Conductive polymer monomer composition, conductive polymer and electrolytic capacitor

Abstract

In order to solve the problem that existing benzodifuran diketone and derivatives thereof cannot be applied to capacitors, the invention provides a conductive polymer monomer composition, which comprises the following components: a polymeric monomer, a polymer with a polyoxyethylene repetitive unit and a solvent, the polymeric monomer comprises a compound as shown in a structural formula 1; wherein R1 and R2 are independently selected from-O-,-S-or # imgabs 1 #, and R3 is selected from a hydrogen atom, an alkyl group of C1 to C18, an alkylene group of C1 to C18, an alkyl derivative of C1 to C18 or an alkylene derivative of C1 to C18. Meanwhile, the invention also discloses a conductive polymer comprising the conductive polymer monomer composition and an electrolytic capacitor. According to the conductive polymer monomer composition provided by the invention, the polymer with a polyoxyethylene repetitive unit is added, so that the capacity of a polymeric monomer entering medium pores and the continuous film forming capacity can be improved, and the contact surface area of the polymeric monomer and polymerized macromolecules with a medium layer is promoted, so that the capacity extraction is improved, and the ESR is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of capacitor materials, and in particular relates to a conductive high molecular monomer composition, a conductive polymer and an electrolytic capacitor. Background Art

[0002] As one of the three major passive components, capacitors play an irreplaceable role in the electrical and electronic industry and electrical equipment. With the development of the industry, in addition to the long-term reliability required of capacitors, more and higher requirements are also put forward for capacitors. For example, electrical equipment that operates at high frequencies, such as servers and computer hosts, requires capacitors to have small size and lower ESR (equivalent series resistance); fast charging plugs require higher voltage resistance and stable charging and discharging performance; base stations and outdoor electrical equipment require electrolytic capacitors to have stable and reliable performance under extreme high and low temperatures; large-capacity capacitors with both energy storage and current supplement functions have requirements for losses. In the past 20 years, conductive polymer-based electrolytic capacitors have made outstanding progress in high-frequency equivalent series resistance. At the same time, the application end mentioned above also puts forward new requirements for the performance of electrolytic capacitors. As the actual cathode material of electrolytic capacitors, the intrinsic conductivity and processing technology of conductive polymers are the core factors that determine the performance of electrolytic capacitors.

[0003] The conductivity of the conductive polymer, the combination of the conductive polymer and the components of the capacitor, and the filling of the conductive polymer in the capacitor have an important impact on the performance and reliability of the capacitor. 3+ Conductive polymers are synthesized in situ in capacitors. A strong oxygen catalyst is used in the polymerization process of the polymer, and acid is generated after polymerization. The generated acid and residual salt will have a lasting impact on the life of the capacitor, mainly because the acidic substances or metal salts damage other module structures of the capacitor, such as metal dielectrics. There is a conjugated polymer based on benzodifurandione and its derivatives, which has the characteristics of high conductivity and no strong oxidizing and acidic substances remain after polymerization. However, during the preparation of this polymer, when the conductive polymer monomer is used for the impregnation operation of the capacitor element, it is difficult to fully penetrate into the interior of the capacitor element, thereby affecting the capacity of the capacitor, and the equivalent series resistance of the resulting capacitor is relatively high. Summary of the invention

[0004] In view of the problem that existing benzodifurandione and its derivatives are effectively applicable to capacitors, the present invention provides a conductive polymer monomer composition and an electrolytic capacitor.

[0005] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0006] In one aspect, the present invention provides a conductive polymer monomer composition, comprising the following components:

[0007] A polymerizable monomer, a polymer having a polyoxyethylene repeating unit and a solvent, wherein the polymerizable monomer comprises a compound represented by structural formula 1;

[0008]

[0009] Wherein, R1 and R2 are each independently selected from -O-, -S- or Wherein R3 is selected from a hydrogen atom, a C1-C18 alkyl group, a C1-C18 alkylene group, a C1-C18 alkyl derivative or a C1-C18 alkylene derivative.

[0010] Optionally, the polymer having polyoxyethylene repeating units is selected from polyoxyethylene ethers terminated with an alkyl group or an alkyl substituent.

