JP6785390B1 - Conductive polymer aqueous dispersion, conductive polymer coating film and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conductive polymer coating film of polythiophenes, polypyrroles, polyanilines, polyphenylene vinylenes, polyphenylenes and the like having improved moisture resistance. A conductive polymer aqueous dispersion comprising a vinyl alcohol-based polymer segment (A) and a styrene sulfonic acid-based polymer segment (B), including a block copolymer as a dispersant and dopant, and a conductive polymer. A method for producing a liquid, a conductive polymer coating, and a conductive polymer aqueous dispersion is used. [Selection diagram] None

Description

The present invention relates to an aqueous dispersion of a conductive polymer in which excess sulfonic acid is reduced, a conductive polymer coating film, and a method for producing the same.

Organic conductive polymers such as polythiophenes, polypyrroles, polyanilines, polyphenylene vinylenes, and polyphenylenes (hereinafter referred to as conductive polymers) are antistatic coatings from the viewpoints of conductivity, flexibility, light weight, and economy. , Solid electrolytic capacitor electrodes, electromagnetic wave shields, actuators, sensors, energy harvesting (power generation) materials, lithium secondary batteries, sodium secondary batteries, organic thin-film solar cells, dye-sensitized solar cells, organic EL displays, electronic paper , A member such as a touch panel, and is used or expected as a substitute for an ITO (indium tin oxide) transparent electrode.

However, since the above-mentioned conductive polymer is insoluble and insoluble and difficult to process such as coating, a type (so-called colloid) in which the conductive polymer is dispersed in an organic solvent or an aqueous solvent in the form of nanoparticles has been developed. It is already on the market. Among them, the aqueous colloid type in which VOC (volatile organic compound) is reduced as much as possible is the mainstream. In order to produce an aqueous colloid of a conductive polymer, a dispersant for colloidizing a water-insoluble conductive polymer into water is required, and the mainstream of the dispersant is polystyrene sulfonic acid (hereinafter referred to as PSS). ), Which is a strongly acidic polysulfonic acid compound, and the polysulfonic acid compound also functions as a dopand (see, for example, Patent Documents 1 and 2). For example, PSS acts like a template when oxidatively polymerizing 3,4-ethylenedioxythiophene (hereinafter referred to as EDOT), which is a typical raw material monomer for producing a conductive polymer, in water. To do. That is, EDOT is oxidatively polymerized along the PSS chain, and excess PSS or sulfonic acid in PSS that is not involved in doping functions as a dispersant, and colloidal stability is exhibited. The surplus PSS also functions as a binder when forming a coating film from the conductive polymer aqueous dispersion. In general, the longer the surplus PSS chain, the better the film-forming property due to the entanglement of the PSS chain and the like. That is, if the amount of PSS not involved in the doping is too small, the colloidal stability and film-forming property of the conductive polymer aqueous dispersion are lowered (see, for example, Non-Patent Document 1 and Non-Patent Document 2).

After forming a film from a conductive polymer aqueous dispersion, that is, after completely evaporating a dispersion medium such as water, it is involved in the excess PSS required to maintain colloidal stability or the doping in PSS. The sulfonic acid that is not used is unnecessary, but it is difficult to remove it by washing or the like because PSS strongly interacts with the conductive polymer. Since the excess PSS or sulfonic acid remaining in the coating film has strong acidity and hygroscopicity, the moisture resistance of the coating film, adhesion to the substrate and corrosiveness often become problems, and improvements thereof are strongly desired. ing.

Therefore, attempts have been made to reduce excess PSS. For example, the use of PSS-polydialkylacrylamide block copolymers instead of PSS (polystyrene sulfonic acid) has been proposed (eg, Non-Patent Document 3). It is a copolymer consisting of the minimum PSS block required for polymerization and doping of EDOT and the acrylamide block required for colloidal stability and film-forming property. However, in a strongly acidic dispersion, the acrylamide moiety is hydrolyzed and the purpose is There is a problem that the function is lost over time. Further, instead of suppressing the amount of PSS used, there is an attempt to add a vinyl alcohol-based polymer having a function as a dispersant and a binder in combination with PSS (for example, Patent Documents 3 and 4). However, since the vinyl alcohol polymer is basically not chemically bonded to the conductive polymer or PSS, the improvement of the colloidal stability and the film-forming property of the dispersion is insufficient, and there is a limit to the reduction of excess PSS. is there.

Further, a method has been proposed in which a free sulfonic acid is converted into a sulfonic acid ester by forming a film from an aqueous dispersion of a conductive polymer and then treating the film with an esterifying agent such as an orthoester (for example, Patent Documents). 5). However, the esterification rate is low, and there are problems such as the film peeling from the substrate in the treatment process.

Japanese Unexamined Patent Publication No. 7-90060 Japanese Unexamined Patent Publication No. 2004-59666 JP-A-2017-119778 Japanese Unexamined Patent Publication No. 2018-110073 Japanese Unexamined Patent Publication No. 2016-56334

Stephan Kirchmeyer et al., "Scientific importance, properties and growing applications of poly (3,4-ethylenedioxythiophene)" (3,4-ethylenedioxythiophene) ), Journal of Materials Chemistry, 2005, Vol. 15, pp. 2077-2088 F. F. Louwet et al., "PEDOT / PSS: synthesis, characterization, properties and applications" (PRDOT / PSS: synthesis, characterization, properties and applications), Synthetic Metals, 2003, 135-136, 115-117. Manabu Yamazaki et al., "Preparation of Conductive PEDOT Complex Using PSS-Polydialkylacrylamide Block Copolymer", Polymer Papers, 2017, Vol. 74, No. 6, pp. 524-533

The present invention has been made in view of the above problems, and an object thereof is polythiophenes, polypyrroles, polyanilines, polyphenylene vinylenes, polyphenylenes whose hygroscopicity and corrosiveness have been improved by reducing excess sulfonic acid. It is an object of the present invention to provide an aqueous dispersion of a conductive polymer such as, and a coating film.

As a result of diligent studies to solve the above problems, the present inventors have used a PSS-polyvinyl alcohol block instead of the conventional polystyrene sulfonic acid (hereinafter referred to as PSS) when producing a conductive polymer aqueous dispersion. We have found that by using a polymer (hereinafter referred to as PVA-PSS block copolymer) as a dispersant and dopant, sulfonic acid, which causes moisture absorption and corrosiveness of a conductive polymer coating film, can be reduced, and the present invention has been made. Has been completed.

That is, the present invention relates to a conductive polymer aqueous dispersion and a coating film in which excess sulfonic acid causing hygroscopicity and corrosiveness is reduced, and a method for producing the same, as shown below.
[1] A conductive polymer aqueous dispersion comprising a vinyl alcohol-based polymer segment (A) and a styrene sulfonic acid-based polymer segment (B), and containing a block copolymer as a dispersant and dopant and a conductive polymer. Related to.
[2] The degree of saponification of the vinyl alcohol-based polymer segment (A) is 70% or more, the number average molecular weight determined by gel permeation chromatography is 5,000 to 100,000, and the styrene sulfonic acid-based polymer segment (B) has a degree of saponification. The number average molecular weight determined by gel permeation chromatography is 5,000 to 100,000, and the weight ratio (A) / (B) of the vinyl alcohol-based polymer segment (A) to the styrene sulfonic acid-based polymer segment (B) is 10. The conductive polymer aqueous dispersion according to the above [1], which is / 90 to 90/10.
[3] The conductive polymer aqueous dispersion according to the above [1] or [2], wherein the conductive polymer is poly (3,4-ethylenedioxythiophene) or a derivative thereof.
[4] The aqueous dispersion of a conductive polymer according to any one of the above [1] to [3], wherein the weight ratio of the block copolymer to the conductive polymer is 50/100 to 3,000/100.
[5] The conductive polymer aqueous dispersion according to any one of the above [1] to [4] or the composition of the conductive polymer aqueous dispersion and the additive is applied onto the substrate and dried. The present invention relates to a conductive polymer coating film.
[6] The conductive polymer aqueous dispersion according to any one of the above [1] to [4] or the composition of the conductive polymer aqueous dispersion and the additive is applied onto the substrate and dried. The present invention relates to a method for producing a conductive polymer coating film.
[7] The method for producing an aqueous dispersion of a conductive polymer according to any one of the above [1] to [4], which comprises oxidatively polymerizing a monomer of a conductive polymer in an aqueous solvent containing a block copolymer. Related to.

The conductive polymer aqueous dispersion of the present invention is dispersion-stabilized by a block copolymer composed of a styrene sulfonic acid-based polymer segment and a vinyl alcohol-based polymer segment, instead of polysulfonic acid typified by conventional polystyrene sulfonic acid. , Excess sulfonic acid, which causes hygroscopicity and corrosiveness, which has been a conventional problem, has been reduced.
This is extremely useful in electrical material applications such as transparent electrodes, solid electrolytic capacitors, battery electrodes, and electromagnetic wave shielding materials.

