Polythiophene / Polyanionic Composition

Abstract

A conductive polymer dispersion comprising polythiophene and a polyanion, wherein the polyanion is a homopolymer or copolymer of a monomer according to the following chemical formula I: In the above formula, Any of R1 to R5 is selected from the group consisting of hydrogen, halogens, ethers, and substituted or unsubstituted alkyl groups, provided that at least one of R1 to R5 is a substituent according to the following chemical formula II; In the above formula, L represents a divalent linker having fewer than 20 carbon atoms; n represents 0 or 1; R6 and R7 are independently selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, and a substituted or unsubstituted aryl or heteroaryl group; Any of L, R6, and R7 may represent atoms necessary to form a 5- to 8-membered ring; M represents a hydrogen or counterion to compensate for the negative charge of the sulfonate group; The dashed line indicates the covalent bond to the phenyl ring of chemical formula I.

Description

Technology Field

[0001] The present invention relates to a novel polythiophene / polyanion composition and its use in various applications, such as polymer capacitors. Background Technology

[0002] Environmental concerns regarding greenhouse gas emissions have stimulated demand for battery electric vehicles and (plug-in) hybrid electric vehicles as battery capacity increases. Control units in these automotive electronics include several so-called polymer capacitors.

[0003] Due to operation at higher voltages and higher converter frequencies, capacitors can be exposed to high temperatures. Therefore, the reliability of these capacitors at high temperatures is one of the critical characteristics of these devices in electric vehicles.

[0004] Polymer hybrid aluminum-electrolytic capacitors are frequently applied in this field. These capacitors consist of an etched aluminum / aluminum oxide (Al / Al2O3) foil acting as an electrode and a dielectric layer coated with a conductive polymer layer acting as a counter electrode. Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS), a conductive polymer composite coated onto an Al / Al2O3 substrate by dip coating from an aqueous dispersion, is commonly used. The temperature stability of the conductive polymer film directly affects the reliability of the capacitor at high temperatures. In the case of PEDOT:PSS, the polyanionic PSS is associated with decomposition at higher temperatures, thereby limiting the reliability of the conductive polymer layer.

[0005] The manufacture of these capacitors is carried out by dip-coating capacitor elements into an aqueous dispersion of PEDOT:PSS. These dispersions generally have a pH of 1.5 to 2 due to the acidity of the PSS polymer. However, the Al2O3 layer acting as the dielectric layer of the capacitor is stable in a pH range of 4 to 8.5. Therefore, the conductive polymer dispersion is typically neutralized using a base to a pH within this range. However, in the case of PEDOT:PSS dispersions, this results in an increase in the surface resistance of the resulting PEDOT:PSS layer. The higher surface resistance of the polymer layer is associated with an increase in the equivalent series resistance (ESR) of the capacitor.

[0006] An additional aspect of the fabrication of these capacitors is the infiltration of conductive polymer particles into the Al / Al2O3 foil. To increase the surface area, an etched foil of Al is used, which is then anodized to provide a thin layer of Al2O3. This process produces a porous Al / Al2O3 substrate dip-coated with an aqueous PEDOT:PSS dispersion. Thus, the particle size of the conductive polymer particles determines the polymer's ability to penetrate the pores of the Al / Al2O3 substrate. A lower median particle size of the conductive polymer dispersion typically produces a superior coating. Additionally, the particle size is preferably kept small within the stable pH range of the aforementioned aluminum oxide material.

[0007] PSS is commonly used as a dispersant for PEDOT in aqueous dispersions.

[0008] US2018 / 240564 (Shin Etsu Chemicals) describes so-called dopant polymers having a benzamide or acrylamide structure and a sulfonyl group as substitutes for PSS. These polymers, used alone or in combination with PSS, improve the filterability and coating properties of the resulting aqueous PEDOT dispersion.

[0009] KR102211924 (Yonsei University) discloses a copolymer of styrene sulfonic acid and styrene fluoride or acrylate monomers. The use of these improves the flexibility, solution stability, and coating properties of the resulting PEDOT dispersion.

[0010] JP6785390 (Sagami Central Chemical Research Center) discloses the use of styrene sulfonic acid and vinyl alcohol for preparing copolymer dispersants for PEDOT. These copolymers exhibit improved film formation and lower hygroscopicity compared to PSS. However, lower adhesion is observed.

[0011] In JP2020 / 183493 (Tosoh), a copolymer of an acrylsulfonate monomer and styrene sulfonic acid is described. With this copolymer, smaller PEDOT:polyanionic particles are obtained.

[0012] US2018 / 068801 (Panasonic) discloses so-called acrylic-type polymer dopants prepared from three different monomers each having a sulfonate group, a carboxyl group, and a hydroxyl group. These polymer dopants are used in PEDOT dispersions used in the manufacture of polymer capacitors.

[0013] In US2020 / 279692 (Panasonic), the heat resistance of a polymer capacitor is improved by forming different conductive layers on top of each other and applying a so-called treatment liquid between each conductive layer. The treatment liquid contains small molecule additives such as naphthalenesulfonic acid. In US2020 / 211785 (Panasonic), such treatment liquid contains an aromatic carboxylic acid.

[0014] US2015 / 0279503 (Heraeus Precious Metals) discloses a method for manufacturing a capacitor comprising a dispersion, a dispersant, and a complex of polythiophene and a polyanion, wherein the weight ratio of polythiophene to polyanion in the dispersion is greater than 0.5.

[0015] The conductive polymer dispersion, which improves the temperature stability of a conductive polymer layer formed using the conductive polymer dispersion, can improve the high-temperature reliability of a polymer capacitor. Additionally, when the dispersion is used in a pH range of 4 to 8.5 without increased particle size or increased surface resistance of the generated conductive polymer layer, the ESR of the polymer capacitor can also be improved. Finally, a dispersion having a lower median particle size will further improve the ESR of the generated capacitor due to improved penetration of the conductive polymer particles into the porous substrate.

[0016] Therefore, there is a need for a PSS substitute to prepare a stable aqueous PEDOT dispersion. It has been confirmed that using a PSS substitute having a linker between the styrene group and the sulfonic acid group improves the thermal stability of the conductive polymer layer without significantly affecting other properties of the conductive polymer layer, enables processing at higher pH levels, and reduces the particle size of the conductive polymer dispersion.

[0017] The object of the present invention is to provide a dispersion containing a conductive polymer that enables the realization of a polymer capacitor having improved high-temperature reliability and equivalent surface resistance (ESR).

[0018] The object of the present invention is realized by a dispersion as defined in claim 1 of the claims.

[0019] Further objects of the present invention will become apparent from the following description. Specific details for implementing the invention

[0020] definition

[0021] For example, in monofunctional polymerizable compounds, the term "monofunctional" means that the polymerizable compound contains one polymerizable group.

[0022] For example, in difunctional polymerizable compounds, the term "difunctional" means that the polymerizable compound contains two polymerizable groups.

[0023] For example, in polyfunctional polymerizable compounds, the term "polyfunctional" means that the polymerizable compound contains more than two polymerizable groups.

[0024] The term "alkyl" means all possible variants for each number of carbon atoms in the alkyl group, namely methyl; ethyl; for 3 carbon atoms, n-propyl and isopropyl; for 4 carbon atoms, n-butyl, isobutyl and tert-butyl; for 5 carbon atoms, n-pentyl, 1,1-dimethyl-propyl, 2,2-dimethylpropyl and 2-methyl-butyl, etc.

[0025] Unless otherwise specified, the substituted or unsubstituted alkyl group is preferably a C1 to C6-alkyl group.

[0026] Unless otherwise specified, the substituted or unsubstituted alkenyl group is preferably a C2 to C6-alkenyl group.

[0027] Unless otherwise specified, the substituted or unsubstituted alkynyl group is preferably a C2 to C6-alkynyl group.

[0028] Unless otherwise specified, the substituted or unsubstituted alkalil group is preferably a phenyl or naphthyl group comprising one, two, three or more C1 to C6-alkyl groups.

[0029] Unless otherwise specified, the substituted or unsubstituted aralkyl group is preferably a C7 to C group comprising a phenyl group or a naphthyl group. 20 - It is an alkyl group.

