JP2007126507A - Conductive composition and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conductive composition which is superior in conductivity and can be made into a film. <P>SOLUTION: The conductive composition which consists of a conjugated polymer (A) and a dopant (B), in which the dopant (B) is an organic polymer having a number-average molecular weight of 1,000-10,000, formed by reaction of a thiol compound and/or a disulfide compound with a compound containing a group having reactivity, with the conjugated polymer; and its manufacturing method, are provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a conductive composition, and more particularly to an amphiphilic conductive composition that has excellent conductive properties and can be formed into a film.

  Patent Document 1 discloses a method for producing a conductive polyaniline composition by mixing and dispersing polyaniline or a derivative thereof, a radical copolymer of a segment containing a group reactive with polyaniline and a monomer capable of radical polymerization. Is disclosed. However, as shown in Comparative Example 1 below, the resulting polyaniline composition uses a polymer dopant, but has a problem in conductivity. On the other hand, Patent Document 2 describes a method for producing conductive polyaniline that is stably dispersed in an organic solvent in a mixed phase including an aqueous phase and an organic phase.

JP 2002-265781 A PCT / JP2004 / 015203 application

  An object of the present invention is to provide an amphiphilic conductive composition that is obtained using a dopant that is amphiphilic in water and an organic solvent, and that can be made into a flexible and flexible film. is there.

According to the present invention, a conductive composition comprising (A) a conjugated polymer and (B) a dopant, wherein (B) the dopant is reactive with the thiol compound and / or disulfide compound, and the conjugated polymer. There is provided a conductive composition which is an organic polymer having a number average molecular weight of 1000 to 10,000 formed by a reaction with a compound containing a group having a number.
According to the present invention, in a mixed phase further including an aqueous phase and an organic phase, an organic polymer of a thiol compound and / or disulfide compound as a radical adduct and a compound containing a reactive group is used as a dopant. Provided is a method for producing a conductive composition that is stably dispersed in an organic solvent by oxidative polymerization of aniline and / or a derivative thereof in the presence of a molecular weight modifier and / or a phase transfer catalyst as necessary. .

  According to the present invention, a radical initiator includes a compound containing a thiol compound and / or a disulfide compound and a group reactive with a conjugated polymer (for example, a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, a sulfuric acid group, etc.). By reacting in the presence of, for example, a nitrogen atmosphere, an organic polymer useful as a dopant can be obtained, and this can be used as a dopant, for example, by conducting polymerization of aniline in toluene in a toluene / water system. A polyaniline-dispersed toluene solution in a state can be obtained. This solution can be made into a cast film, and a flexible film having a surface resistance value that is very low (as much as two orders of magnitude) compared to the conventional one can be obtained.

As a result of researches to solve the above problems, the present inventors have, for example, 2-acrylamido-2-methyl-1-propanesulfonic acid and 1-dodecanethiol in the presence of a radical initiator at 70 ° C. under nitrogen. Polymerization of aniline in toluene in a toluene / water system using Compound 1 obtained by reacting for 18 hours as a dopant yielded a doped polyaniline-dispersed toluene solution, which was casted into a film and its surface resistance value Was 2.76 × 10 ⁶ Ωsq, which was two orders of magnitude lower than that of a conventional copolymer of acrylamide sulfonic acid and alkyl acrylate. However, since it is a polymer dopant, a flexible film could be obtained. Thus, in the present invention, by synthesizing an amphipathic dopant, aniline can be polymerized in any of the aqueous organic solvent systems, and a conductive composition having excellent conductivity can be obtained. Since it is a molecular dopant, a flexible film can be obtained.

  Examples of the conjugated polymer used in the present invention include polyaniline, polythiophene polypyrrole, polyacetylene, polyparaphenylene, polyparaphenylene vinylene, polyfuran, polyselenophene, polyindole, polyazulene, and these are used alone or in any mixture. Can be used as Among these, aniline or a derivative thereof (for example, at least one alkyl group (preferably having 1 to 5 carbon atoms), alkenyl group or alkoxy group (preferably having 1 to 5 carbon atoms) at positions other than 4-position of aniline, Examples thereof include polyaniline derived from an alkylthio group, an alkoxyalkyl group (preferably having a carbon number of 1 to 5), an aryl group (preferably having a carbon number of 6 to 10), or any mixture thereof.