Hereinafter, the present invention will be described in more detail.
According to the present invention, when producing an aqueous dispersion of a conductive polymer, a covalent bond is used as a dispersant and dopant to a styrene sulfonic acid-based polymer segment (B) (hereinafter referred to as PSS) instead of conventional polystyrene sulfonic acid. By using a so-called block copolymer (hereinafter referred to as PSS-PVA block copolymer) in which vinyl alcohol-based polymer segments (A) are linked, excess styrene that causes moisture absorption and corrosiveness is used. The present invention relates to an aqueous dispersion of a conductive polymer having reduced acids and a coating film thereof.

In the PSS-PVA block copolymer used for producing the conductive polymer aqueous dispersion of the present invention, the styrene sulfonic acid-based polymer segment (B) and the vinyl alcohol-based polymer segment (A) are blocked by a covalent bond. It is a concatenation. The PSS segment is involved in the polymerization of the conductive polymer, the colloidal stability of the dispersion, the dope and the film-forming property, like the conventional PSS, and the nonionic PVA segment is the colloidal stability and the structure of the aqueous dispersion of the conductive polymer. It is thought to be involved in membranous properties. Here, the styrene sulfonic acid-based polymer segment is not limited to the styrene sulfonic acid homopolymer, and includes a copolymer of styrene sulfonic acid or a styrene sulfonate and a copolymerizable monomer.

Examples of the copolymer include styrene sulfonic acid-styrene copolymer, styrene sulfonic acid-hydroxystyrene copolymer, styrene sulfonic acid-vinyl benzoic acid copolymer, styrene sulfonic acid- (meth) acrylamide copolymer, and the like. Sulfonic acid- (meth) acrylic acid copolymer, styrene sulfonic acid- (meth) acrylic acid ester copolymer, styrene sulfonic acid-N substituted maleimide copolymer, styrene sulfonic acid-maleic acid copolymer, styrene sulfon Examples thereof include acid-vinylpyridine copolymer, styrenesulfonic acid-diallyldimethylammonium copolymer, and styrenesulfonic acid-vinylsulfonic acid copolymer.
In the above-mentioned styrene sulfonic acid copolymer, the content of the styrene sulfonic acid unit is 60 mol% or more. If the content of the styrene sulfonic acid unit is less than 60 mol%, the degree of polymerization and the doping rate of the conductive polymer may be insufficient. More preferably, it is 80 mol% or more.

The vinyl alcohol-based polymer segment is not limited to a completely saponified product of polyvinyl acetate, and includes a partially saponified product and a saponified product of a vinyl acetate copolymer.
The vinyl acetate copolymer is not particularly limited as long as it is a copolymer of a monomer copolymerizable with vinyl acetate. For example, vinyl acetate-ethylene copolymer, vinyl acetate-acrylonitrile copolymer, vinyl acetate- Vinyl chloride copolymer, vinyl acetate-alkyl vinyl ether copolymer, vinyl acetate-vinylpyrrolidone copolymer, vinyl acetate-vinylacetamide copolymer, vinyl acetate-vinylformamide copolymer, vinyl acetate-vinylidene fluoride copolymer Examples thereof include coalescing, vinyl acetate-ethylene tetrafluoride copolymer, vinyl acetate-isobutylene copolymer, vinyl acetate- (meth) acrylic acid copolymer and the like.
The degree of saponification of polyvinyl acetate is preferably 70 mol% or more, more preferably 80 mol% or more, in consideration of the colloidal stability and film-forming property of the conductive polymer. On the other hand, if the degree of saponification exceeds 99.99 mol%, it may be difficult to produce PVA-SH, so 99.99 mol% or less is preferable.
In the vinyl acetate copolymer described above, the content of the vinyl acetate unit is 60 mol% or more. If the content of the vinyl acetate unit is less than 60 mol%, the colloidal stability and film-forming property of the conductive polymer aqueous dispersion may be insufficient. More preferably, it is 80 mol% or more.
As described above, vinyl acetate units are converted to vinyl alcohol units by saponification, but at present, polyvinyl alcohol cannot be directly produced by polymerization of vinyl alcohol.

PSS-PVA block copolymers and methods for producing them are known. For example, International Publication No. 2015/030084, JP-A-2016-28125, JP-A-59-189111, JP-A-3-174407, Terada et al., "Block copolymers containing polyvinyl alcohol as one component" Synthesis and its properties ”, Polymer Papers, 1992, Vol. 49, No. 11, pp. 885-891.
The PSS-PVA block copolymer used in the present invention can also be produced by these methods. For example, in International Publication No. 2015/030084, a block copolymer composed of a PSS segment and a PVA segment having a polyene structure is used as an ion exchange membrane. By introducing the dehydrated polyene structure, the reduction of high water content, which has been a problem of conventional ion exchange membranes, has been achieved. Further, although a conductive polymer material is mentioned as a possibility of using a PSS-PVA block copolymer having a dehydrated polyene structure, there is no specific description.

First, PVA having a mercapto group at the terminal (hereinafter referred to as PVA-SH) is synthesized, and in the presence of PVA-SH (acting as a chain transfer agent) and an oxidizing agent, styrene sulfonic acid (salt) alone or styrene sulfone This is a method of radically polymerizing a monomer that can be radically copolymerized with an acid (salt) and a styrene sulfonic acid (salt).

First, a method for producing PVA-SH will be described.
A monomer radically copolymerizable with vinyl esters such as vinyl acetate or vinyl esters such as vinyl acetate and vinyl esters such as vinyl acetate in the presence of thiolic acids such as thiol acetic acid, thiol propionic acid and thiol butyric acid. By polymerization, a polyvinyl ester-based polymer having a thioester group at one end (hereinafter referred to as thioester-terminal PVAc) can be produced, and this polymer can be saponified to produce PVA-SH.
At this time, since thiol acid has a high chain transfer reactivity, it is preferable to add thiol acid sequentially to the polymerization system at the initial stage of polymerization in order to increase the introduction rate of thioester to the PVAC terminal.
As the polymerization mode, any method such as bulk polymerization, solution polymerization, emulsion polymerization, and dispersion polymerization can be carried out, but solution polymerization is preferable in consideration of recovery and purity of the polymer.
The polymerization solvent is not particularly limited as long as it dissolves the monomer and the polymer, and examples thereof include hydrophilic solvents such as methanol, ethanol, acetone, and tetrahydrofuran.
Examples of the polymerization initiator include peroxides such as benzoyl peroxide, hydrogen peroxide, and t-butyl hydroperoxide, 2,2'-azobis (2,4-dimethylvaleronitrile), and 2,2'-azobis (2). -Methylpropionitrile), 2,2'-azobis (2-methylbutyronitrile) and other azo compounds can be used.

The number average molecular weight of PVA-SH may be in the range of 5,000 to 100,000, but 10,000 or more is more necessary to obtain sufficient colloidal stability and film-forming property of the aqueous dispersion of the conductive polymer. Preferably, 80,000 or less is more preferable in consideration of the PSS content in PVA-PSS and the viscosity of the conductive polymer aqueous dispersion.
For example, in the case of producing mercapto-terminal fully saponified polyvinyl alcohol having a number average molecular weight of 5,000 to 100,000 from thioester-terminated polyvinyl acetate, the preferable number average molecular weight before saponification is determined from the molecular weight ratio of the repeating units of both. The range is 9,800 to 195,000 (113 to 2,270 in terms of degree of polymerization).
The repeating unit of thioester-terminated polyvinyl acetate is 86.09 g / mol, and the repeating unit of mercapto-terminated fully saponified polyvinyl alcohol is 44.05 g / mol.
Further, the number average molecular weight and the weight average molecular weight indicating the molecular weight of the polymer may be measured by gel permeation chromatography (hereinafter, may be abbreviated as GPC) as described in Examples described later, and are equivalent thereto. It may be measured by the method of.

The thioester-terminated PVA is saponified in an alcohol solvent such as methanol at room temperature to 70 ° C., and the reaction time is usually 5 to 20 hours.
As the saponification catalyst, an alkaline catalyst such as sodium hydroxide, potassium hydroxide, or alkali metal alkoxide is used.

The above-mentioned PVA-SH can also be produced by a reversible addition cleavage transfer (RAFT) polymerization method. The RAFT polymerization method is a polymerization method using a RAFT agent such as dithioester, xanthate, dithiocarbamate, or trithiocarbonate as a chain transfer agent, and is widely known as one of living radical polymerization techniques. For example, Takahiro Inashige et al., "Polymer Design Using MADIX-Zantate Exchange Reaction", Polymer Proceedings, 2007, Vol. 64, No. 12, pp. 863-882, Hideharu Mori, "Functionality by RAFT Polymerization" "Precision Synthesis of Polymers", Polymer Papers, 2007, Vol. 64, No. 10, pp. 655-664).