[0030] Unless otherwise specified, the substituted or unsubstituted aryl group is preferably a phenyl group or a naphthyl group.

[0031] Unless otherwise specified, the substituted or unsubstituted heteroaryl group is preferably a pentagonal or hexaagonal ring substituted by one, two, or three oxygen atoms, nitrogen atoms, sulfur atoms, selenium atoms, or a combination thereof.

[0032] Unless otherwise specified, the substituted or unsubstituted alkylene group is preferably a C1 to C6-alkylene group.

[0033] For example, in substituted alkyl groups, the term "substituted" means that the alkyl group can be substituted by atoms other than those usually present in such groups, namely carbon and hydrogen. For example, a substituted alkyl group may include a halogen atom or a thiol group. An unsubstituted alkyl group contains only carbon and hydrogen atoms.

[0034] Unless otherwise specified, the substituted alkyl group, substituted alkenyl group, substituted alkynyl group, substituted aralkyl group, substituted alkaryl group, substituted aryl and substituted heteroaryl group are preferably substituted by one or more components selected from the group consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and tert-butyl, esters, amides, amines, ethers, thioethers, ketones, aldehydes, sulfoxides, sulfones, sulfonate esters, sulfonamides, -Cl, -Br, -I, -OH, -SH, -CN and -NO2.

[0035] conductive polymer dispersion

[0036] A dispersion containing a conductive polymer is referred to herein as a conductive polymer dispersion.

[0037] The conductive polymer dispersion according to the present invention comprises a polyanion and a conductive polymer as described below.

[0038] As described below, polythiophene is preferably prepared in the presence of a polyanion. The polyanion can stabilize the polythiophene to form polythiophene / polyanion particles dispersed in a dispersion medium, preferably water.

[0039] The conductive polymer dispersion is preferably an aqueous dispersion.

[0040] The mass ratio of poly(thiophene) and polyanion is in the range of 1:10 to 10:1, more preferably 1:5 to 5:1, and most preferably 1:3 to 3:1.

[0041] The dispersion medium of the conductive polymer dispersion is water, a water-soluble organic solvent, or a mixture thereof. A preferred organic solvent is a protic organic solvent such as an alcohol or an acid. The dispersion medium is preferably water.

[0042] The conductive polymer dispersion may include other components, such as a dispersant, for example.

[0043] The conductive polymer dispersion is preferably prepared as described below.

[0044] polyanion

[0045] The conductive polymer dispersion comprises a polyanion that is a homopolymer or copolymer of a monomer according to the following chemical formula I:

[0046] <Chemical Formula I>

[0047]

[0048] In the above formula,

[0049] Any of R1 to R5 is selected from the group consisting of hydrogen, halogens, ethers, and substituted or unsubstituted alkyl groups, provided that at least one of R1 to R5 is a substituent according to the following chemical formula II;

[0050] <Chemical Formula II>

[0051]

[0052] In the above formula, L represents a divalent linker having fewer than 20 carbon atoms;

[0053] n represents 0 or 1;

[0054] R6 and R7 are independently selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, and a substituted or unsubstituted aryl or heteroaryl group;

[0055] Any of L, R6, and R7 may represent atoms necessary to form a 5- to 8-membered ring;

[0056] M represents a hydrogen or counterion to compensate for the negative charge of the sulfonate group;

[0057] The dashed line indicates the covalent bond to the phenyl ring of chemical formula I.

[0058] L is preferably selected from the group consisting of a substituted or unsubstituted alkylene group, a substituted or unsubstituted alkenylene group, and a substituted or unsubstituted alkynylene group, and a substituted or unsubstituted alkylene group is more preferred.

[0059] L is preferably a substituted or unsubstituted C1 to C 10 It is an alkylene group, more preferably a substituted or unsubstituted C1 to C5 alkylene group.

[0060] Preferably, n represents 0.

[0061] R6 and R7 are preferably independently selected from the group consisting of hydrogen and substituted or unsubstituted alkyl groups, with hydrogen being the most preferred.

[0062] In a preferred embodiment, only one of R1 to R5 is a substituent represented by Chemical Formula II.

[0063] In another preferred embodiment, one of R2, R3 and R4 is a substituent represented by Formula II.

[0064] In another preferred embodiment, all substituents not represented by Formula II are hydrogen.

[0065] In a particularly preferred embodiment, R3 is a substituent represented by Formula II, and R1, R2, R4, and R5 represent hydrogen.

[0066] M is preferably a quaternary ammonium group, H + or Na + It represents, and most preferably, M is H + It represents.

[0067] Typical monomers according to chemical formula I are disclosed in Table 1 below.

[0068]

[0069]

[0070]

[0071]

[0072] The polyanion may be a copolymer of a monomer according to chemical formula I and at least one other monomer.

[0073] In these copolymers, the amount of monomer according to formula I is preferably at least 25 mol%, more preferably at least 50 mol%, most preferably at least 75 mol%, and particularly preferably at least 90 mol% with respect to the total amount of monomer units of the copolymer.

[0074] A copolymer having styrene sulfonic acid is a particularly desirable copolymer.

[0075] However, a homopolymer of the monomer according to chemical formula I is most desirable.

[0076] The weight average molecular weight (Mw) of the polyanion is preferably 1,000 to 1,000,000 Da, more preferably 50,000 to 500,000 Da, and most preferably 100,000 to 300,000 Da.

[0077] Typical polyanions according to the present invention are shown in Table 2 below.

[0078] Table 2

[0079]

[0080] X + Y is 1, and X is preferably 0.25 to 1, more preferably 0.50 to 1, most preferably 0.75 to 1, and particularly preferably 0.9 to 1.

[0081] In addition to the polyanions described above, the conductive polymer dispersion may include one or more other polyanions. For example, the polyanions described above may be combined with PSS.

[0082] conductive polymer

[0083] A conductive polymer dispersion contains a conductive polymer.

[0084] The conductive polymer is preferably polythiophene.

[0085] These polythiophenes typically have a positive charge located on the main chain of the polymer. The positive charge is preferably compensated at least partially by anions.

[0086] When anions are covalently bonded to a polymer, the polymer is often referred to as a self-doped polymer or an intrinsically conductive polymer. Monomers containing anionic groups, which are used to manufacture such self-doped polymers, are also referred to as self-doped monomers.

[0087] When the anion is a separate compound, the polymer is typically referred to as a foreign-doped polymer or an extrinsically conductive polymer. The anion added as a separate compound is preferably a polyanion.

[0088] Non-intrinsic conductive polymer.

[0089] The conductive polymer dispersion includes a non-intrinsic conductive polymer.

[0090] Non-intrinsic conductive polymers as described herein have a positive charge located on the main chain, which is at least partially compensated by anions not covalently bonded to the polymer.

[0091] In the present invention, the cation charge of the non-intrinsic conductive polymer is at least partially compensated by the polyanion as described above.

[0092] The non-intrinsic conductive polymer is preferably polythiophene. The polythiophene may be a homopolymer or a copolymer.

[0093] A preferred exogenously doped polythiophene is disclosed in EP-A 440957, page 2, line 46 to page 3, line 14.

[0094] A preferred polythiophene is represented by the following chemical formula III:

[0095] Chemical Formula III

[0096]

[0097] In the above formula,

[0098] 2 < n ≤ 100 and,

[0099] R a and R b represents independently hydrogen, a substituted or unsubstituted C1-C4 alkyl group, or together with a substituted or unsubstituted C1-C04 alkylene group or a substituted or unsubstituted C3-C 10It forms a cycloalkylene group.

[0100] Preferably, n is an integer from 3 to 50, more preferably from 4 to 20.

[0101] Preferably, R a and R b is independently an unsubstituted ethylene group, an unsubstituted methylene group, optionally an alkyl-substituted methylene group, optionally C 1-12 It represents an alkyl- or phenyl-substituted ethylene group, an unsubstituted 1,3-propylene group, or an unsubstituted 1,2-cyclohexylene group.

[0102] The preferred polythiophene is a homopolymer or copolymer of 3,4-dialkoxythiophene selected from the group consisting of 3,4-methylenedioxythiophene, 3,4-ethylenedioxythiophene, 3,4-propylenedioxythiophene, 3,4-butylenedioxythiophene and derivatives thereof, which forms an oxy-alkylene-oxy bridge in which two of the alkoxy groups are selectively substituted.