[0011] Optionally, the polymer having polyoxyethylene repeating units is selected from one or more polyoxyethylene ether derivatives having an alkyl or alkyl substituent end capped at one end and a sulfated, carboxylated, sulfonated or phosphated anionic structure functionalized at the other end.

[0012] Optionally, the polymer having polyoxyethylene repeating units includes a compound shown in structural formula 2:

[0013]

[0014] Wherein, n=2-15; molecular weight is 200-1000;

[0015] R4 is selected from C4 to C20 substituents having 1 to 4 methyl groups.

[0016] R5 is selected from H, a C1-C6 substituent having a sulfonic acid group, a sulfate ester group, a sulfuric acid group or a carbonyl structure.

[0017] Optionally, R5 is selected from C1-C6 substituents having a sulfonic acid group, a sulfate ester group, a sulfuric acid group or a carbonyl structure.

[0018] Optionally, the polymer having polyoxyethylene repeating units includes one or more of isomeric decanol polyoxyethylene ether, fatty alcohol polyoxyethylene sodium sulfate, fatty alcohol polyoxyethylene ether ammonium sulfate, fatty alcohol polyoxyethylene sulfosuccinate disodium salt, dodecyl polyoxyethylene ether sulfate triethanolamine, fatty acid polyoxyethylene ether sodium carboxylate, fatty acid polyoxyethylene ether sodium sulfonate, and isomeric decanol polyoxyethylene ether phosphate.

[0019] Optionally, based on the total mass of the conductive polymer monomer composition being 100%, the mass proportion of the polymer having polyoxyethylene repeating units is 0.1% to 20%.

[0020] Optionally, based on the total mass of the conductive polymer monomer composition being 100%, the mass proportion of the polymerized monomer is 3% to 35%.

[0021] Optionally, the solvent includes one or more of water, alcohol solvents, ether solvents, sulfone solvents, amide solvents, imide solvents, ketone solvents, lipid solvents, aromatic solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, and aromatic hydrocarbon solvents. Based on the total mass of the conductive polymer monomer composition as 100%, the mass proportion of the solvent is 45 to 96.9%.

[0022] In another aspect, the present invention provides a conductive polymer, which is prepared by combining the conductive polymer monomer composition as described above with an oxidant.

[0023] Optionally, the molar ratio of the polymerizable monomer to the oxidant is (0.2-6):1, and the oxidant includes one or more of a peroxide structure, a persulfate structure, a perboric acid structure, and an aromatic quinone structure.

[0024] On the other hand, the present invention provides an electrolytic capacitor, comprising an anode foil having a dielectric layer on its surface, a cathode foil, an electrolytic paper arranged between the anode foil and the cathode foil, and a conductive polymer as described above in contact with the dielectric layer or a conductive polymer prepared from the conductive high molecular monomer composition as described above.

[0025] According to the conductive polymer monomer composition provided by the present invention, the compound shown in structural formula 1 is used as a polymerized monomer. The conductive polymer obtained by polymerizing the polymer monomer has the characteristics of high conductivity, and the conductivity exceeds 1000S / cm, which can reduce the resistance of the electrolytic capacitor to a certain extent, and no additional acidic catalyst or alkaline catalyst is required during the polymerization process, which can reduce the damage of the in-situ generated conductive polymer to the dielectric layer, thereby improving the withstand voltage, leakage current, stability and reliability of the electrolytic capacitor; in order to solve the problem of insufficient permeability of the polymer monomer to the dielectric layer of the electrolytic capacitor, a polymer having a polyoxyethylene repeating unit is added to the conductive polymer monomer composition, and the polymer can promote the spreading and penetration of the compound shown in structural formula 1 on the surface of the dielectric layer, improve the ability of the polymer monomer to enter the pores of the dielectric, and promote the surface area of ​​the polymer monomer and the polymerized polymer in contact with the dielectric layer, thereby increasing the capacity extraction. Further, the polymer having a polyoxyethylene repeating unit can give the polymerized polymer a continuous film-forming function, thereby reducing ESR (equivalent series resistance). BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Embodiment 1 of the present invention provides an electrolyte interface diagram after the capacitor is disassembled;

[0027] Figure 2 The comparative example 1 of the present invention provides an electrolyte interface diagram after the capacitor is disassembled. DETAILED DESCRIPTION

[0028] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0029] An embodiment of the present invention provides a conductive polymer monomer composition, comprising the following components:

[0030] A polymerizable monomer, a polymer having a polyoxyethylene repeating unit and a solvent, wherein the polymerizable monomer comprises a compound represented by structural formula 1;

[0031]

[0032] Wherein, R1 and R2 are each independently selected from -O-, -S- or Wherein R3 is selected from a hydrogen atom, a C1-C18 alkyl group, a C1-C18 alkylene group, a C1-C18 alkyl derivative or a C1-C18 alkylene derivative.