In the presence of the RAFT agent, a monomer radically copolymerizable with vinyl esters such as vinyl acetate or vinyl esters such as vinyl acetate and vinyl esters such as vinyl acetate is radically polymerized to leave the RAFT agent at the polymer terminal. A polyvinyl ester-based polymer having a group (hereinafter referred to as RAFT-terminal PVAc) can be produced, and this polymer can be saponified to produce PVA-SH.
If a polyfunctional RAFT agent is used here, a polyfunctional RAFT-terminal PVAc can also be obtained.
The merit of the RAFT polymerization method is that the molecular weight distribution of PVA-SH can be narrowed and that a block copolymer can be produced. The RAFT polymerization method is basically the same as the above-mentioned production conditions for thioester-terminal PVCac. That is, the above-mentioned polymerization mode, polymerization solvent and polymerization initiator can be applied. The conditions for saponification of RAFT-terminal PVCac are the same as those for saponification of thioester-terminal PVCac described above.

Next, a method for producing PVA-PSS will be described.
In the solution of PVA-SH obtained above, styrene sulfonic acid (salt) alone or a monomer copolymerizable with styrene sulfonic acid (salt) and styrene sulfonic acid (salt) are dissolved to freeze degassing or inactivity. After sufficiently deoxidizing by gas bubbling or the like, a radical polymerization initiator such as an oxidizing agent, a peroxide, or an azo compound may be added for polymerization.

The polymerization solvent is not particularly limited as long as it dissolves a monomer such as PVA-SH and styrene sulfonic acid (salt), but water, water-alcohol mixed solvent, water-acetone mixed solvent, and water- tetrahydrofuran mixed solvent. , Dimethyl sulfoxide, dimethylformamide and the like.

The radical polymerization initiator is not particularly limited as long as it dissolves in the polymerization solution. For example, oxidizing agents such as potassium bromate, peroxides such as t-butyl hydroperoxide, hydrogen peroxide, potassium persulfate, sodium persulfate, ammonium persulfate, and 4,4'-azobis (4-cyanovaleric acid). ), 2,2'-Azobis {2-methyl-N- [1,1'-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2'-azobis {2- (2-imidazolin-) 2-Il) Propane] dihydrochloride, 2,2'-azobis {2- (2-imidazolin-2-yl) propane] disulfate dihydrate, 2,2'-azobis {2- [1- (2) -Hydroxyethyl) -2-imidazolin-2-yl) propane]} dihydrochloride, 2,2'-azobis (1-imino-1-pyrrolidino-2-methylpropane) dihydrochloride, 2,2'-azobis (2-Methylpropion amidine) dihydrochloride, 2,2'-azobis [N- (2-carboxyethyl) -2-methylpropion amidine] tetrahydrate, 1,1'-azobis (1-acetoxy-1-) Examples thereof include azo initiators such as phenylmethane), 4,4'-diazendiylbis (4-cyanopentanoic acid) and α-hydro-ω-hydroxypoly (oxyethylene).

The polymerization temperature is room temperature to 95 ° C., and the polymerization time is usually 2 to 30 hours.
The number average molecular weight required for GPC in the PSS segment is 5,000 to 100,000, but considering the colloidal stability, film-forming property, and conductivity of the coating film of the conductive polymer aqueous dispersion, 10,000. The above is preferable, and 80,000 or less is preferable in consideration of the viscosity of the dispersion liquid.
The composition of the PVA-PSS block copolymer, that is, the weight ratio of the vinyl alcohol-based polymer segment to the styrene sulfonic acid-based polymer segment may be in the range of 10/90 to 90/10. When the content of the PVA segment is less than 10 wt%, the effect of reducing the excess sulfonic acid by the PVA segment may not be sufficiently exhibited. Further, when the content of the PVA segment is more than 90 wt%, the polymerizable property (degree of polymerization and doping rate) of the conductive polymer may decrease. Therefore, the weight ratio is preferably in the range of 30/70 to 70/30.

Since the PVA-PSS obtained above contains many impurities, metal cations and impurities contained in the polymerization initiator, the monomer residue, and the styrene sulfonic acid (salt) are used by using an ion exchange resin, an ultrafiltration membrane, or the like. Should be removed.
In addition to the above, as a method for producing a PVAc-PSS block copolymer which is a precursor of PVA-PSS, a so-called living polymerization method in which a vinyl acetate-based monomer is polymerized and then a styrene sulfonic acid-based monomer is polymerized is also used. is there.
Since the PVA segment of the PVA-PSS block copolymer used in the present invention has a role of imparting colloidal stability and film-forming property of the conductive polymer aqueous dispersion, it is preferable that the PVA segment does not have a dehydrated vinylene structure.

Next, a method for producing the conductive polymer aqueous dispersion of the present invention will be described.
First, a method for producing an aqueous dispersion of a conductive polymer using polythiophenes, polypyrroles, polyanilines, polyphenylene vinylenes, polyphenylenes and the like as conductive polymers will be described.
These production methods are not particularly limited, and known methods can be applied. For example, patent documents such as JP-A-7-96066, JP-A-2004-59666, JP-A-2010-40770, JP-A-2011-102376, and Polymers 2011, Vol. 52, pp. 1375-1384. , Polymer Review 2010, Vol. 50, pp. 340-384, etc.

In the method for producing the conductive polymer aqueous dispersion of the present invention, the conductive polymer monomer is emulsified and dispersed in an aqueous solvent containing PVA-PSS of the present invention as a dispersant and dopant, and an oxidizing agent is added for oxidative polymerization. By doing so, a method of producing an aqueous dispersion of a conductive polymer (also referred to as an aqueous colloid) in which the nanoparticles of the conductive polymer are dispersed and stabilized in an aqueous medium can be mentioned. At this time, a conventional sulfonic acid compound such as PSS or dodecylbenzene sulfonic acid may be used in combination in order to promote the emulsification of the monomer.

Examples of the above-mentioned conductive polymer monomer include thiophenes such as thiophene, 3,4-ethylenedioxythiophene, 3-alkylthiophene, and 3-alkoxythiophene, pyrrole, 3-alkylpyrrole, 3,4-dialkylpyrrole, and 3. -Pyrroles such as alkoxypyrrole and 3,4-dialkoxypyrrole, aniline such as aniline, 2-alkylaniline and 2-alkoxypyrrole, phenylene vinylene and the like can be mentioned.
The above-mentioned aqueous solvent (aqueous medium) may be water such as purified water, but may be a mixed solvent in which water and a water-soluble solvent are mixed.
Water-soluble solvents include acetone, methanol, ethanol, propanol, butanol, ethoxyethanol, methoxyethanol, glycerin, propylene glycol, ethylene glycol, butanediol, acetic acid, propionic acid, N, N-dimethylformamide, dimethyl sulfoxide, acetonitrile and the like. Can be mentioned.

The amount of PVA-PSS used is 50 parts by weight to 3,000 parts by weight with respect to 100 parts by weight of the monomer giving the conductive polymer. Considering the colloidal stability and particle size of the conductive polymer aqueous dispersion, 100 parts by weight or more is preferable, and considering the conductivity of the conductive polymer coating film, 500 parts by weight or less is more preferable.

Oxidizing agents used include persulfates such as persulfate, potassium persulfate, ammonium persulfate, and sodium persulfate, iron benzenesulfonate (III), iron p-toluenesulfonate (III), and iron dodecylbenzenesulfonate. Organic iron (III), iron (III) chloride, iron (III) nitrate, iron (III) sulfate, ammonium iron sulfate (III), iron perchlorate (III), iron tetrafluoroborate (III), etc. Examples include inorganic iron (III) sulfate and oxygen.
The amount of the above-mentioned oxidizing agent used is 1 equivalent to 10 equivalents per mole of the monomer giving the conductive polymer. Considering the polymerization rate, 2 equivalents or more is preferable, and considering the conductivity of the conductive polymer coating film, 5 equivalents or less is more preferable.

The total concentration of PVA-PSS and the monomer giving the conductive polymer in the above-mentioned aqueous medium is 0.1% by weight to 20% by weight in total, and the colloidal stability, viscosity, and polymerization of the aqueous dispersion of the conductive polymer. Considering the speed and the conductivity of the conductive polymer coating, 0.5% by weight to 10% by weight is more preferable.
The temperature of the oxidative polymerization is 0 ° C to 100 ° C, and 0 ° C to 30 ° C is more preferable from the viewpoint of suppressing side reactions. The polymerization time depends on the type and amount of the oxidizing agent used, the polymerization temperature, and the pH, but is usually 10 hours to 72 hours.

In the above-mentioned oxidative polymerization, the PVA-PSS, the monomer giving the conductive polymer, and the oxidizing agent may be collectively charged into the reactor at the start of the polymerization, but each drug may be divided or continuously added. Further, in order to increase the colloidal stability of the aqueous dispersion of the conductive polymer and reduce the particle size of the conductive polymer, oxidative polymerization may be carried out while irradiating with ultrasonic waves.