[0103] These polymers are described in Handbook of Oligo- and Polythiophenes Edited by D. Fichou, Wiley-VCH, Weinheim (1999). [by L. Groenendaal et al. in Advanced Materials, volume 12, pages 481-494 (2000)]; [LJ Kloeppner et al. in Polymer Preprints, volume 40(2), page 792 (1999)]; [P. Schottland et al. in Synthetic Metals, volume 101, pages 7-8 (1999)]; and [DM Welsh et al. in Polymer Preprints, volume 38(2), page 320 (1997)].

[0104] A particularly desirable non-intrinsic conductive polymer is polyethylene-dioxythiophene (PEDOT), which is a homopolymer of 3,4-ethylene-dioxythiophene (EDOT).

[0105] intrinsic conductive polymer

[0106] In the method for manufacturing a polymer capacitor described below, an intrinsically conductive polymer may also be used in combination with the non-intrinsically conductive polymer described above.

[0107] Preferably, such intrinsic conductive polymers are used as a separate polymer conductive dispersion in addition to the polymer conductive dispersion containing the non-intrinsic conductive polymer and polyanion described above.

[0108] The intrinsically conductive polymer as described herein means that it has a positive charge located on the main chain, which is at least partially compensated by anions covalently bonded to the polymer.

[0109] Such intrinsically conductive polymers are disclosed, for example, in EP-A 1122274.

[0110] A preferred intrinsic conductive polymer is a thiophene homopolymer or copolymer of monomers according to the following chemical formula IV:

[0111] <Chemical Formula IV>

[0112]

[0113] In the above formula,

[0114] A represents a substituted or unsubstituted C1 to C5 alkylene crosslink further functionalized with at least one functional group selected from the group consisting of sulfonic acid or its salt, phosphonic acid or its salt, phosphate ester or its salt, sulfate ester or its salt, and carboxylic acid or its salt.

[0115] In chemical formula IV, A preferably represents a C2-alkylene crosslink.

[0116] A more desirable intrinsic conductive polymer is a thiophene (co)polymer of monomers according to the following chemical formula V:

[0117] Chemical Formula V

[0118]

[0119] In the above formula,

[0120] L1 represents a divalent linker containing 1 to 15 carbon atoms, and

[0121] C represents a functional group selected from the group consisting of sulfonic acid or its salt, phosphonic acid or its salt, phosphate ester or its salt, sulfate ester or its salt, and carboxylic acid or its salt.

[0122] C preferably represents sulfonic acid or a salt thereof.

[0123] A particularly desirable intrinsic conductive polymer is a thiophene homopolymer or copolymer comprising monomer units according to the following chemical formula VI:

[0124] Chemical Formula VI

[0125]

[0126] In the above formula,

[0127] L2 represents a divalent linker containing 10 or fewer carbon atoms, and

[0128] M represents hydrogen or a counterion to compensate for the negative charge of the sulfonate group.

[0129] Typical self-doped monomers according to Chemical Formula IV are shown in Table 3 below.

[0130] Table 3

[0131]

[0132]

[0133] Manufacturing of conductive polymers

[0134] Polythiophene polymers are preferably prepared by the oxidative polymerization of thiophene monomers in an aqueous medium.

[0135] In the case of foreign-doped polythiophene, oxidative polymerization is preferably carried out in the presence of a polyanion.

[0136] The concentration of thiophene monomer in the aqueous phase medium is preferably in the range of 0.1 to 25 weight% and preferably in the range of 0.5 to 10 weight% with respect to the total weight of the aqueous reaction medium.

[0137] Suitable oxidizing agents are iron(III) salts such as FeCl3, and iron(III) salts of aromatic and aliphatic sulfonic acids; H2O2; K2Cr2O7; alkali metal perborates; alkali metal or ammonium persulfates; and mixtures thereof.

[0138] Additional suitable oxidizing agents are described, for example, in the literature [Handbook of Conducting Polymers (Ed. Skotheim, TA), Marcel Dekker: New York, 1986, Vol. 1, pages 46-57].

[0139] Particularly desirable oxidizing agents are salts of peroxydisulfate, particularly K2S2O8, Na2S2O8; iron(III) salts, particularly iron(III) chloride; or combinations thereof.

[0140] A mixture of a salt of peroxydisulfate and at least one additional compound that catalyzes the cleavage of peroxydisulfate, such as a Fe(III)-salt, is particularly preferred.

[0141] According to a particularly preferred embodiment, the oxidizing agent is a mixture of Fe2(SO4)3 and Na2S2O8.

[0142] There are different ways to prepare an aqueous reaction medium. A thiophene monomer may be dissolved or dispersed in the aqueous reaction medium, and then an oxidizing agent(s) that may also be dissolved or dispersed in the aqueous phase may be added, or the oxidizing agent(s) may first be dissolved or dispersed in the aqueous reaction medium, and then a thiophene monomer that may also be dissolved or dispersed in the aqueous phase may be added.

[0143] When more than one oxidizing agent, for example, a mixture of Fe2(SO4)3 and Na2S2O8 is used, it is also possible to first mix one of these components, for example Fe2(SO4)3, with a thiophene monomer in an aqueous reaction medium, and then add a second oxidizing agent, for example Na2S2O8.

[0144] Oxidative polymerization is preferably carried out under an inert atmosphere as disclosed in EP-11453877 (Agfa Gevaert). When an oxidizing agent, for example, a salt of peroxydisulfate, is added to the reaction medium, the oxygen content of the reaction medium is preferably less than 3 mg per liter, more preferably less than 1.5 mg / liter, and most preferably less than 0.5 mg / liter.

[0145] The concentration of oxygen in the reaction medium can be controlled by any means, such as freeze-thaw technology, long-term bubbling of an inert gas such as argon, nitrogen, or helium through the reaction medium, or the consumption of oxygen in a sacrificial reaction under an inert gas blanket. The inert gas is preferably bubbled through the reaction medium until the polymerization is completed, thereby maintaining an oxygen concentration of less than 3 mg / l.

[0146] Oxidative polymerization is preferably carried out at a low pH as disclosed in EP-A 1384739 (Heraeus). The pH is preferably 1.5 or lower, more preferably 1.00 or lower.

[0147] To adjust the pH, the acid is preferably selected from the group of water-soluble inorganic acids and water-soluble organic acids. Examples of inorganic acids are hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid. Examples of organic acids include p-toluenesulfonic acid, benzenesulfonic acid, methanesulfonic acid, and trifluoromethanesulfonic acid.

[0148] The temperature of the reaction mixture is preferably 0 to 100°C, more preferably 0 to 50°C, and most preferably 5 to 30°C.

[0149] The amounts of thiophene monomer and polyanion in the reaction mixture are selected so as to obtain a stable polythiophene / polyanion dispersion having a solid content preferably 0.05 to 25 weight%, more preferably 0.1 to 10 weight%, and most preferably 0.8 to 2 weight%.

[0150] After the polymerization reaction is completed, the liquid composition may be further purified, for example, by filtration, particularly by ultrafiltration and / or by treatment with an ion exchanger, particularly by treatment with an anion exchanger and a cation exchanger.

[0151] After the purification step, the conductive polymer dispersion can be further optimized for the application in which it will be used. For example, when used in the manufacture of polymer capacitors, the polymer capacitor formulation described below can be prepared from the conductive polymer dispersion.

[0152] Various homogenization techniques can be used during the manufacture of conductive polymers. Homogenization techniques can be selected from the following:

[0153] - Ultrasonic homogenization technology;

[0154] - Pressure homogenization technology; and

[0155] - Mechanical homogenization technology.

[0156] Desirable mechanical homogenizers are rotor-stator homogenizers and blade-type homogenizers. Another mechanical homogenization technique may be the use of a spinning disk reactor.

[0157] For example, desirable high-pressure homogenizers, such as Gaulin homogenizers or Ariete homogenizers, force the dispersion through very narrow channels or orifices under pressure. Another desirable high-pressure homogenizer is a microfluidizer.

[0158] Two or more types of homogenizers can be combined and preferably used in a continuous manner.