The thiol compound and / or disulfide compound used in the present invention is each represented by the formula R ¹ —SH, R ² —S—S—R ³ (wherein R ¹ , R ² and R ³ are each independently carbon A group that may contain a heteroatom of 3 to 30 (for example, a nitrogen atom, an oxygen atom, etc.), specifically, butyl mercaptan, octyl mercaptan, dodecyl mercaptan, hexadecyl mercaptan, tetradecyl mercaptan, 2, Thiol compounds such as 2,4,6,6-pentamethylheptane-4-methylenethiol, alkyl disulfides such as diethyl disulfide and dibutyl disulfide, aromatic disulfides such as diphenyl disulfide and dibenzyl disulfide, dimethylxanthogen disulfide, diethyl Keys such as xanthogen disulfide Examples thereof include disulfide compounds such as santhogen disulfides, tetramethylthiuram disulfide, thiuram disulfides such as tetraethylthiuram disulfide, etc. These are known compounds, many of which are generally commercially available. Examples of such reactions include addition, decomposition, and substitution reactions: When a growing polymer radical is present in the polymerization system, a substitution reaction is performed on the molecule, and when the generated radical starts a new polymerization, this is called chain transfer. In the present invention, the molecular weight of the dopant was controlled by using a thiol compound or a disulfide compound as a chain transfer agent.

  Examples of the compound containing a group having reactivity with the conjugated polymer used in the present invention include compounds containing a protonic acid group such as a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, and a sulfuric acid group. Specific examples include 2-acrylamido-2-methyl-1-propanesulfonic acid and 4-styrenesulfonic acid. Although there is no restriction | limiting in particular in the usage-amount of these compounds which have a proton acid group, It is preferable to use 2-200 mol with respect to 1 mol of thiol compounds and / or disulfide compounds preferably. These reactions can be performed using common radical initiators such as azo compounds such as azoisobutyronitrile (AIBN), 4,4′-azobis (cyanovaleric acid) (ACVA), and peroxides such as benzoyl peroxide (BPO). Although there is no limitation in the usage-amount, it is preferable that it is 0.01-0.5 mol with respect to 1 mol of monomers.

  As for the method for oxidative polymerization of aniline or a derivative thereof according to the present invention, a conventional method can be adopted except that the use of the reaction components is an essential requirement, and other general-purpose additives are also used in the present invention. As long as the purpose is not impaired, the conventional method can be adopted. The polymerization medium of the present invention uses two liquid media such as water and an organic solvent as a solvent. The organic solvent is not particularly limited as long as it dissolves aniline or a derivative thereof and is water-insoluble, and specific examples thereof include aromatic hydrocarbons such as benzene, toluene, xylene, etc .; hexane, heptane, octane Aliphatic hydrocarbons such as dichloroethane, chloroform, 1,2-dichloroethane, chlorobenzene, dichlorobenzene, etc .; diethyl ether, di-n-propyl ether, diisopropyl ether, di-n-butyl ether, tert -Ethers such as butyl methyl ether; esters such as ethyl acetate, n-propyl acetate, isopropyl acetate, and n-butyl acetate, among which aromatic hydrocarbons, aliphatic hydrocarbons and halogens are preferred. Hydrocarbons, particularly preferred are cheap and less toxic It is a circle and xylene. Two or more organic solvents may be mixed and used. The liquid medium may be used in any amount that can be stirred, and is usually used in an amount of 1 to 500 times by weight, preferably 2 to 300 times by weight, based on aniline or a derivative thereof. Here, the used amount of the organic solvent is 0.05 to 30 times by weight, preferably 0.1 to 10 times by weight with respect to water.