The production of an aqueous dispersion containing, for example, poly (3,4-ethylenedioxythiophene) (hereinafter referred to as PEDOT) and PVA-PSS as the conductive polymer aqueous dispersion of the present invention will be described in detail.
First, an aqueous solution of PVA-PSS is charged into a reactor, 3,4-ethylenedioxythiophene is added, and the mixture is stirred and emulsified at 0 ° C to 30 ° C. At this time, emulsification may be promoted by irradiating ultrasonic waves or adding a surfactant such as dodecylbenzenesulfonic acid.
The amount of PVA-PSS used is 50 parts by weight to 3,000 parts by weight with respect to 100 parts by weight of 3,4-ethylenedioxythiophene. To this, an oxidizing agent such as ammonium persulfate in an amount of 1 to 10 equivalents is added to 3,4-ethylenedioxythiophene, and oxidative polymerization is carried out at 0 ° C. to 30 ° C. for 10 hours to 72 hours.
After oxidative polymerization, unnecessary cations and anionic impurities such as metal cations, ammonium cations, sulfate anions, and halogen anions are removed by methods such as cation exchange resin, anion exchange resin, chelate resin, ultrafiltration, and / or dialysis. And purify.

In the production of the above-mentioned PEDOT aqueous dispersion, the larger the amount of PVA-PSS added to 3,4-ethylenedioxythiophene, the smaller the particle size of the conductive polymer. For example, it is possible to obtain a nano-level dispersion having an average particle size of 10 nm to 30 nm, which has an advantage of improving the permeability to a porous substrate. Of course, not only the amount of PVA-PSS added, but also the composition and molecular weight of PVA-PSS change the particle size and physical properties of the coating film of the conductive polymer. On the other hand, if the amount of PVA-PSS used is insufficient, the degree of polymerization of the conductive polymer does not increase, the colloidal stability decreases, and the particle size increases, resulting in a decrease in the density of the conductive polymer coating film. , The conductivity may decrease. Therefore, the amount of PVA-PSS used is preferably 100 to 500 polymerized parts.

Further, although the PVA-PSS of the present invention functions as a dispersant and a dopant, other dopants may be used in combination, for example, methanesulfonic acid, benzenesulfonic acid, paratoluenesulfonic acid, naphthalenesulfonic acid, 2-naphthalene. Sulfonic acid, 10-campar sulfonic acid, 4-hydroxybenzene sulfonic acid, nitrobenzene sulfonic acid, cypress sulfonic acid, 2-anthraquinone sulfonic acid, 1,5-anthraquinone disulfonic acid, 2,6-anthraquinone disulfonic acid, poly (2-) Acrylamide-2-propanesulfonic acid), lignin sulfonic acid, phenolsulfonic acid novolac resin, sulfonated polyester, polyvinylsulfonic acid, polyisoprenesulfonic acid, polymetallyloxybenzenesulfonic acid, bis (trifluoromethanesulfonyl) imide acid, bis (Perfluoroalkanesulfonyl) Sulfonic acid compounds such as imide, methanesulfonic acid polyacrylate, polyacrylic acid, polymethacrylic acid, polyaspartic acid, polymaleic acid, polyvinyl benzoic acid, acetic acid, maleic acid, carboxyphenol, phthalic acid Examples thereof include carboxylic acid compounds such as aldehyde, carboxyphenol, carboxycresol, carboxynaphthalene and dicarboxynaphthalene, and polyphosphoric acid.

Dimethyl sulfoxide, ethylene glycol, diethylene glycol, glycerin, γ-butyrolactone, as secondary dopants, in order to promote the rearrangement of the conductive polymer chains and improve the conductivity in the conductive polymer aqueous dispersion produced above. Sulfolane, N-methylpyrrolidone, dimethylsulfone, and sugar alcohols such as erythritol, pentaerythritol, and sorbitol may be added.
An aqueous solution or dispersion of another polymer may be added to the aqueous dispersion of the conductive polymer produced above for the purpose of improving the adhesion of the conductive polymer coating film to various substrates and the mechanical properties. For example, polyester resin, acrylic resin, polyurethane resin, cellulose resin, butyral resin, polyamide resin, polyimide resin, polystyrene resin, polyether resin, gelatin, casein, starch, arabic rubber, poly (vinyl alcohol), poly (vinylpyrrolidone). , Cellulose, polyalkylene glycol and the like.
If there is concern about corrosion of the coating machine, etc., or adverse effects on the base material, ammonia, amine, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate may be added to the conductive polymer aqueous dispersion produced above. , A pH adjuster such as lithium hydroxide, sodium phosphate, calcium oxide, calcium hydroxide, magnesium oxide, magnesium hydroxide and the like may be added. However, since the addition of alkali causes dedoping of a doping agent such as PVA-PSS, the conductivity of the conductive polymer coating film generally decreases.

Next, a conductive polymer coating film using the above-mentioned conductive polymer aqueous dispersion and a method for producing the same will be described.
The conductive polymer coating film of the present invention is obtained by applying the above-mentioned conductive polymer aqueous dispersion or a composition of a conductive polymer aqueous dispersion and an additive on a substrate and drying the conductive polymer. It is a coating film. Further, in the method for producing a conductive polymer coating film of the present invention, the above-mentioned conductive polymer aqueous dispersion or a composition of a conductive polymer aqueous dispersion and an additive is applied onto a substrate and dried, which is conductive. This is a method for producing a sex polymer coating.

The method of applying the conductive polymer aqueous dispersion to various substrates is not particularly limited, such as spin coating, roll coating, spray coating, bar coating, screen printing, gravure printing, and inkjet printing. Then, the solvent may be removed by drying at 20 ° C. to 200 ° C. for 3 seconds to 1 week under normal pressure or reduced pressure.

The conductive polymer aqueous dispersion used in the production of the conductive polymer coating film of the present invention is applied alone or as a composition to which various additives are added on various substrates, and the applied material is dried. You can get it.
As the additive to be added, it can be used as a composition to which additives suitable for various uses such as a stabilizer for stabilizing the properties of the dispersion liquid, an antioxidant, and a preservative are added.

The conductive polymer coating film of the present invention has a reduced excess sulfonic acid that adversely affects moisture resistance and corrosion resistance, and has an antistatic coating, a solid electrolytic capacitor electrode, an electromagnetic wave shielding material, an actuator, and energy harvesting (power generation). ) In addition to materials, it is expected to be a substitute for lithium secondary batteries, sodium secondary batteries, organic thin-film solar cells, dye-sensitized solar cells, organic EL displays, electronic paper, touch panels, and other components, and ITO (indium tin oxide) transparent electrodes. it can.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited by these examples.

The analysis was performed as follows.
(1) Proton nuclear magnetic resonance spectrum measurement The spectrum was measured using DRX-500 manufactured by Bruker Biospin Co., Ltd., and the copolymer composition was calculated and the RAFT agent was identified. The composition ratio of the PVA-PSS block copolymer is the integral value (a) of 7.43 ppm and 6.52 ppm corresponding to the aromatic ring (4 protons) of the PSS segment and 3.91 corresponding to the methine proton (1 proton) of the PVA segment. It was calculated from the following equation from the integrated value of ppm (b).
PSS content (mol%) = 100 x (a / 4) / (a / 4 + b)
PVA content (mol%) = 100 x b / (a / 4 + b)

(2) Gel permeation chromatography (GPC) measurement (DMF system)
The molecular weights of thioester-terminated PVAc and RAFT-terminated PVAc were measured using HLC-8320 manufactured by Tosoh Corporation under the following conditions.
Column: TSK Guard Column Super AW-H / TSK Super AW-5000 / TSK Super AW-3000
Eluent: N, N'-dimethylformamide (containing 10 mM lithium bromide)
Sample concentration: Prepared to 0.05-0.1 wt% by dissolving in the above eluent Flow rate / injection amount / column temperature: 0.5 ml / min, injection amount 10 μl, column temperature 40 ° C
Detector: Differential Refractometer (RI)
Calibration curve: Prepared from peak top molecular weight and elution time using standard polyethylene oxide (manufactured by Tosoh Corporation).

(3) Gel permeation chromatography (GPC) measurement (HEIP system)
The molecular weight of PVA-SH was measured using HLC-8320 manufactured by Tosoh Corporation under the following conditions.
Column: TSK guard column HHR-H (S) / TSK gel HHR-H (S) / TSK gel HHR-M
Eluent: Hexafluoroisopropanol (containing 20 mM trifluoroacetic acid)
Sample concentration: 0.1wt%
Flow velocity / injection volume / column temperature: 0.2 ml / min, injection volume 10 μl, column temperature 40 ° C
Detector: RI detector Calibration curve: Prepared from peak top molecular weight and elution time using standard polymethylmethacrylate (manufactured by Sigma-Aldrich).