[0159] Homogenization technology can be used before, during, and after the polymerization reaction. This homogenization technology can also be used during the preparation of the liquid formulations described below.

[0160] Liquid formulation

[0161] Depending on the application in which the conductive polymer dispersion is used, additional components may be added to the conductive polymer dispersion to form a liquid formulation optimized for that application.

[0162] For example, when used in the manufacture of polymer capacitors, this liquid formulation may be referred to as a polymer capacitor formulation.

[0163] All or part of the additional components described below may be added to the conductive polymer dispersion mentioned above.

[0164] In addition to the aforementioned conductive polymer and polyanion, the formulation may include additional additives such as a surface active material, an adhesion promoter, a crosslinking agent, a binder, a conductivity-increasing compound, a thermal and moisture stability-improving compound, an acidic compound, and an alkaline compound.

[0165] Surface-active compounds can be as follows:

[0166] - Anionic surfactants, e.g., alkylbenzenesulfonic acids and salts, paraffin sulfonates, alcohol sulfonates, ether sulfonates, sulfosuccinates, phosphate esters, alkyl ether carboxylic acids or carboxylates;

[0167] - Cationic surfactants, e.g., quaternary alkylammonium salts;

[0168] - Nonionic surfactants, e.g., linear alcohol ethoxylates, oxo alcohol ethoxylates, alkylphenol ethoxylates, or alkyl polyglucosides; and

[0169] - Zionic surfactants, such as compounds containing both a carboxylic acid group and a quaternary ammonium group, for example, lauryl- N , N -(Dimethyl-ammonio)-butyrate and lauryl- N , N -(Dimethyl)-glycine betaine; compounds containing both a sulfate group and a quaternary ammonium group, e.g., 3-[(3-colamido-propyl)dimethylammonio]-1-propane-sulfonate, 3-(4- tert -butyl-1-pyridinio)-1-propanesulfonate, 3-(1-pyridinio)-1-propanesulfonate and 3-(benzyl-dimethyl-ammonio)propanesulfonate; compounds containing both a phosphate group and a quaternary ammonium group, e.g., hexadecylphosphocholine; compounds containing a quaternary ammonium group to which a hydroxyl group is attached, e.g., lauryldimethylamine N -Oxide; and a phospholipid consisting of a quaternary ammonium head coupled to two hydrophobic fatty acids via a phosphate group and glycerol.

[0170] Particularly desirable surfactants are commercially available surfactants marketed under the trade names Dynol® and Zonyl®.

[0171] A preferred adhesion promoter is an organic functional silane such as 3-glycidoxypropyltrialkoxysilane, 3-amino-propyl-triethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-methacryloxypropyl-trimethoxysilane, vinyltrimethoxysilane, or octyltriethoxysilane, or a hydroxylate thereof.

[0172] Preferred crosslinking agents are melamine compounds, blocked isocyanates, functional silanes such as tetraethoxysilane, alkoxysilane hydroxylates such as tetraethoxysilane, epoxysilanes such as 3-glycidoxy-propyltrialkoxysilane.

[0173] A preferred binder is polyurethane, polyacrylate, or polyolefin.

[0174] Desirable conductivity-increasing compounds are as follows:

[0175] - Compounds containing an ether group, e.g., tetrahydrofuran;

[0176] - Compounds containing a lactone group, such as γ-butyrolactone or γ-valerolactone;

[0177] - Compounds containing amide or lactam groups, such as caprolactam, N-methylcaprolactam, N,N-dimethylacetamide, N-methylacetamide, formamide, N,N-dimethylformamide (DMF), N-methyl-formamide, N-methyl-formanilide, N-methyl-2-pyrrolidone (NMP), N-octyl-pyrrolidone, 2-pyrrolidone, N-butyl-pyrrolidone, and N-hydroxyethyl-pyrrolidone;

[0178] - Sulfonates and sulfoxides, e.g., sulfolane (tetramethylene sulfone) or dimethyl sulfoxide (DMSO);

[0179] - Sugars or sugar derivatives, e.g., arabinose, sucrose, glucose, fructose, or lactose;

[0180] - di- or polyalcohols, e.g., sorbitol, xylitol, mannitol, mannose, galactose, sorbose, gluconic acid or ethylene glycol, di- or tri(ethylene glycol), 1,1,1-trimethylol-propane, 1,3-propanediol, 1-,2-propane-diol, 1,5-pentanediol, 1,2,3-propanetriol, 1,2,4-butanetriol or 1,2,6-hexanetriol, aromatic dialcohols or polyalcohols, e.g., resorcinol.

[0181] Particularly desirable conductivity-increasing compounds are selected from the group consisting of N-methyl-pyrrolidinone, N-butyl-pyrrolidon, N-hydroxyethyl-pyrrolidon, DMSO, ethylene glycol, and diethylene glycol.

[0182] A desirable stability-improving compound is a gallic acid derivative.

[0183] The polymer capacitor formulation may have a pH of 1 to 14, more preferably 1 to 8. In the case of corrosion-sensitive dielectrics such as aluminum oxide or niobium oxide, the polymer capacitor formulation preferably has a pH of 2.5 to 8 so as not to damage the dielectric.

[0184] To adjust the pH, preferably a base or acid as described in WO2010 / 003874, page 4, lines 13 to 32 is used. These compounds do not impair film formation in polymer capacitor formulations and are not volatile at higher temperatures, such as soldering temperatures. Preferred compounds are the base 2-dimethylaminoethanol, 2,2'-iminodiethanol, or 2,2',2"-nitrilotriethanol and the acid polystyrenesulfonic acid.

[0185] The viscosity of the polymer capacitor formulation is typically optimized as a function of the application method and can be 0.01 to 1,000 mPa·s (20°C and 100 s). -1(Measured by a rheometer at the shear rate). Preferably, the viscosity is 1 to 500 mPa·s, more preferably 1 to 250 mPa·s. In the case of manufacturing an aluminum wound capacitor, the viscosity is preferably 1 to 200 mPa·s, whereas in the case of manufacturing a tantalum electrolytic capacitor or an aluminum multilayer capacitor, the viscosity is preferably 1 to 50 mPa·s.

[0186] Adjustment of viscosity can be achieved, for example, by adding a suitable rheology modifier as an additional additive.

[0187] As mentioned above, the particle size of the dispersed conductive polymer can affect the impregnation of the porous anode body. The median particle size of the polythiophene / polyanion particles (d 50 ) is preferably 1 to 150 nm, more preferably 2 to 50 nm, and most preferably 5 to 40 nm. d 50 Particle size is preferably measured by laser diffraction.

[0188] The solid content of the polymer capacitor formulation is preferably 0.01 to 20 weight%, more preferably 0.1 to 15 weight%, and most preferably 0.25 to 10 weight% based on the total weight of the formulation in each case.

[0189] Polymer capacitor

[0190] A polymer capacitor, also referred to as a polymer electrolytic capacitor, is an electrolytic capacitor containing a solid conductive polymer electrolyte.

[0191] Electrolytic capacitors utilize the chemical properties of certain special metals, often referred to as so-called valve metals, which form an insulating oxide layer through anodic oxidation. By applying a positive voltage to the anode material in an electrolytic cell, an oxide barrier layer with a thickness corresponding to the applied voltage can be formed. This oxide layer acts as a dielectric in the electrolytic capacitor. To increase the capacitor capacitance, the anode surface is roughened, and consequently, the surface of the oxide layer is also roughened.

[0192] To complete the capacitor, the counter electrode must be aligned with a rough insulating oxide surface. This is accomplished by the electrolyte acting as the cathode electrode of the electrolytic capacitor. In a polymer electrolytic capacitor, this counter electrode consists of one or more layers of a conductive polymer, preferably a polythiophene conductive polymer.

[0193] The main difference between polymer capacitors is the anode material and its oxide used as the dielectric:

[0194] - Polymer tantalum electrolytic capacitors use high-purity sintered tantalum powder as the anode while having tantalum pentoxide (Ta2O5) as the dielectric;

[0195] - Polymer aluminum electrolytic capacitors have aluminum oxide (Al2O3) as a dielectric and use high-purity electrochemically etched (rough) aluminum foil as the anode.

[0196] A porous metal layer (anode) coated with an oxide layer (dielectric) is referred to herein as a porous anode body.