[0033] In the description of the present invention, the term "alkylene" refers to unsaturated hydrocarbon groups such as alkenyl and alkynyl. The term "alkyl derivative" refers to single or multiple hydrogens on the alkyl group replaced by other groups, and the term "alkylene derivative" refers to single or multiple hydrogens on the alkyl group replaced by other groups, and the other groups can be halogens, halogenated hydrocarbons, oxygen-containing groups, nitrogen-containing groups, etc.

[0034] The conductive polymer monomer composition adopts the compound shown in structural formula 1 as a polymerization monomer. The conductive polymer obtained by polymerization of the polymer monomer has the characteristics of high conductivity, and the conductivity exceeds 1000S / cm, which can reduce the resistance of the electrolytic capacitor to a certain extent. In addition, no additional acidic catalyst or alkaline catalyst is required during the polymerization process, which can reduce the damage of the in-situ generated conductive polymer to the dielectric layer, thereby improving the withstand voltage, leakage current, stability and reliability of the electrolytic capacitor. In order to solve the problem of insufficient permeability of the polymer monomer to the dielectric layer of the electrolytic capacitor, a polymer having polyoxyethylene repeating units is added to the conductive polymer monomer composition. The polymer can promote the spreading and penetration of the compound shown in structural formula 1 on the surface of the dielectric layer, improve the ability of the polymer monomer to enter the pores of the dielectric, and promote the surface area of ​​the polymer monomer and the polymerized polymer in contact with the dielectric layer, thereby improving the capacity extraction.

[0035] In some embodiments, the polymer having polyoxyethylene repeating units is selected from polyoxyethylene ethers terminated with an alkyl group or an alkyl substituent.

[0036] In a preferred embodiment, the polymer having polyoxyethylene repeating units is selected from one or more polyoxyethylene ether derivatives having an alkyl or alkyl substituent end capped at one end and a sulfated, carboxylated, sulfonated, or phosphated anionic structure functionalized at the other end.

[0037] In a preferred embodiment, the polymer having polyoxyethylene repeating units includes a compound shown in structural formula 2:

[0038]

[0039] Wherein, n=2-15; molecular weight is 200-1000;

[0040] R4 is selected from C4 to C20 substituents having 1 to 4 methyl groups.

[0041] R5 is selected from H, a C1-C6 substituent having a sulfonic acid group, a sulfate ester group, a sulfuric acid group, a carbonyl group or a phosphorus oxygen structure.

[0042] In some embodiments, the C4-C20 substituent having 1-4 methyl groups includes octyl, 2-ethyl-hexyl, octadecyl, oleyl, oleyl, isomeric decanyl and decanamide.

[0043] In some embodiments, R5 is selected from C1-C6 substituents having a sulfonic acid group, a sulfate group, a sulfate group, or a carbonyl structure.

[0044] On the basis of the polyoxyethylene ether structure, carboxyl, sulfonic acid, sulfate ester or carbonyl groups are introduced to further improve the anchoring of the polymerized monomers and polymers with polyoxyethylene repeating units on capacitors and various components, thereby improving the withstand voltage and lifespan.

[0045] In some embodiments, the polymer having polyoxyethylene repeating units includes one or more of isomeric decanol polyoxyethylene ether, fatty alcohol polyoxyethylene sodium sulfate, fatty alcohol polyoxyethylene ether ammonium sulfate, fatty alcohol polyoxyethylene sulfosuccinate disodium salt, dodecyl polyoxyethylene ether sulfate triethanolamine, fatty acid polyoxyethylene ether sodium carboxylate, fatty acid polyoxyethylene ether sodium sulfonate, and isomeric decanol polyoxyethylene ether phosphate.

[0046] In some embodiments, based on 100% of the total mass of the conductive polymer monomer composition, the mass proportion of the polymer having polyoxyethylene repeating units is 0.1% to 20%.