(4) Gel permeation chromatography (GPC) measurement (water-based)
The molecular weight of the PVA-PSS block copolymer was measured using HLC-8320 manufactured by Tosoh Corporation under the following conditions.
Column: TSK Guard Column Super AW-H / TSK Super AW-6000 / TSK Super AW-3000 / TSK Super AW-2500
Eluent: Sodium sulfate aqueous solution (0.05 mol / L) / acetonitrile = 65/35 volume ratio Sample concentration: Prepared to 0.05 to 0.1 wt% by dissolving in the above eluent Flow rate / injection amount / column temperature: 0.6 ml / min, Injection volume 10 μl, column temperature 40 ° C
Detector: UV detector (wavelength 230 nm) and RI detector Calibration curve: Standard sodium polystyrene sulfonate (manufactured by Sowa Kagaku) was used to prepare from peak top molecular weight and elution time.

(5) Measurement of degree of saponification Measurement was performed in accordance with JIS K6726-1994.
(6) Purification of Polymer by Dialysis Using a dialysis tube (Spectra / Por6, molecular weight cut-off 1000) manufactured by Spectrum Laboratories, dialysis was performed by stirring overnight in pure water.
(7) Purification of Conductive Polymer Aqueous Dispersion Solution by Ultrafiltration An Ultrafilter Q0100 (molecular weight cut off 10,000) manufactured by Advantech Co., Ltd. was used.
(8) Sonication of Conductive Polymer Aqueous Dispersion Solution An ultrasonic homogenizer UH-150 manufactured by SNT Co. Ltd. was used.
(9) Measurement of Particle Size of Conductive Polymer Aqueous Dispersion Nanotrack UPA-UT151 manufactured by Nikkiso Co., Ltd. was used.
(10) Preparation of Conductive Polymer Film (Freestanding Film) A conductive polymer aqueous dispersion was developed on a Teflon (registered trademark) petri dish with a radius of 2.5 cm, heated at 60 ° C for 6 hours and at 150 ° C for 1 hour, and then 150. A free-standing film was obtained by vacuum drying at ° C. for 1 hour.
(11) Film thickness measurement of conductive polymer film (self-supporting film) A digital micrometer MDC-25PJ manufactured by Mitutoyo Co., Ltd. was used.
(12) Measurement of Conductivity of Conductive Polymer Film (Self-supporting Film) The conductivity was measured by the four-probe method using a low resistivity meter Loresta GX manufactured by Mitsubishi Chemical Corporation.
(13) Hygroscopicity measurement of conductive polymer film (self-supporting film) Film after holding the vacuum-dried film in the environmental tester SH-241 manufactured by Espec Co., Ltd. (temperature 40 ° C, relative humidity 80%) for 6 hours. Hygroscopicity was evaluated from the weight increase rate of.

(14) Grid test of conductive polymer coating film The conductive polymer aqueous dispersion was spin-coated into a glass plate, heated at 60 ° C. for 6 hours, heated at 150 ° C. for 1 hour, and then vacuum dried at 150 ° C. for 1 hour. .. After preparing a grid pattern (25 squares) using a cross-cut guide, cellophane tape was applied and the cells were sufficiently crimped with fingers. The tape was peeled off within 5 minutes, and the adhesion before immersion in water was evaluated by observing the state of the coating film.
Further, the test piece having the above-mentioned lattice pattern formed is immersed in tap water at 40 ° C. for 6 hours, air-dried overnight at room temperature, and the peeled state with cellophane tape is observed in the same manner as described above. Was evaluated.

<Reagents used, etc.>
The compounds described in the examples used the following, but the present invention is not limited by these examples.
NaSS (sodium parastyrene sulfonate): Purity 88.9%, manufactured by Tosoh Finechem Co., Ltd.
VAc (vinyl acetate): purity 98%, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.
EDOT (3,4-ethylenedioxythiophene): purity 97%, thioacetic acid manufactured by Fujifilm Wako Pure Chemical Industries, Ltd .: purity 97%, cyanomethyl N-methyl-N-phenyldithiocarbamate manufactured by Fujifilm Wako Pure Chemical Industries, Ltd .: Made by Fujifilm Wako Pure Chemical Industries, Ltd.
AIBN [2,2'-azobis (isobutyronitrile)]: manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.
VA-086 [2,2'-azobis (2-methyl-N- (2-hydroxyethyl) propionamide]: manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. Potassium bromide: purity 99%, Fujifilm Wako Pure Chemical Industries, Ltd. Sodium persulfate: purity 97%, iron sulfate (III) n hydrate manufactured by Fujifilm Wako Pure Chemical Industries, Ltd .: pure content 60%, cation exchange resin manufactured by Fujifilm Wako Pure Chemical Industries, Ltd .: Lewatite MonoPlus100 sodium (Aldrich) Manufactured by, registered trademark) regenerated with 1N hydrochloric acid and washed with water Anion exchange resin: Lewatite MP-62 free base (manufactured by Aldrich, registered trademark)
PS-5 (sodium polystyrene sulfonate): molecular weight 85,000, manufactured by Tosoh Finechem Co., Ltd.

Synthesis Example 1: Synthesis of PVA-PSS (1) <Synthesis of PVA-SH (1)>
4 mL of methanol containing 24.6 g (280 mmol) of vinyl acetate and 8.0 mg (0.10 mmol) of thioacetic acid was collected in a glass reactor and degassed by bubbling with argon. The temperature of this solution is raised to 65 ° C. under an argon atmosphere, 44.0 mg (0.268 mmol) of 2,2'-azobis (isobutyronitrile) in methanol (4 mL) is added, and then 94.0 mg of thioacetic acid is added. A solution of (1.16 mmol) in methanol (2 mL) was added dropwise over 4 hours, and the mixture was heated and stirred at 65 ° C. for 3 hours. The monomer conversion rate calculated from the ¹ H-NMR spectrum of the reaction solution was 40.8%. The unreacted monomer was distilled off together with methanol under reduced pressure, and the operation of adding methanol again and distilling off was repeated, and then the mixture was dried to obtain a viscous solid. The number average molecular weight (hereinafter abbreviated as Mn) was 22,700, and the weight average molecular weight (hereinafter abbreviated as Mw) was 52,600.
A solution of 8.83 g of the above viscous solid, 12 mL of methanol, and 327.0 mg (7.93 mmol) of sodium hydroxide in methanol (5 mL) was collected in a glass reactor, and heated and stirred at 40 ° C. for 20 hours under an argon atmosphere. After the reaction, the produced precipitate was filtered and washed with methanol to obtain 4.42 g (yield: 87.3%) of PVA-SH (1) as a colorless solid. The degree of saponification was 98.1 mol%, Mn was 11,600, and Mw was 26,900.

<Synthesis of PVA-PSS (1)>
2.34 g (10.09 mmol) of 4-styrene sulfonic acid, 2.00 g (45.4 mmol in terms of monomer unit) of PVA-SH (1) and 21 mL of water were collected in a glass reactor and heated at 90 ° C. It was dissolved and degassed by bubbling with argon. After substitution with argon, 1 ml of an aqueous solution of 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide] 35.0 mg (0.121 mmol) was added dropwise to this aqueous solution over 1 hour, and 90 as it was. The mixture was heated and stirred at ° C. for 14 hours. The monomer conversion rate calculated from the ¹ H-NMR spectrum of the reaction solution was 100% (no residual monomer was observed). The polymerization solution was returned to room temperature, 50 g of a cation exchange resin was added, the mixture was stirred for 6 hours, and the mixture was filtered off. 20 g of anion exchange resin was added to the filtrate, and the mixture was stirred for 2 hours. After the anion exchange resin was filtered off, the filtrate was concentrated to obtain 57.9 g of an aqueous solution (solid content: 6.23 wt%) of PVA-PSS (1). ^{1 From the} integrated value in the ¹ H-NMR spectrum, the molar ratio of styrene sulfonic acid unit / vinyl alcohol unit was 18/82 (51/49 in terms of weight). Mn was 31,100 and Mw was 77,500. From the difference in molecular weight from PVA-SH, the Mn of the PSS segment was estimated to be 19,500.