[0197] Method for manufacturing a polymer capacitor

[0198] A method for manufacturing a polymer capacitor according to the present invention includes the step of introducing a polymer capacitor formulation into at least a portion of a porous anode body.

[0199] The polymer capacitor formulation can be introduced into the porous anode body by any known process such as impregnation, immersion, pouring, dropping, spraying, misting, knife coating, brushing, or printing, e.g., inkjet, screen, or tampon printing.

[0200] Preferably, the polymer capacitor formulation is introduced into at least a portion of the porous anode body by immersing the porous anode body into the polymer capacitor formulation and thus impregnating it with a liquid composition.

[0201] Immersion into the liquid composition or impregnation into the liquid composition is preferably performed for a period ranging from 1 second to 120 minutes, more preferably from 5 seconds to 60 minutes, and most preferably from 10 seconds to 15 minutes. For example, the introduction of the liquid composition into the anode body may be facilitated by increased or decreased pressure, vibration, ultrasound, or heat.

[0202] After the porous anode body is impregnated with a liquid composition, the solvent contained in the liquid composition is preferably removed at least partially to obtain a solid electrolyte that forms a capacitor body by completely or partially coating the dielectric. The coverage rate of the dielectric by the solid electrolyte is preferably at least 10%, more preferably at least 25%, and most preferably at least 50%. The coverage rate may be the same as that described in DE-A-10 2005 043 828.

[0203] The solvent is preferably removed by removing the electrode body from the liquid composition and drying it. The drying step is preferably performed at a temperature of 20°C to 260°C, more preferably 50°C to 220°C, and most preferably 80°C to 200°C.

[0204] The immersion and drying steps can be repeated one or more times to meet specific requirements for the thickness of the solid electrolyte layer deposited on the dielectric or the degree of electrolyte filling within the electrode body.

[0205] It may be advantageous to use both self-doped polythiophene and exogenously doped polythiophene for the formation of the polymer cathode layer. Both types of polythiophene polymers may be combined into a single polymer capacitor formulation and introduced as described above. However, it is preferable that both types of polythiophene be introduced into the capacitor using different polymer capacitor formulations comprising either self-doped polythiophene or exogenously doped polythiophene, respectively. Preferably, the self-doped polythiophene is introduced into the porous anode body first, followed by the introduction of the exogenously doped polythiophene. The use of both self-doped polythiophene and exogenously doped polythiophene is disclosed, for example, in WO2014 / 048562 (Heraeus) and US2016 / 0351338 (AVX).

[0206] After the capacitor bodies are manufactured in this manner, they may be further modified by methods and methods known to a person skilled in the art. In the case of tantalum electrolytic capacitors, the capacitor body may be coated with a polymer outer layer as described, for example, in DE-A-10 2004 022674 or DE-A-10 2009 007 594 and / or with a graphite layer and a silver layer as known from DE-A-10 2005 043 828, whereas in the case of aluminum wound capacitors, in accordance with the teaching of US 7,497,879 B2, the capacitor body is incorporated into an aluminum beaker, a sealing glass is provided, and the capacitor is mechanically tightly closed by crimping. Then, the capacitor may be free of dielectric defects in a manner known as aging.

[0207] Examples

[0208] ingredient

[0209] All materials used in the following examples were readily available from standard suppliers such as ALDRICH CHEMICAL Co. (Belgium) and ACROS (Belgium) unless otherwise specified. The water used was deionized water.

[0210] 4-Vinylbenzenesulfonic acid, sodium salt It was commercially available from TCI Europe (Belgium).

[0211] INI-01 is It is 2,2'-azobis[2-methyl-N-2-hydroxyethyl)propionamide] commercially available from Fujifilm (Belgium).

[0212] INI-02 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride is commercially available from Fujifilm (Belgium).

[0213] EDOT is 3,4-ethylenedioxythiophene, which is commercially available from Heraeus.

[0214] PSS-1 is a 5.85 wt% aqueous solution of polystyrenesulfonic acid having an Mw of 300 kDa prepared according to the method disclosed in the literature [Houben-Weyl, Methoden der organischen Chemie, Vol. E 20, Makromolekulaire Stoffe, Teil 2 (1987), page 1141)].

[0215] method

[0216] Viscosity measurement

[0217] Viscosity was measured using a glass capillary viscometer.

[0218] Surface resistance measurement

[0219] Surface resistance SER was measured at room temperature using the two-point probe method.

[0220] Particle size measurement

[0221] The median particle size was determined by laser diffraction analysis on a Malvern-Panalytical Mastersizer 3000.

[0222] Molecular weight measurement

[0223] The molecular weight of the polymer was determined by gel permeation chromatography (GPC) on a Waters e2695 Alliance equipped with a 2998A PDA detector, calibrated with a polystyrene sulfonate standard. The molecular weight distribution was calculated using Waters Empower 3.

[0224] Nuclear magnetic resonance measurement

[0225] The molar ratios of the copolymer were determined by nuclear magnetic resonance (NMR) on a JEOL ECZ400R with a Royal probe in D2O (at = 2.04" - d1 = 10" - nt = 64 - 25 gr C - pw45).

[0226] Capacitance measurement

[0227] The capacitance of the capacitor was measured at 120 Hz at room temperature using a potentiostat.

[0228] ESR measurement

[0229] The equivalent series resistance (ESR) was measured at 100 kHz at room temperature using a potentiostat.

[0230] Example 1

[0231] Synthesis of monomer I-2 ((4-vinylphenyl)methanesulfonate, sodium salt)

[0232]

[0233] Sodium sulfite (22.72 g, 180 mmol) and 2,6-di- tert 0.79 g, 4 mmol of methylphenol (butyl-4-methylphenol) was dissolved in 144 mL of water under nitrogen blanketing. A solution of 1-(chloromethyl)-4-vinyl-benzene (20.35 g, 120 mmol) in acetone (114 mL) was added to the stirred reaction mixture. Next, the reaction mixture was refluxed for 6 hours. Afterward, the reaction mixture was cooled to room temperature. The formed precipitate was filtered and washed with ethanol. The filtrate was concentrated under vacuum.

[0234] Both fractions were recrystallized in water / isopropanol (0.75 / 0.25), filtered, and washed with acetone to obtain (4-vinylphenyl)methanesulfonate, sodium salt (23.4 g, 88.6%) as a white powder.

[0235] Synthesis of (1-(2-bromoalkyl)-4-ethenylbenzene) intermediates 03 to 05

[0236]

[0237] 4-bromostyrene (7.32 g, 40.0 mmol, 1 eq.) was dissolved in THF (133 mL) and stirred under a nitrogen atmosphere. The solution was cooled to -70°C, and n- Butyllithium (2.5 M in hexane, 16.80 mL, 42.0 mmol) was added dropwise. After stirring for 1 hour, the dibromoalkane reagents as shown in Table 4 below were added (4 eq.), and the stirred reaction mixture was heated to room temperature. The reaction mixture was stirred for an additional 2 hours. Subsequently, water was added (50 mL), and THF was removed by rotary evaporation. The mixture was extracted with dichloromethane (2 x 50 mL). Then, butylhydroxytoluene (BHT, 0.09 g, 0.01 eq.) was added to the organic phase, washed with brine (50 mL), dried using magnesium sulfate, and filtered. The remaining dichloromethane was removed by rotary evaporation.

[0238] The obtained mixture is column chromatographed ( n It was purified with hexane / dichloromethane. The product was obtained as a grayish-white solid. The exact amount of dibromoalkane reagent and the reaction yield after purification can be confirmed in Table 4 below.

[0239] Table 4

[0240]

[0241] Synthesis of ((4-vinylphenyl)alkane-sulfonate, sodium salt) monomers I-3 to I-5

[0242]

[0243] Na2SO3 and BHT were dissolved in water under nitrogen blanketing. A solution of intermediate-O3 in acetone was added to the stirred reaction mixture. Next, the reaction mixture was refluxed for 6 hours. Afterward, the reaction mixture was cooled to room temperature. The formed precipitate was filtered and washed with ethanol. In this way, monomer I-3 was obtained as a white powder. The exact amounts used in the reaction and the reaction yield after purification can be found in Table 5 below.

