per unit of monomer even after dedoping
dopants were included, but in Examples 1 to 6, 0 dopants were included.
．． 001 or less, it can be seen that dedoping is likely to occur.

Effects of the Invention According to the present invention, it is possible to obtain a conductive polymer composition that is more easily doped with a dopant and more easily dedoped than conventional examples.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram showing an embodiment of the first invention, and FIG. 2 is a conceptual diagram showing an embodiment of the first invention.
1 is a conceptual diagram showing an embodiment of the invention.

Claims (5)

[Claims] (1) A conductive material having a mobile dopant obtained by dispersing a dopant that imparts electronic conductivity and a dissolving material containing a dopant-soluble plasticizer in a polymer having a long π-electron conjugated main chain. Polymer composition. (2) The plasticizer is a phthalate ester, a phosphate ester,
The conductive polymer composition according to claim 1, characterized in that it contains at least one of polyesters. (3) The conductive polymer composition according to claim 1, wherein the dopant is composed of ions having a smaller radius than the SbF_6^- ion. (4) A dopant that imparts electronic conductivity to a polymer with a long π-electron conjugated main chain, and a particle size of 10 to 1000 nm.
A conductive polymer composition comprising a mobile dopant in which fine particles are dispersed. (5) The conductive polymer composition according to claim 4, wherein the fine particles are metal oxides.