Although there is no restriction | limiting in particular in reaction temperature, Preferably it is -10-80 degreeC. Oxidized polymerized polyaniline according to the present invention has a very high yield, usually at least 80%, and its electric conductivity is 10 ^-9 Scm ^-1 or more.

  Examples of the additive that can be used in the oxidative polymerization of aniline or a derivative thereof according to the present invention include an oxidizing agent for oxidative polymerization of aniline that can be polymerized with the above aniline or a derivative thereof. Persulfates such as ammonium persulfate, persulfate, sodium persulfate, potassium persulfate, hydrogen peroxide, ferric chloride, ferric sulfate, potassium dichromate, potassium permanganate, hydrogen peroxide-ferrous A redox initiator such as a salt is preferably used. These oxidizing agents may be used alone or in combination of two or more. The amount of the oxidizing agent used is not particularly limited as long as it is an amount capable of oxidative polymerization of the aniline or derivative thereof, but is preferably 0.01 to 10 mol, more preferably 1 mol of aniline or derivative thereof. Is 0.1 to 5 mol.

  In the oxidative polymerization of aniline or derivatives thereof according to the present invention, molecular weight modifiers that can be used as necessary include aniline derivatives having a substituent at the 4-position, thiol compounds, disulfide compounds and / or α- A methyl styrene dimer etc. are mentioned, The usage-amount is although it does not specifically limit, Preferably it is 0.01-0.5 mol per mol of aniline or its derivative (s).

  The phase transfer catalyst that can be used in a preferred embodiment for oxidative polymerization of aniline or a derivative thereof according to the present invention is not particularly limited as long as it is generally used as a phase transfer catalyst. Specifically, benzyltriethyl Tetraalkylammonium halides such as ammonium chloride, methyltrioctylammonium chloride, tetra-n-butylammonium bromide, tetra-n-butylammonium iodide, tetra-n-butylammonium chloride; tetraalkylammonium such as tetrabutylammonium hydroxide Ammonium hydroxides; tetraalkylphosphonium halides such as methyltriphenylphosphonium bromide; 12-crown 4, 15-crown-5, 18 And crown ethers such as crown-6. Among them, tetraalkylammonium halides are preferable from the viewpoint of ease of handling such as removal of the catalyst after the reaction, and tetra-n-, which can be obtained industrially at low cost. Butyl ammonium bromide or tetra-n-butyl ammonium chloride is preferred. In the present invention, the amount of the phase transfer catalyst to be used is not particularly limited, if necessary, but is preferably 0.0001 mol times or more, more preferably 0.005 mol times or more, relative to the oxidizing agent. .

  In addition to the above-described components, the conductive composition according to the present invention includes polyethylene, polypropylene, polystyrene, polyethylene terephthalate, polyether sulfone, polyester, nylon, polyetherimide, polysulfone, polyetherketone, polyetheretherketone. , Thermoplastic resins such as acrylonitrile butadiene styrene copolymer, thermosetting resins such as epoxy, polyurethane, polyimide, acrylic resin, maleimide resin, silicone, photocurable resins such as oxetane, epoxy, vinyl ether, polyene, polythiol, acrylic resin Further, rubbers such as natural rubber, SBR, NBR, BR, IR, IIR and CR can be blended at an arbitrary ratio, and the conductivity of the insulator can be controlled. Furthermore, various additives that have been generally blended in conductive compositions such as carbon black, titanium oxide powder, metal fine particles such as gold, silver, and copper can be blended. It can be blended by a method, and the blending amount can be a conventional general blending amount as long as the object of the present invention is not violated.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further, it cannot be overemphasized that the scope of the present invention is not limited to these Examples.