[0244] For monomer I-4, a solution of intermediate-04 in acetone was used, and the filtrate obtained after washing with ethanol was dried by rotary evaporation. Next, the resulting residue was treated with methyl-tert-butyl ether, filtered, and dried.

[0245] For monomer I-5, a solution of intermediate-05 in acetone was used, and the filtrate obtained after washing with ethanol was dried by rotary evaporation. Next, the resulting residue was treated with methyl-tert-butyl ether, filtered, and dried.

[0246]

[0247]

[0248] Example 2

[0249] Preparation of polyanion-01 (a) to polyanion-01 (g) (where X = 1 and Y = 0)

[0250]

[0251] Polyanion-01 (a)

[0252] 3.89 g of monomer I-2 (4-vinylphenyl)methanesulfonate, sodium salt obtained in Example 1 was dissolved in 77.73 mL of water. The reaction mixture was stirred and heated to 90°C.

[0253] A 2 wt% solution of INI-01 in water was prepared and degassed with nitrogen for 1 hour. The amount of the initiator solution was rapidly added to the reaction mixture to achieve an initiator concentration of 3.33 mol%. The solution was stirred at 90°C for 20 hours.

[0254] Next, the reaction mixture was treated twice with an ion exchanger (30 g Lewatit® MonoPlus S 108 H, filtered and washed with 2 x 20 mL water).

[0255] This process produced a clear to slightly yellow solution of polyanion-01 (a) (where x = 1) in water.

[0256] Polyanion-01 (b)

[0257] Polyanion-01 (b) was synthesized using 10.55 g of monomer I-2 and 73.05 mL of water as described for polyanion-01 (a).

[0258] Polyanion-01 (c)

[0259] Polyanion-01 (c) was synthesized using 5.22 g of monomer I-2 and 30.92 mL of water as described in Polyanion-01 (a).

[0260] Polyanion-01 (d)

[0261] Polyanion-01 (d) was synthesized as described in Polyanion-01 (a) using a 2 wt% solution of INI-02, 4.00 g of monomer I-2, 22.62 mL of water, and a reaction temperature of 60°C.

[0262] Polyanion-01 (e)

[0263] Polyanion-01 (e) was synthesized as described in Polyanion-01 (a) using an initiator concentration of 2.00 mol%, 5.22 g of monomer I-2, and 35.46 mL of water.

[0264] Polyanion-01 (f)

[0265] Polyanion-01 (f) was synthesized using 5.22 g of monomer I-2 and 30.92 mL of water as described in Polyanion-01 (a).

[0266] Polyanion-01 (g)

[0267] Polyanion-01 (g) was synthesized as described in Polyanion-01 (a) using a 3.33 mol% solution of INI-02, 10.00 g of monomer I-2, and 56.56 mL of water.

[0268] Example 3

[0269] Preparation of polyanion-01 (h) to polyanion-01 (j) having variable X and Y

[0270]

[0271] Polyanion-01 (h)

[0272] 5.77 g of 4-vinylbenzenesulfonic acid, sodium salt and 2.05 g of monomer I-2 ((4-vinylphenyl)methanesulfonate, sodium salt) obtained in Example 1 were dissolved in 45.10 mL of water. The reaction mixture was stirred and heated to 90°C.

[0273] A 2 wt% solution of INI-01 in water was prepared and degassed with nitrogen for 1 hour. The amount of the initiator solution was rapidly added to the reaction mixture to achieve an initiator concentration of 3.33 mol%. The solution was stirred at 90°C for 20 hours.

[0274] Next, the reaction mixture was treated twice with an ion exchanger (50 g Lewatit® MonoPlus S 108 H, filtered and washed with 2 x 50 mL water).

[0275] This process produced a clear to slightly yellow solution of polyanion-01 (h) in water.

[0276] Polyanion-01 (i)

[0277] Polyanion-01 (i) was synthesized as described in Polyanion-01 (h) using 3.77 g of 4-vinylbenzenesulfonic acid, sodium salt, 4.03 g of monomer I-2, and 45.43 mL of water.

[0278] Polyanion-01 (j)

[0279] Polyanion-01 (j) was synthesized as described in Polyanion-01 (h) using 4-vinylbenzenesulfonic acid, 1.85 g of sodium salt, 5.94 g of monomer I-2, and 45.74 mL of water.

[0280] Example 4

[0281] Preparation of polyanion-02 to polyanion-04

[0282]

[0283] Polyanion-02

[0284] 1.43 g of monomer I-3 obtained in Example 1 was dissolved in 8.94 mL of water. The reaction mixture was stirred and heated to 95°C.

[0285] A 2 wt% solution of INI-01 in water was prepared and degassed with nitrogen for 1 hour. The amount of the initiator solution was rapidly added to the reaction mixture to achieve an initiator concentration of 3.33 mol%. The solution was stirred at 90°C for 20 hours.

[0286] Next, the reaction mixture was diluted with water (25 mL) and treated twice with an ion exchanger (10 g Lewatit® MonoPlus S 108 H, filtered and washed with 2 x 10 mL water).

[0287] This process produced a clear to slightly yellowish solution of polyanion-O2 in water.

[0288] Polyanion-03

[0289] 0.82 g of monomer I-4 obtained in Example 1 was dissolved in 5.25 mL of water. The reaction mixture was stirred and heated to 95°C.

[0290] A 2 wt% solution of INI-01 in water was prepared and degassed with nitrogen for 1 hour. The amount of the initiator solution was rapidly added to the reaction mixture to achieve an initiator concentration of 3.33 mol%. The solution was stirred at 90°C for 20 hours.

[0291] Next, the reaction mixture was diluted with water (25 mL) and treated twice with an ion exchanger (10 g Lewatit® MonoPlus S 108 H, filtered and washed with 2 x 10 mL water).

[0292] This process produced a clear to slightly yellowish solution of polyanion-03 in water.

[0293] Polyanion-04

[0294] 1.11 g of monomer I-5 obtained in Example 1 was dissolved in 8.07 mL of water. The reaction mixture was stirred and heated to 95°C.

[0295] A 2 wt% solution of INI-01 in water was prepared and degassed with nitrogen for 1 hour. The amount of the initiator solution was rapidly added to the reaction mixture to achieve an initiator concentration of 3.33 mol%. The solution was stirred at 90°C for 20 hours.

[0296] Next, the reaction mixture was treated twice with an ion exchanger (10 g Lewatit® MonoPlus S 108 H, filtered and washed 2 times with 15 mL of water).

[0297] This process produced a clear to slightly yellowish solution of polyanion-04 in water.

[0298] Example 5

[0299] The molecular weights (Mw) in kDa units of polyanion-01 (a) to polyanion-01 (j), polyanion-02, polyanion-03, and polyanion-04 were determined as described above. The results are 1 The X / Y ratio measured by H-NMR and the concentration of the obtained polyanion solution are shown in Table 6 below.

[0300] Table 6

[0301]

[0302] Example 6

[0303] Preparation of PEDOT / Polyanion-01 (a) dispersion

[0304]

[0305] 77.3 g of the aqueous solution of polyanion-01 (a) obtained in Example 2, deionized water (147 mL), and nitric acid (2.4 g, 2.72 mmol) were mixed in a reaction vessel. Iron(III) sulfate (0.09 g, 0.22 mmol) and sodium persulfate (1.78 g, 7.47 mmol) were added. The reaction mixture was stirred and cooled to 5°C under a nitrogen flow for 90 minutes. The oxygen level was less than 30 ppb. 3,4-ethylenedioxythiophene (EDOT) (0.96 g, 6.79 mmol) was added to the reaction mixture and stirred at 5°C under nitrogen for 20 hours. The reaction mixture was treated with an ion exchanger (65 g Lewatit® MonoPlus M600 + 35 g Lewatit® MonoPlus S 108 H, filtered, washed 3 times with 25 mL of water, and repeated). The resulting viscous mixture was treated with high-shear homogenization (Lab Gaulin, 4 times 600 bar). The dispersion was concentrated under vacuum. This process produced a blue dispersion (1.38 wt%) of PEDOT / polyanion-01 (a) in water.