Synthesis Example 2: Synthesis of PVA-PSS (2) <Synthesis of PVA-SH (2)>
4 mL of methanol containing 24.6 g (280 mmol) of vinyl acetate and 5.00 mg (0.0624 mmol) of thioacetic acid was collected in a glass reactor and degassed by bubbling with argon. The temperature of this solution is raised to 65 ° C. under an argon atmosphere, 44.0 mg (0.268 mmol) of 2,2'-azobis (isobutyronitrile) in methanol (4 mL) is added, and then 47.0 mg of thioacetic acid is added. A solution of (0.587 mmol) in methanol (2 mL) was added dropwise over 4 hours, and the mixture was heated and stirred at 65 ° C. for 3 hours. The monomer conversion rate calculated from the ¹ H-NMR spectrum of the reaction solution was 63.9%. The unreacted monomer was distilled off together with methanol under reduced pressure, and the operation of adding methanol again and distilling off was repeated, and then the mixture was dried to obtain a viscous solid. Mn was 46,300 and Mw was 117,400.
A solution of 13.83 g of the above viscous solid, 35 mL of methanol, and 368 mg (8.93 mmol) of sodium hydroxide in methanol (5 mL) was added to a glass reactor, and the mixture was heated and stirred at 40 ° C. for 20 hours under an argon atmosphere. After the reaction, the produced precipitate was filtered and washed with methanol to obtain 6.52 g (yield: 82.8%) of polyvinyl alcohol as a colorless solid. The degree of saponification was 98.0 mol%, Mn was 23,700, and Mw was 60,000.

<Synthesis of PVA-PSS (2)>
2.34 g (10.09 mmol) of 4-styrene sulfonic acid, 2.01 g (45.6 mmol in terms of monomer unit) of PVA-SH (2) and 21 ml of water were collected in a glass reactor and heated at 90 ° C. It was dissolved and degassed by bubbling with argon. After substitution with argon, 1 ml of an aqueous solution of 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide] 33.0 mg (0.114 mmol) was added dropwise to this aqueous solution over 1 hour, and 90 as it was. The mixture was heated and stirred at ° C. for 15 hours. The monomer conversion rate calculated from the ¹ H-NMR spectrum of the reaction solution was 84.8%. The polymerization solution was returned to room temperature, 50 g of the cation exchange resin was added, and the mixture was stirred for 6 hours, and then the cation exchange resin was filtered off. After adding 20 g of the anion exchange resin to the filtrate and stirring for 2 hours, the anion exchange resin was filtered off. Residual monomers were removed by dialysis of the filtrate in water overnight. After dialysis, the mixture was concentrated to obtain 79.4 g of an aqueous solution of PVA-PSS (2) (solid content: 3.86 wt%). ^{1 From the} integrated value in the ¹ H-NMR spectrum, the molar ratio of styrene sulfonic acid unit / vinyl alcohol unit was 16/84 (47/54 in terms of weight). As a result of GPC measurement, Mn was 71,300 and Mw was 171,000. From the difference in molecular weight from PVA-SH, the Mn of the PSS segment was estimated to be 47,600.

Synthesis Example 3: Synthesis of O-ethyl-S-cyanomethylxanthate 2.70 ml (39.8 mmol) of bromoacetonitrile, 6.41 g (40.0 mmol) of potassium ethylxanthate, and 50 ml of ethanol in a glass reactor under an argon atmosphere. Was collected and reacted at room temperature with stirring for 15 hours. After the reaction, water was added and the desired product was extracted with diethyl ether. The ether layer was dehydrated with magnesium sulfate, concentrated, and then distilled under reduced pressure (120 ° C., 1 kPa) to obtain 4.15 g of O-ethyl-S-cyanomethylxanthate as a yellow liquid (yield 70.8). %).

Synthesis Example 4: Synthesis of PVA-PSS (3) <Synthesis of PVA-SH (3)>
8.75 g (99.6 mmol) of vinyl acetate, 17.2 mg (0.105 mmol) of 2,2'-azobis (isobutyronitrile) and O-ethyl-S-cyanomethyl obtained in Synthesis Example 3 in a glass reactor. 165.0 mg (0.993 mmol) of xantate was collected and degassed by bubbling with argon. The mixed solution was heated and stirred at 60 ° C. for 12 hours under an argon atmosphere. The polymerization solution was dissolved in 10 ml of chloroform, dropped into hexane, the precipitate was filtered off, and vacuum dried to obtain 5.73 g of a colorless solid polyvinyl acetate (yield 66.5%). Mn measured by GPC (DMF system) was 10,500, and Mw was 14,100.
5.06 g of the above polyvinyl acetate (58.7 mmol as a monomer unit), 20 mL of methanol, and 186 mg (4.50 mmol) of sodium hydroxide were collected in a glass reactor, and heated and stirred at 40 ° C. for 24 hours under an argon atmosphere. After the reaction, the produced precipitate was filtered and washed with methanol to obtain 2.51 g (yield: 98.1%) of PVA-SH as a colorless solid. The degree of saponification was 98.6 mol%, Mn was 5,400, and Mw was 7,200.

<Synthesis of PVA-PSS (3)>
8.25 g (35.57 mmol) of sodium 4-styrene sulfonate, 881 mg of the above PVA-SH (3) (20.0 mmol in terms of monomer unit), and 40 ml of water were collected in a glass reactor, dissolved, and then bubbling with argon. Degassed by doing. 1 ml of an aqueous solution of 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide] 35.0 mg (0.121 mmol) was added dropwise to this aqueous solution over 1 hour, and the temperature was 90 ° C. under an argon atmosphere. Was heated and stirred for 15 hours. The polymerization solution was returned to room temperature, 50 g of a cation exchange resin was added, the mixture was stirred for 6 hours, and then filtered off. After adding 20 g of the anion exchange resin to the filtrate and stirring for 2 hours, the anion exchange resin was filtered off, and the filtrate was dialyzed in water overnight to remove residual monomers. By concentrating the filtrate, 173 g of an aqueous solution of PVA-PSS (3) (solid content 3.65 wt%) was obtained. ^{1 From the} integrated value in the ¹ H-NMR spectrum, the molar ratio of styrene sulfonic acid unit / vinyl alcohol unit was 64/36 (89/11 in terms of weight). Mn was 85,300 and Mw was 271,300, and Mn of the PSS segment was estimated to be 79,900 from the difference in molecular weight from PVA-SH.

Synthesis Example 5: Synthesis of PVA-PSS (4) <Synthesis of PVA-SH (4)>
8.75 g (99.6 mmol) of vinyl acetate, 5 ml of methanol, 17.2 mg (0.105 mmol) of 2,2'-azobis (isobutyronitrile) and cyanomethyl N-methyl-N-phenyldithiocarbamate 40 in a glass reactor. 0.0 mg (0.175 mmol) was collected and degassed by bubbling with argon. The mixed solution was heated and stirred at 60 ° C. for 12 hours under an argon atmosphere. The polymerization solution was dissolved in 10 ml of chloroform, dropped into hexane, the precipitate was filtered off, and vacuum dried to obtain 6.14 g of a colorless solid polyvinyl acetate (yield 70.2%). Mn measured by GPC (DMF system) was 52,000, and Mw was 62,400.
5.22 g of the above polyvinyl acetate (60.6 mmol as a monomer unit), 20 mL of methanol, and 186 mg (4.50 mmol) of sodium hydroxide were collected in a glass reactor, and heated and stirred at 40 ° C. for 24 hours under an argon atmosphere. After the reaction, the produced precipitate was filtered and washed with methanol to obtain 2.63 g (yield: 98.4%) of PVA-SH as a colorless solid. The degree of saponification was 98.6 mol%, Mn was 26,600, and Mw was 31,900.

<Synthesis of PVA-PSS (4)>
In a glass reactor, 4.00 g (17.25 mmol) of sodium 4-styrene sulfonate, 2.00 g of the above PVA-SH (4) (45.4 mmol in terms of monomer unit), and 21 ml of water were collected and dissolved, and then argon was used. Degassed by bubbling with. 1 ml of an aqueous solution of 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide] 35.0 mg (0.121 mmol) was added dropwise to this aqueous solution over 1 hour, and the temperature was 90 ° C. under an argon atmosphere. Was heated and stirred for 15 hours. The polymerization solution was returned to room temperature, 50 g of a cation exchange resin was added, the mixture was stirred for 6 hours, and then filtered off. After adding 20 g of the anion exchange resin to the filtrate and stirring for 2 hours, the anion exchange resin was filtered off, and the filtrate was dialyzed in water overnight to remove residual monomers. By concentrating the filtrate, 110 g of an aqueous solution (solid content 3.78 wt%) of PVA-PSS (4) was obtained. ^{1 From the} integrated value in the ¹ H-NMR spectrum, the molar ratio of styrene sulfonic acid unit / vinyl alcohol unit was 27/73 (64/36 in terms of weight). As a result of GPC measurement, Mn was 81,100 and Mw was 251,000. From the difference in molecular weight from PVA-SH, the Mn of the PSS segment was estimated to be 54,400.