Synthesis example 1
2-acrylamido-2-methyl-1-propanesulfonic acid (manufactured by Sigma-Aldrich Japan) 3 g (14.5 mmol) and 1-dodecanethiol (manufactured by Kanto Chemical Co., Ltd.) 0.293 g (1.45 mmol) In the presence of 0.203 g (0.724 mmol) of 4,4′-azobis (cyanovaleric acid) (ACVA) (manufactured by Wako Pure Chemical Industries, Ltd.) as a radical initiator, DMF (dimethylformamide) (Kanto) The compound 1 represented by the formula (I) was obtained by reacting in a nitrogen atmosphere at 30 ° C. for 18 hours in 30 g of Chemical Co., Ltd. and 15 g of toluene (Kanto Chemical Co., Ltd.). The number average molecular weight of Compound 1 was 2,100, and the ¹ H-NMR body was as follows.

¹ H-NMR: 0.83, 0.84, 0.86, 1.23, 1.28, 1.33, 1.38, 1.39, 1.43, 1.44, 1.46, ¹ .48, 1.50, 2.23, 2.44, 2.46, 2.55, 2.56, 2.59, 2.61, 2.62, 2.74, 2.79, 7.00 , 7.13, 7.26, 7.77, 8.04, 8.23 (chemical shift, ppm) (400 MHz, DMSO-d ₆ , 25 ° C.)

Synthesis example 2
2-acrylamido-2-methyl-1-propanesulfonic acid 3 g (14.5 mmol) and 1-dodecanethiol 0.146 g (0.724 mmol) in the presence of 0.203 g (0.724 mmol) of a radical initiator (ACVA), Reaction was performed in 30 g of DMF (dimethylformamide) and 15 g of toluene at 70 ° C. for 18 hours under a nitrogen atmosphere to obtain a compound 2 of the formula (II). The number average molecular weight of the compound 2 was 4,100, and the ¹ H-NMR value was as follows.

¹ H-NMR: 0.83, 0.84, 0.86, 1.23, 1.28, 1.33, 1.38, 1.39, 1.43, 1.44, 1.46, ¹ .48, 1.50, 2.23, 2.44, 2.46, 2.55, 2.56, 2.59, 2.61, 2.62, 2.74, 2.79, 7.00 , 7.13, 7.26, 7.77, 8.04, 8.23 (chemical shift, ppm) (400 MHz, DMSO-d ₆ , 25 ° C.)

Example 1
Polymerization of aniline was carried out in toluene / water toluene using Compound 1 obtained in Synthesis Example 1 as a dopant. That is, 1.0 g (10.7 mmol) of aniline (manufactured by Kanto Chemical Co., Ltd.) and 1.46 g (6.42 mmol) of compound 1 were dissolved in 50 g of toluene, and 6N hydrochloric acid (manufactured by Kanto Chemical Co., Ltd.) was dissolved therein. 25 g of distilled water in which 1.8 ml (10.7 mmol) was dissolved was added. To this mixed solution, 0.346 g (1.07 mmol) of tetrabutylammonium bromide (TBAB) (manufactured by Kanto Chemical Co., Inc.) was added, and the mixture was cooled to 0 ° C. and ammonium persulfate (APs) (manufactured by Kanto Chemical Co., Ltd.) 2 Distilled water (15 g) added with .70 g (11.8 mmol) was added, and the mixture was reacted at 0 ° C. for 15 hours with stirring at 250 rpm. A polyaniline-dispersed toluene solution in a dope state was obtained by separating and washing. When the surface resistance value of the cast film of the obtained toluene solution was measured in accordance with JIS K6991, it was 2.76 × 10 ⁶ Ω / sq.

Example 2
0.301 g of Compound 2 obtained in Synthesis Example 2 and 0.09 g of dedoped polyaniline (Emeraldine Base, Mn = 10,000) (manufactured by Sigma Aldrich Japan Co., Ltd.) and NMP (N-methyl-2) -Pyrrolidinone) (manufactured by Kanto Chemical Co., Inc.) 4.5 g was dispersed and mixed to obtain a polyaniline-dispersed NMP solution in a doped state. When the surface resistance value of the cast film of the obtained NMP solution was measured according to JIS K6991, it was 6.68 × 10 ⁶ Ω / sq.