[0306] Example 7

[0307] Preparation of PEDOT / Polyanion-01 (b) dispersion

[0308] Polymerization was carried out in the same manner as in Example 6, except that 88.7 g of polyanion-01 (b) obtained in Example 2, 210 mL of deionized water, 3.1 g of nitric acid, 0.11 g of iron(III) sulfate, 2.26 g of sodium persulfate, and 1.23 g of EDOT were used. The reaction mixture was treated with an ion exchanger (77 g Lewatit® MonoPlus M600 + 42 g Lewatit® MonoPlus S 108 H, filtered, washed 3 times with 30 mL of water, and repeated). This process produced a blue dispersion (1.15 wt%) of PEDOT:polyanion-01 (b) in water.

[0309] Example 8

[0310] Preparation of PEDOT / Polyanion-01 (c) dispersion

[0311] Polymerization was carried out in the same manner as in Example 6, except that 172.8 g of polyanion-01 (c) obtained in Example 2, 206 mL of deionized water, 3.9 g of nitric acid, 0.14 g of iron(III) sulfate, 2.86 g of sodium persulfate, and 1.55 g of EDOT were used. The reaction mixture was treated with an ion exchanger (100 g Lewatit® MonoPlus M600 + 55 g Lewatit® MonoPlus S 108 H, filtered, washed with 2 x 50 mL of water, and repeated). This process produced a blue dispersion (1.28 wt%) of PEDOT / polyanion-01 (c) in water.

[0312] Example 9

[0313] Preparation of PEDOT / Polyanion-01 (d)

[0314] Polymerization was carried out in the same manner as in Example 6, except that 83.2 g of polyanion-01 (d) obtained in Example 2, 176 mL of deionized water, 2.70 g of nitric acid, 0.10 g of iron(III) sulfate, 1.96 g of sodium persulfate, and 1.06 g of EDOT were used. The reaction mixture was treated with an ion exchanger (70 g Lewatit® MonoPlus M600 + 40 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 50 mL of water, and repeated). This process produced a blue dispersion (1.27 wt%) of PEDOT / polyanion-01 (d) in water.

[0315] Example 10

[0316] Preparation of PEDOT / Polyanion-01 (e)

[0317] Polymerization was carried out in the same manner as in Example 6, except that 191.7 g of polyanion-01 (e) obtained in Example 2, 197 mL of deionized water, 4.0 g of nitric acid, 0.15 g of iron(III) sulfate, 2.94 g of sodium persulfate, and 1.59 g of EDOT were used. The reaction mixture was treated with an ion exchanger (100 g Lewatit® MonoPlus M600 + 55 g Lewatit® MonoPlus S 108 H, filtered, washed with 2 x 50 mL of water, and repeated). This process produced a blue dispersion (1.23 wt%) of PEDOT / polyanion-01 (e) in water.

[0318] Example 11

[0319] Preparation of PEDOT / Polyanion-01 (f)

[0320] Polymerization was carried out in the same manner as in Example 6, except that 131.9 g of polyanion-01 (f) obtained in Example 2, 346 mL of deionized water, 5.0 g of nitric acid, 0.18 g of iron(III) sulfate, 3.62 g of sodium persulfate, and 1.96 g of EDOT were used. The reaction mixture was treated with an ion exchanger (125 g Lewatit® MonoPlus M600 + 66 g Lewatit® MonoPlus S 108 H, filtered, washed with 2 x 50 mL of water, and repeated). This process produced a blue dispersion (1.40 wt%) of PEDOT / polyanion-01 (f) in water.

[0321] Example 12

[0322] Preparation of PEDOT / Polyanion-01 (g)

[0323] Polymerization was carried out in the same manner as in Example 6, except that 134.9 g of polyanion-01 (g) obtained in Example 2, 323 mL of deionized water, 4.8 g of nitric acid, 0.17 g of iron(III) sulfate, 3.47 g of sodium persulfate, and 1.88 g of EDOT were used. The reaction mixture was treated with an ion exchanger (120 g Lewatit® MonoPlus M600 + 65 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 50 mL of water, and repeated). This process produced a blue dispersion (1.22 wt%) of PEDOT / polyanion-01 (g) in water.

[0324] Example 13

[0325] Preparation of PEDOT / Polyanion-01 (h)

[0326] Polymerization was carried out in the same manner as in Example 6, except that 110.8 g of polyanion-01 (h) obtained in Example 3, 213 mL of deionized water, 3.48 g of nitric acid, 0.12 g of iron(III) sulfate, 2.53 g of sodium persulfate, and 1.37 g of EDOT were used. The reaction mixture was treated with an ion exchanger (90 g Lewatit® MonoPlus M600 + 50 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 50 mL of water, and repeated). This process produced a blue dispersion (1.23 wt%) of PEDOT / polyanion-01 (h) in water.

[0327] Example 14

[0328] Preparation of PEDOT / Polyanion-01 (i)

[0329] Polymerization was carried out in the same manner as in Example 6, except that 125.7 g of polyanion-01 (i) obtained in Example 3, 198 mL of deionized water, 3.43 g of nitric acid, 0.12 g of iron(III) sulfate, 2.50 g of sodium persulfate, and 1.35 g of EDOT were used. The reaction mixture was treated with an ion exchanger (90 g Lewatit® MonoPlus M600 + 50 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 50 mL of water, and repeated). This process produced a blue dispersion (1.38 wt%) of PEDOT / polyanion-01 (i) in water.

[0330] Example 15

[0331] Preparation of PEDOT / Polyanion-01 (j)

[0332] Polymerization was carried out in the same manner as in Example 6, except that 119.2 g of polyanion-01 (j) obtained in Example 3, 205 mL of deionized water, 3.39 g of nitric acid, 0.12 g of iron(III) sulfate, 2.46 g of sodium persulfate, and 1.34 g of EDOT were used. The reaction mixture was treated with an ion exchanger (90 g Lewatit® MonoPlus M600 + 45 g Lewatit® MonoPlus S 108 H, filtered, washed with 2 x 50 mL of water, and repeated). This process produced a blue dispersion (1.32 wt%) of PEDOT / polyanion-01 (j) in water.

[0333] Example 16

[0334] Preparation of PEDOT / Polyanion-O2

[0335] Polymerization was carried out in the same manner as in Example 6, except that 22.6 g of polyanion-02 obtained in Example 4, 14.8 mL of deionized water, 0.35 g of nitric acid, 0.013 g of iron(III) sulfate, 0.25 g of sodium persulfate, and 0.14 g of EDOT were used. The reaction mixture was treated with an ion exchanger (10 g Lewatit® MonoPlus M600 + 5 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 15 mL of water, and repeated). This process produced a blue dispersion (1.00 wt%) of PEDOT / polyanion-02 in water.

[0336] Example 17

[0337] Preparation of PEDOT / Polyanion-O3

[0338] Polymerization was carried out in the same manner as in Example 6, except that 24.3 g of polyanion-03 obtained in Example 4, 13.6 mL of deionized water, 0.34 g of nitric acid, 0.012 g of iron(III) sulfate, 0.25 g of sodium persulfate, and 0.13 g of EDOT were used. The reaction mixture was treated with an ion exchanger (10 g Lewatit® MonoPlus M600 + 5 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 15 mL of water, and repeated). This process produced a blue dispersion (1.32 wt%) of PEDOT / polyanion-03 in water.

[0339] Example 18

[0340] Preparation of PEDOT / Polyanion-04

[0341] Polymerization was carried out in the same manner as in Example 6, except that 46.6 g of polyanion-04 obtained in Example 4, 8.2 mL of deionized water, 0.45 g of nitric acid, 0.016 g of iron(III) sulfate, 0.33 g of sodium persulfate, and 0.18 g of EDOT were used. The reaction mixture was treated with an ion exchanger (12 g Lewatit® MonoPlus M600 + 6 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 15 mL of water, and repeated). This process produced a blue dispersion (1.90 wt%) of PEDOT / polyanion-04 in water.

[0342] Comparative Example 1: Preparation of PEDOT / PSS-1

[0343] 73.3 g of PSS-1, deionized water (325 mL), and nitric acid (4.3 g, 48.3 mmol) were mixed in a reaction vessel.