[0047] In specific embodiments, the mass percentage of the polymer having polyoxyethylene repeating units is 0.001%, 0.01%, 0.1%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%.

[0048] If the amount of the polymer having polyoxyethylene repeating units added is too small, the permeability performance of the polymerized monomer in the pores of the dielectric layer will not be significantly improved, and the data discreteness will be large; if the amount of the polymer having polyoxyethylene repeating units added is too large, it will affect the polymerization of the polymerized monomer and cause the conductivity after polymerization to decrease.

[0049] In some embodiments, based on the total mass of the conductive polymer monomer composition being 100%, the mass proportion of the polymerized monomer is 3% to 35%.

[0050] In specific embodiments, the mass percentage of the polymerized monomer is 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%, 21%, 22%, 23%, 24%, 25%, 27%, 30% or 35%.

[0051] In some embodiments, the solvent includes one or more of water, alcohol solvents, ether solvents, sulfone solvents, amide solvents, imide solvents, ketone solvents, lipid solvents, aromatic solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, and aromatic hydrocarbon solvents. Taking the total mass of the conductive polymer monomer composition as 100%, the mass proportion of the solvent is 45 to 96.9%.

[0052] In some embodiments, based on 100% of the total mass of the conductive polymer monomer composition, the total mass concentration of the polymerized monomer and the polymer having polyoxyethylene repeating units is 3.1% to 55%.

[0053] In a specific embodiment, based on the total mass of the conductive polymer monomer composition as 100%, the total mass concentration of the polymerized monomer and the polymer having polyoxyethylene repeating units is 3.1%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 27%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 37%, 39%, 40%, 42%, 44%, 46%, 50% or 55%.

[0054] If the total mass of the polymerized monomer and the polymer having polyoxyethylene repeating units is too low, it is difficult to ensure a complete film layer formed on the dielectric layer of the capacitor, affecting the film-forming performance; if the total mass of the polymerized monomer and the polymer having polyoxyethylene repeating units is too high, the overall viscosity of the conductive polymer monomer composition is too high, affecting the impregnation effect on the capacitor.

[0055] In some embodiments, the solvent is selected from one or more of water, methanol, ethanol, propanol, isopropanol, butanol, ethylene glycol, isobutanol, propylene glycol, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, dimethylacetamide, tetrahydrofuran, methyltetrahydrofuran, dichloromethane, 1,2-dichloroethane, ethyl acetate, propyl acetate, butyl acetate, ethyl propionate, propyl propionate, butyl propionate, methyl methacrylate, toluene, xylene, trimethylbenzene, acetonitrile, acetic acid, propionic acid, acetone, butanone, cyclohexanone, methyl butanone, propionic acid, pyridine, phenol, N-methylpyrrolidone, ethylene glycol monomethyl ether, triethylamine, and γ-butyrolactone.

[0056] Another embodiment of the present invention provides a conductive polymer, which is prepared by combining the conductive polymer monomer composition as described above with an oxidant.

[0057] In some embodiments, the molar ratio of the polymerizable monomer to the oxidant is (0.2-6):1, and the oxidant includes one or more of a peroxide structure, a persulfate structure, a perboric acid structure, and an aromatic quinone structure.

[0058] In a preferred embodiment, the oxidant is selected from tetramethylterephthalene.

[0059] The advantage is that tetramethyl parabenzoquinone acts as an oxidant and dopant to generate a conductive polymer during the polymerization process. After the polymerization is completed, it is removed from the capacitor by heating and sublimation, thereby improving the stability of the capacitor and avoiding the influence of residual oxidants on the performance of the capacitor.

[0060] In some embodiments, the oxidant is dissolved in a solvent to form an oxidant solution for use, and the solvent of the oxidant solution includes one or more of water, alcohol solvents, ether solvents, sulfone solvents, amide solvents, imide solvents, ketone solvents, lipid solvents, aromatic solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, and aromatic hydrocarbon solvents. Taking the total mass of the oxidant solution as 100%, the total mass concentration of the oxidant solute is 3% to 60%.

[0061] In a specific embodiment, based on the total mass of the oxidant solution as 100%, the total mass concentration of the oxidant solute is 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 27%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 37%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 47%, 49%, 50%, 51%, 52%, 55% or 60%.