Comparative Example 1
Stearyl acrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) 5 g (15.4 mmol) and 2-acrylamido-2-methyl-1-propanesulfonic acid 3.19 g (15.4 mmol) 0.216 g of radical initiator (ACVA) In the presence of (0.77 mmol), the reaction was carried out in a mixed solvent of 35 g of DMF and 10 g of toluene under a nitrogen atmosphere at 70 ° C. for 5 hours to obtain a compound 3 of the formula (III) having a number average molecular weight of 6,200.

¹ H-NMR: 0.89, 1.04, 1.22, 1.25, 1.51, 1.69, 1.81, 2.25, 2.77, 2.89, 2.97, 3 .92, 6.90, 8.03 (chemical shift, ppm) (400 MHz, CDCl ₃ , 25 ° C.)

Next, aniline in toluene was polymerized in a toluene / water system in the same manner as in Example 1 except that this compound 3 was used as a dopant. A polyaniline-dispersed toluene solution in a dope state was obtained by separating and washing. When the surface resistance value of the cast film of the obtained toluene solution was measured according to JIS K6991, it was 4.32 × 10 ⁸ Ω / sq.

Comparative Example 2
Aniline in toluene was polymerized in a toluene / water system in the same manner as in Example 1 except that dodecylbenzenesulfonic acid (DBSA) (manufactured by Kanto Chemical Co., Inc.) was used as a dopant. A polyaniline-dispersed toluene solution in a dope state was obtained by separating and washing. When the surface resistance value of the cast film of the obtained toluene solution was measured according to JIS K6991, it was 1.86 × 10 ⁶ Ω / sq.

As described above, according to the present invention, a radical polymer and / or reactant of a thiol compound and / or disulfide compound and a compound containing an acidic group is used as a dopant, and an organic solvent such as toluene / water system / For example, by forming a cast polyaniline-dispersed toluene solution obtained by polymerizing aniline in an aqueous system (in an organic solvent) into a cast film, it becomes 2.76 × 10 ⁶ Ωsq. In the conventional example, acrylamide sulfonic acid and alkyl The value is two orders of magnitude lower than that of a copolymer with acrylate, and a flexible film can be obtained. Therefore, the conductive composition of the present invention includes a semiconductive belt, a positive electrode material of a secondary battery, an electrochromic material, various sensor materials, an antistatic paint, an electromagnetic wave shielding material, an optical recording element, an artificial muscle material, an antirust material, It can be applied in a wide range of electrical, electronic and mechanical fields such as electrorheological fluid dispersants.

Claims (7)

  (A) A conductive composition comprising a conjugated polymer and (B) a dopant, wherein (B) the dopant comprises a thiol compound and / or a disulfide compound and a group reactive with the conjugated polymer. The electrically conductive composition which is an organic polymer with the number average molecular weights formed by reaction with 1000-10000. The conductive composition according to claim 1, wherein the thiol compound is represented by the formula: R ¹ —SH (wherein R ¹ is a group that may contain a heteroatom having 3 to 30 carbon atoms). The disulfide compound is represented by the formula: R ² —S—S—R ³ (wherein R ² and R ³ are each independently a group which may contain a heteroatom having 3 to 30 carbon atoms). 2. The conductive composition according to 1.   The conductive composition according to claim 1, wherein the conjugated polymer is polyaniline.   The conductive composition according to claim 1, wherein the group having reactivity with the conjugated polymer is a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, or a sulfuric acid group.   The conductive composition according to any one of claims 1 to 5, wherein the compound containing a group reactive with the conjugated polymer is (meth) acrylamide sulfonic acid and / or (meth) acrylamide carboxylic acid. .   In a mixed phase including an aqueous phase and an organic phase, an organic polymer of a thiol compound and / or disulfide compound as a radical adduct and a compound containing a reactive group is used as a dopant, and a molecular weight modifier as necessary. And / or a method of producing a conductive composition that is stably dispersed in an organic solvent by oxidative polymerization of aniline and / or a derivative thereof in the presence of a phase transfer catalyst.