[0344] Iron(III) sulfate (0.16 g, 0.39 mmol) and sodium persulfate (3.16 g, 13.3 mmol) were added. The reaction mixture was stirred and cooled to 5°C under a nitrogen flow. The oxygen level was less than 30 ppb.

[0345] EDOT (1.71 g, 12.1 mmol) was added to the reaction mixture and stirred at 5°C for 20 hours.

[0346] Next, the reaction mixture was treated with an ion exchanger (110 g Lewatit® MonoPlus M600 + 60 g Lewatit® MonoPlus S 108 H, filtered, washed twice with 50 mL water, and repeated). The resulting viscous mixture was treated with high-shear homogenization (Lab Gaulin, 4 x 600 bar).

[0347] After a concentration step under vacuum, a blue dispersion of 1.12 wt% of PEDOT / PSS-1 (a) in water was obtained.

[0348] Comparative Example 2: Preparation of PEDOT / PSS-1

[0349] Polymerization was carried out in the same manner as in Comparative Example 1. This process produced a blue dispersion (1.22 wt%) of PEDOT / PSS-1 (b) in water, and the pH level was adjusted to 3.16 using 2-dimethyl-amino-ethanol.

[0350] Comparative Example 3: Preparation of PEDOT / PSS-1

[0351] Polymerization was carried out in the same manner as in Comparative Example 1 using 2.06 g of EDOT, 88.7 g of PSS-1, 389 mL of deionized water, 14.3 g of nitric acid, 0.094 g of iron(III) sulfate, 3.48 g of sodium persulfate, 130 g of Lewatit® MonoPlus M600, and 70 g of Lewatit® MonoPlus S 108 H. This process produced a blue dispersion (1.15 wt%) of PEDOT / PSS-1(c) in water.

[0352] Example 19

[0353] The particle size (Φ) of the dispersions according to Table 7 below and the SER of the bar-coated films of these dispersions on PET are shown in Table 7 below.

[0354] Table 7

[0355]

[0356] From Table 7, it is evident that the particle size of the PEDOT dispersion containing polyanions according to the present invention is comparable to the particle size of conventional PEDOT / PSS dispersions. This also applies to the SER of coatings from these dispersions, with the exception of polyanions-02, 03, and 04, which have not been further studied.

[0357] Example 20

[0358] A polymer dispersion according to Table 8 below was bar-coated onto a PET substrate. Subsequently, the coated films were stored for 500 hours at 60°C / 95% RH, 85°C / 85% RH, and 105°C / dry. The SER ratio (ΔSER(hour)) of the new films and the stored films is given in Table 8 below.

[0359] Table 8

[0360]

[0361] From the results in Table 8, it is evident that the film prepared from the dispersion using the polyanion according to the present invention is more stable when stored under high temperature / high relative humidity (RH) conditions.

[0362] Example 21

[0363] pH studies were performed, in which the pH was changed from the starting pH of the dispersion to a pH level of 4 to 6 (final pH mentioned in Table 9 below) using 2-dimethylamino-ethanol. At both the starting and ending pHs, the median particle size in the dispersion was measured, a conductive layer was prepared on PET using a bar coater, and its SER was measured.

[0364] Table 9 below shows the ratio of the median particle size of the dispersion at the end pH to the median particle size of the dispersion at the start pH [Φ pH (end) / Φ pH (start)].

[0365] Table 9 below also shows the SER ratio (ΔSER (pH)) of the coated layer of the dispersion at both the starting pH and the ending pH.

[0366] Table 9

[0367]

[0368] From the results in Table 9, it is clear that the dispersion using the polyanion according to the present invention is more stable as a function of increasing pH compared to the conventional PEDOT / PSS dispersion.

[0369] Example 22: Manufacture of a capacitor

[0370] A chemically modified aluminum foil containing an etched layer on its surface was prepared as a valve metal base. A dielectric layer was formed to coat the aluminum foil. The resulting chemically modified aluminum foil was used as an anode component. The rated voltage of the alumina layer is 90 V, and the capacitance is 6.4 μF / cm². 2 A solder mask with a thickness of 20 μm was printed on an Al foil with an array of 10 mm x 10 mm openings. The patterned foil was cut into a 30 mm x 105 mm strip having five openings on it.

[0371] The conductive polymer dispersion used in the manufacture of the capacitor was formulated using water, diethylene glycol, and DYNOL™ 604 and treated with an ultrasonic homogenization step before coating on aluminum foil.

[0372] Next, the strip was dip-coated with a PEDOT / polyanion-01 (e) dispersion and dried at 150°C for 5 minutes. The dip coating and curing steps were repeated several times. Subsequently, carbon paste and silver paste were sequentially screen-printed onto the PEDOT layer and cured.

[0373] When PEDOT / polyanion-01 (f), PEDOT / polyanion-01 (g), and PEDOT / PSS-1 (c) were used as conductive polymer dispersions, additional capacitors were manufactured and measured as described above.

[0374] The results of the capacitor evaluation are summarized in Table 10 below.

[0375]

[0376]

[0377] From the results in Table 10, it is clear that the dispersion using the polyanion according to the present invention has a higher capacitor capacitance, while the ESR is lower.

Claims

Claim 1 A conductive polymer dispersion comprising polythiophene and a polyanion, wherein the polyanion is a homopolymer or copolymer of a monomer according to the following chemical formula I: <Chemical Formula I> In the above formula, any one of R1 to R5 is selected from the group consisting of hydrogen, halogen, ether, and substituted or unsubstituted alkyl groups, provided that at least one of R1 to R5 is a substituent according to the following formula II; <Formula II> In the above formula, L represents a divalent linker having fewer than 20 carbon atoms; n represents 0 or 1; R6 and R7 are independently selected from the group consisting of hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted alkynyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted alkaryl group, and a substituted or unsubstituted aryl or heteroaryl group; any of L, R6 and R7 may represent atoms necessary to form a 5- to 8-membered ring; M represents a hydrogen or counterion to compensate for the negative charge of the sulfonate group; and the dashed line represents a covalent bond to the phenyl ring of formula I. Claim 2 In paragraph 1, C1 to C in which L is substituted or unsubstituted 10 Alkylene-derived conductive polymer dispersion. Claim 3 A conductive polymer dispersion according to claim 1, wherein n is 0. Claim 4 A conductive polymer dispersion in which R6 and R7 are hydrogen, as in claim 1. Claim 5 A conductive polymer dispersion according to claim 1, wherein only one of R2, R3 and R4 is a substituent represented by Chemical Formula II. Claim 6 A conductive polymer dispersion according to claim 1, wherein R3 is a substituent represented by Chemical Formula II, and R1, R2, R4 and R5 represent hydrogen. Claim 7 In paragraph 1, M is H + or Na + A conductive polymer dispersion representing Claim 8 In claim 1, the polythiophene and the polyanion have a median particle size (d) measured by laser diffraction. 50 A conductive polymer dispersion existing as polythiophene / polyanion particles having a length of 5 to 40 nm. Claim 9 A liquid formulation comprising a conductive polymer dispersion according to claim 1. Claim 10 In claim 9, the liquid formulation has a pH of 2 to 8.

5. Claim 11 In claim 9, the viscosity of the liquid formulation is 20°C and 100 s -1 A liquid formulation having a shear rate of 1 to 250 mPa·s as measured by a rheometer. Claim 12 A liquid formulation according to claim 9, further comprising a conductivity-increasing compound selected from the group consisting of N-methyl-pyrrolidinone, N-butyl-pyrrolidon, N-hydroxyethyl-pyrrolidon, DMSO, ethylene glycol, and diethylene glycol. Claim 13 A method for manufacturing a polymer capacitor comprising a porous anode body, comprising the step of introducing a liquid formulation according to claim 9 into at least a portion of the porous anode body. Claim 14 In claim 9, the liquid formulation is a liquid formulation used for manufacturing a conductive layer in an electronic device. Claim 15 A liquid formulation according to claim 14, wherein the electronic device is selected from a photoconductive cell, photoresistor, optical switch, phototransistor, phototube, IR detector, photovoltaic device, solar cell, coating material for memory storage device, field effect resistor device, antistatic film, biosensor, electrochromic device, solid electrolyte capacitor, hybrid capacitor, supercapacitor, energy storage device, battery, and electromagnetic shielding.

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