Synthesis Example 6: Synthesis of PVA-PSS (5) <Synthesis of PVA-SH (5)>
8.75 g (99.6 mmol) of vinyl acetate, 5 ml of methanol, 17.2 mg (0.105 mmol) of 2,2'-azobis (isobutyronitrile) and cyanomethyl N-methyl-N-phenyldithiocarbamate 60 in a glass reactor. 0.0 mg (0.0.262 mmol) was collected and degassed by bubbling with argon. The mixed solution was heated and stirred at 60 ° C. for 12 hours under an argon atmosphere. The polymerization solution was dissolved in 10 ml of chloroform, dropped into hexane, the precipitate was filtered off, and vacuum dried to obtain 6.05 g of a colorless solid polyvinyl acetate (yield 69.1%). Mn measured by GPC (DMF system) was 36,000, and Mw was 43,200.
5.14 g (59.7 mmol as a monomer unit) of the above polyvinyl acetate, 20 mL of methanol, and 186 mg (4.50 mmol) of sodium hydroxide were collected in a glass reactor, and heated and stirred at 40 ° C. for 24 hours under an argon atmosphere. After the reaction, the produced precipitate was filtered and washed with methanol to obtain 2.55 g (yield: 97.0%) of PVA-SH as a colorless solid. The degree of saponification was 98.4 mol%, Mn was 18,400, and Mw was 22,100.

<Synthesis of PVA-PSS (5)>
2.00 g of the above PVA-SH (5) (45.4 mmol in terms of monomer unit) and 23 ml of water were collected in a glass reactor and dissolved, and then dilute sulfuric acid was added to adjust the pH to 2.70. To this, 6.00 g (25.87 mmol) of sodium 4-styrene sulfonate was added to dissolve the mixture, and the mixture was degassed by bubbling with argon. 2 ml of an aqueous solution containing 25 mg (0.150 mmol) of potassium bromate was added to this aqueous solution, and the mixture was heated and stirred at 65 ° C. for 20 hours under an argon atmosphere. The polymerization solution was returned to room temperature, 50 g of a cation exchange resin was added, the mixture was stirred for 6 hours, and then filtered off. After adding 20 g of the anion exchange resin to the filtrate and stirring for 2 hours, the anion exchange resin was filtered off, and the filtrate was dialyzed in water overnight to remove residual monomers. By concentrating the filtrate, 136 g of an aqueous solution (solid content 4.10 wt%) of PVA-PSS (5) was obtained. ^{1 From the} integrated value in the ¹ H-NMR spectrum, the molar ratio of styrene sulfonic acid unit / vinyl alcohol unit was 36/64 (72/28 in terms of weight). Mn was 74,000 and Mw was 229,400. From the difference in molecular weight from PVA-SH, the Mn of the PSS segment was estimated to be 55,600.

Example 1: Synthesis and evaluation of conductive polymer aqueous dispersion (1) 18.7 g (styrene sulfonic acid unit equivalent) of 6.23 wt% aqueous solution of PVA-PSS (1) obtained in Synthesis Example (1) in a glass reactor 3.05 mmol, 1.16 g by weight of copolymer), 310 μL (2.90 mmol) of 3,4-ethylenedioxythiophene and 40 ml of water were collected and sonicated for 10 minutes using an ultrasonic cleaner. It was. To this, 10 ml of an aqueous solution containing 39.0 mg (58.5 μmol) of iron (III) sulfate n hydrate, 760 mg (3.10 mmol) of sodium persulfate and 180 μl of concentrated sulfuric acid was added, and polymerization was started at 0 ° C. under an argon atmosphere. Then, the mixture was stirred at room temperature for 19 hours and then at 60 ° C. for 1 hour. After completion of the reaction, after ultrasonic treatment using an ultrasonic homogenizer for 10 minutes, about 10 g each of a cation exchange resin and an anion exchange resin was added, and the mixture was stirred for 6 hours. After the ion exchange resin is filtered off, the filtrate is concentrated by ultrafiltration to obtain 83.9 g of a poly (3,4-ethylenedioxythiophene) (hereinafter referred to as PEDOT) aqueous dispersion (1) ( A solid content of 1.72 wt% and a pH of 2.33) were obtained.

Table 1 shows the results of preparing an independent film and a glass coating film using the above PEDOT aqueous dispersion and evaluating their physical properties. As shown in Table 1, in the dispersion liquid of Comparative Example, a large shrinkage was observed at the time of preparing the free-standing film, whereas in the dispersion liquid of this example, no shrinkage was observed. Moreover, the gloss of the free-standing film of this example was clearly stronger than that of the comparative example. From the above, it is clear that the film-forming property of the examples is superior to that of the comparative example. Further, the hygroscopicity of the coating film obtained in this example is clearly lower than that of the comparative example, and it is clear that the hygroscopicity is excellent.
Further, in the grid test, the number of peeled coating films obtained in this example is clearly smaller than that in the comparative example, and it is clear that the adhesion of the coating film in this example is superior to that in the comparative example.

Example 2: Synthesis and evaluation of conductive polymer aqueous dispersion (2) 30.0 g (styrene sulfonic acid unit equivalent) of 3.86 wt% aqueous solution of PVA-PSS (2) obtained in Synthesis Example (2) in a glass reactor. 2.77 mmol, 1.16 g by weight of copolymer), 310 μL (2.90 mmol) of 3,4-ethylenedioxythiophene and 30 ml of water were collected and sonicated for 10 minutes using an ultrasonic cleaner. It was. To this, 10 ml of an aqueous solution containing 39.0 mg (58.5 μmol) of iron (III) sulfate n hydrate, 760 mg (3.10 mmol) of sodium persulfate and 180 μl of concentrated sulfuric acid was added, and polymerization was started at 0 ° C. under an argon atmosphere. Then, the mixture was stirred at room temperature for 19 hours and then at 60 ° C. for 1 hour. After completion of the reaction, after ultrasonic treatment with an ultrasonic homogenizer for 10 minutes, 10 g of each of a cation exchange resin and an anion exchange resin was added, and the mixture was stirred for 6 hours. After the ion exchange resin is filtered off, the filtrate is concentrated by ultrafiltration to obtain 86.7 g of an aqueous dispersion of poly (3,4-ethylenedioxythiophene) (solid content 1.46 wt%, pH 2.45). ) Was obtained.

Table 1 shows the results of preparing an independent film and a glass coating film using the above PEDOT aqueous dispersion and evaluating their physical properties. As shown in Table 1, in the dispersion liquid of Comparative Example, a large shrinkage was observed at the time of preparing the free-standing film, whereas in the dispersion liquid of this example, no shrinkage was observed. Moreover, the gloss of the self-supporting film prepared from the dispersion liquid of this example was clearly stronger than that of the comparative example. From the above, it is clear that the film-forming property of the examples is superior to that of the comparative example. Further, the hygroscopicity of the coating film obtained in this example is clearly lower than that of the comparative example, and it is clear that the hygroscopicity is excellent.
Further, in the grid test, the number of peeled coating films obtained in this example is clearly smaller than that in the comparative example, and it is clear that the adhesion of the coating film in this example is superior to that in the comparative example.

Example 3: Synthesis and evaluation of conductive polymer aqueous dispersion (3) 23.5 g (styrene sulfonic acid unit equivalent) of 4.87 wt% aqueous solution of PVA-PSS (3) obtained in Synthesis Example (3) in a glass reactor 5.49 mmol, copolymer weight 1.14 g), 310 μl (2.89 mmol) of 3,4-ethylenedioxythiophene and 45 ml of water were collected and subjected to ultrasonic treatment for 10 minutes using an ultrasonic washer. It was. To this, 10 ml of an aqueous solution containing 39.0 mg (58.5 μmol) of iron (III) sulfate n hydrate, 759 mg (3.09 mmol) of sodium persulfate and 180 μl of concentrated sulfuric acid was added, and polymerization was started at 0 ° C. under an argon atmosphere. Then, the mixture was stirred at room temperature for 19 hours and then at 60 ° C. for 1 hour. After completion of the reaction, after ultrasonic treatment with an ultrasonic homogenizer for 10 minutes, 10 g of each of a cation exchange resin and an anion exchange resin was added, and the mixture was stirred for 6 hours. After the ion exchange resin is filtered off, the filtrate is concentrated by ultrafiltration to obtain 144.0 g of an aqueous dispersion of poly (3,4-ethylenedioxythiophene) (solid content 1.55 wt%, pH 2.28). ) Was obtained.

Table 1 shows the results of preparing an independent film and a glass coating film using the above PEDOT aqueous dispersion and evaluating their physical properties. As shown in Table 1, in the dispersion liquid of Comparative Example, a large shrinkage was observed at the time of preparing the free-standing film, whereas in the dispersion liquid of this example, no shrinkage was observed. Moreover, the gloss of the self-supporting film prepared from the dispersion liquid of this example was clearly stronger than that of the comparative example. From the above, it is clear that the film-forming property of the examples is superior to that of the comparative example. Further, the hygroscopicity of the coating film obtained in this example is clearly lower than that of the comparative example, and it is clear that the hygroscopicity is excellent.
Further, in the grid test, the number of peeled coating films obtained in this example is clearly smaller than that in the comparative example, and it is clear that the adhesion of the coating film in this example is superior to that in the comparative example.

Example 4: Synthesis and evaluation of conductive polymer aqueous dispersion (4) 30.2 g (styrene sulfonic acid unit equivalent) of 3.78 wt% aqueous solution of PVA-PSS (4) obtained in Synthesis Example (5) in a glass reactor. 3.79 mmol, copolymer weight 1.14 g), 310 μl (2.89 mmol) of 3,4-ethylenedioxythiophene and 45 ml of water were collected and sonicated for 10 minutes using an ultrasonic cleaner. It was. To this, 10 ml of an aqueous solution containing 39.0 mg (58.5 μmol) of iron (III) sulfate n hydrate, 759 mg (3.09 mmol) of sodium persulfate and 180 μl of concentrated sulfuric acid was added, and polymerization was started at 0 ° C. under an argon atmosphere. Then, the mixture was stirred at room temperature for 19 hours and then at 60 ° C. for 1 hour. After completion of the reaction, after ultrasonic treatment with an ultrasonic homogenizer for 10 minutes, 10 g of each of a cation exchange resin and an anion exchange resin was added, and the mixture was stirred for 6 hours. After the ion exchange resin is filtered off, the filtrate is concentrated by ultrafiltration to obtain 87.30 g of an aqueous dispersion of poly (3,4-ethylenedioxythiophene) (solid content 1.55 wt%, pH 2.85). Got

Table 1 shows the results of preparing an independent film and a glass coating film using the above PEDOT aqueous dispersion and evaluating their physical properties. As shown in Table 1, in the dispersion liquid of Comparative Example, a large shrinkage was observed at the time of preparing the free-standing film, whereas in the dispersion liquid of this example, no shrinkage was observed. Moreover, the gloss of the self-supporting film prepared from the dispersion liquid of this example was clearly stronger than that of the comparative example. From the above, it is clear that the film-forming property of the examples is superior to that of the comparative example. Further, the hygroscopicity of the coating film obtained in this example is clearly lower than that of the comparative example, and it is clear that the hygroscopicity is excellent.
Further, in the grid test, the number of peeled coating films obtained in this example is clearly smaller than that in the comparative example, and it is clear that the adhesion of the coating film in this example is superior to that in the comparative example.

Example 5: Synthesis and evaluation of conductive polymer aqueous dispersion (5) 28.4 g (styrene sulfonic acid unit equivalent) of 4.10 wt% aqueous solution of PVA-PSS (5) obtained in Synthesis Example (6) in a glass reactor. 4.44 mmol, copolymer weight 1.16 g), 310 μl (2.89 mmol) of 3,4-ethylenedioxythiophene and 45 ml of water were collected and sonicated for 10 minutes using an ultrasonic cleaner. It was. To this, 10 ml of an aqueous solution containing 39.0 mg (58.5 μmol) of iron (III) sulfate n hydrate, 759 mg (3.09 mmol) of sodium persulfate and 180 μl of concentrated sulfuric acid was added, and polymerization was started at 0 ° C. under an argon atmosphere. Then, the mixture was stirred at room temperature for 19 hours and then at 60 ° C. for 1 hour. After completion of the reaction, after ultrasonic treatment with an ultrasonic homogenizer for 10 minutes, 10 g of each of a cation exchange resin and an anion exchange resin was added, and the mixture was stirred for 6 hours. After the ion exchange resin is filtered off, the filtrate is concentrated by ultrafiltration to obtain 94.30 g of an aqueous dispersion of poly (3,4-ethylenedioxythiophene) (solid content 1.51 wt%, pH 2.80). ) Was obtained.

Table 1 shows the results of preparing an independent film and a glass coating film using the above PEDOT aqueous dispersion and evaluating their physical properties. As shown in Table 1, in the dispersion liquid of Comparative Example, a large shrinkage was observed at the time of preparing the free-standing film, whereas in the dispersion liquid of this example, no shrinkage was observed. Moreover, the gloss of the self-supporting film prepared from the dispersion liquid of this example was clearly stronger than that of the comparative example. From the above, it is clear that the film-forming property of the examples is superior to that of the comparative example. Further, the hygroscopicity of the coating film obtained in this example is clearly lower than that of the comparative example, and it is clear that the hygroscopicity is excellent.
Further, in the grid test, the number of peeled coating films obtained in this example is clearly smaller than that in the comparative example, and it is clear that the adhesion of the coating film in this example is superior to that in the comparative example.

Comparative Example (1): Synthesis and Evaluation of Conductive Polymer Aqueous Dispersion Solution (6) 15.1 wt% Poly by cation exchange treatment of sodium polystyrene sulfonate (product name PS-5) manufactured by Toso Finechem Co., Ltd. An aqueous solution of (4-styrene sulfonic acid) (PS-5H) was obtained.
In a glass reactor, 7.34 g of PS-5H (6.05 mmol in terms of styrene sulfonic acid unit, 1.11 g in polymer weight), 310 μL of 3,4-ethylenedioxythiophene (2.92 mmol) and 30 ml of water were collected. , The ultrasonic treatment was performed for 10 minutes using an ultrasonic cleaner. To this, add 39.0 mg (58.5 μmol) of iron (III) sulfate n hydrate, 760 mg (3.19 mmol) of sodium persulfate, and 10 mL of an aqueous solution of 180 μL (3.19 mmol) of concentrated sulfuric acid, and add 0 under an argon atmosphere. The polymerization was started at ° C., and the mixture was stirred at room temperature for 19 hours and then at 60 ° C. for 1 hour. After the reaction, after ultrasonic treatment with an ultrasonic homogenizer for 10 minutes, 10 g of each of a cation exchange resin and an anion exchange resin was added, and the mixture was stirred for 6 hours. After the ion exchange resin is filtered off, the filtrate is concentrated by ultrafiltration to obtain 80.3 g of an aqueous dispersion of poly (3,4-ethylenedioxythiophene) (solid content 1.58 wt%, pH 2.12). ) Was obtained.

Table 1 shows the results of preparing an independent film and a glass coating film using the above PEDOT aqueous dispersion and evaluating their physical properties. As shown in Table 1, the dispersion liquid of the above-mentioned example did not show shrinkage during the preparation of the self-supporting film, whereas the dispersion liquid of this comparative example showed a large shrinkage. Moreover, the gloss of the self-supporting film prepared from the dispersion liquid of this comparative example was clearly inferior to that of the example. From the above, it is clear that the film-forming property of the comparative example is inferior to that of the example. Further, the hygroscopicity of the coating film obtained in this comparative example is clearly higher than that of the examples, and it is clear that the hygroscopicity is inferior.
Further, in the grid test, the number of peels of the coating film obtained in this comparative example is clearly larger than that in the example, and it is clear that the adhesion of the coating film in this comparative example is superior to that in the example.

Since the conductive polymer coating film obtained from the conductive polymer aqueous dispersion of the present invention has excellent moisture resistance and adhesion, it is used as an antistatic coating, a solid electrolytic capacitor electrode, an electromagnetic wave shielding material, an actuator, and an energy harvesting (power generation) material. In addition, it can be expected as a substitute for lithium secondary batteries, sodium secondary batteries, organic thin-film solar cells, dye-sensitized solar cells, organic EL displays, electronic paper, touch panels and other members, and ITO (indium tin oxide) transparent electrodes.

Claims (6)

A block copolymer composed of a vinyl alcohol-based polymer segment (A) and a styrene-sulfonic acid-based polymer segment (B) as a dispersant and dopant, and
With conductive polymer
Only including,
The weight ratio (A) / (B) of the vinyl alcohol-based polymer segment (A) to the styrene sulfonic acid-based polymer segment (B) is 10/90 to 90/10.
An aqueous dispersion of a conductive polymer having a weight ratio of the block copolymer to the conductive polymer of 100/100 to 500/100 . The degree of saponification of the vinyl alcohol-based polymer segment (A) is 70% or more, and the number average molecular weight determined by gel permeation chromatography is 5,000 to 100,000.
The number average molecular weight determined by gel permeation chromatography of the styrene sulfonic acid polymer segment (B) is 5,000 to 100,000.
The weight ratio of vinyl alcohol polymer segment (A) and styrene sulfonic acid polymer segment (B) is (A) / (B), 10/90 to 90 is / 10, the conductive polymer aqueous claim 1 Dispersion solution. The aqueous dispersion of a conductive polymer according to claim 1 or 2, wherein the conductive polymer is poly (3,4-ethylenedioxythiophene) or a derivative thereof. The conductive polymer aqueous dispersion according to any one of claims 1 to 3 or the composition of the conductive polymer aqueous dispersion and the additive is applied onto the substrate and dried. Conductive polymer coating. A conductive polymer aqueous dispersion according to any one of claims 1 to 3 or a composition of the conductive polymer aqueous dispersion and an additive is applied onto a substrate and dried. A method for producing a polymer coating film. The method for producing an aqueous dispersion of a conductive polymer according to any one of claims 1 to 3 , wherein the monomer of the conductive polymer is oxidatively polymerized in an aqueous solvent containing a block copolymer.