[0062] If the total mass concentration of the oxidant is too low, it will affect the polymerization efficiency and film quality of the polymerizable monomers and reduce production efficiency; if the total mass concentration of the oxidant is too high, it will lead to too fast polymerization of the polymerizable monomers, making it inconvenient to carry out the impregnation operation.

[0063] Another embodiment of the present invention provides a method for preparing the conductive polymer as described above, comprising the following operations:

[0064] (1) A polymer having a polyoxyethylene repeating unit and a solvent are mixed, heated and stirred at 50 to 80° C. for 3 to 5 hours, and filtered to obtain a conductive polymer monomer composition.

[0065] (2) Preparation of oxidant solution: The oxidant is dissolved in a solvent to obtain an oxidant solution. The solute can be a single component or a combination of two components.

[0066] Another embodiment of the present invention provides an electrolytic capacitor, comprising an anode foil having a dielectric layer on its surface, a cathode foil, an electrolytic paper arranged between the anode foil and the cathode foil, and a conductive polymer as described above in contact with the dielectric layer or a conductive polymer prepared from the conductive high molecular monomer composition as described above.

[0067] In one embodiment, a capacitor element is composed of an anode foil having a dielectric layer on its surface, a cathode foil, and electrolytic paper disposed between the anode foil and the cathode foil.

[0068] In one embodiment, the impregnation method of the capacitor element or the anode foil includes the following steps:

[0069] A. Soak the capacitor element or anode foil in the conductive polymer monomer composition at a pressure of -95KPa to +100KPa for 1 to 40 minutes, take it out and dry it at a temperature of 80 to 190°C for 5 to 60 minutes.

[0070] B. Soak the capacitor element or anode foil dried in step A in an oxidant solution at a pressure of -95KPa to +100KPa for 1 to 40 minutes, take it out, and heat it in the range of 60 to 220°C for polymerization.

[0071] C. When the mass content of polymerized monomers in the conductive polymer monomer composition is less than 15%, steps A and B can be repeated 1 to 5 times to enhance and improve the performance.

[0072] D. Assemble and obtain electrolytic capacitors.

[0073] In another embodiment, the impregnation method of the capacitor element or the anode foil includes the following steps:

[0074] A. mixing a conductive polymer monomer composition and an oxidant solution to obtain a monomer + oxidant mixed solution, or directly preparing a monomer + oxidant combined solution including a conductive polymer monomer composition and an oxidant component to obtain a monomer + oxidant mixed solution;

[0075] B. Soak the capacitor element or anode foil in the monomer + oxidant mixed solution at a pressure of -95KPa to +100KPa for 1 to 40 minutes. Take it out and heat it at 60 to 190℃ to polymerize. After polymerization, keep it at 190-220℃ for 1 hour.

[0076] C. Assemble and obtain electrolytic capacitors.

[0077] The present invention is further described below by way of examples.

[0078] Table 1

[0079]

[0080]

[0081]

[0082] Example 1

[0083] This example is used to illustrate the preparation method of the conductive polymer monomer composition and electrolytic capacitor disclosed in the present invention, and includes the following steps:

[0084] Step 1, mixing and preparing a conductive polymer monomer composition according to the following weight ratio;

[0085] The polymerized monomer (compound 1) is 20%, the polymer having polyoxyethylene repeating units (compound 2) is 2%, and the balance is DMSO.

[0086] Step 2: prepare an oxidant solution according to the following weight ratio;

[0087] Oxidant (Compound 3) 30%, balance DMSO.

[0088] Step 3: The capacitor element is immersed in the conductive polymer monomer composition at a pressure of -85 KPa for 10 minutes, and then taken out and dried at a temperature of 150° C. for 30 minutes.

[0089] Step 4: Soak the element or anode body dried in step 3 in the oxidant solution at a pressure of -85 KPa for 10 min, take it out, and perform programmed temperature polymerization: keep warm at 40°C for 10 min, keep warm at 60°C for 10 min, keep warm at 80°C for 30 min, keep warm at 100°C for 30 min, keep warm at 120°C for 60 min, keep warm at 150°C for 30 min, and keep warm at 180°C for 5 min.

[0090] Step 5: After the polymerization is completed, the mixture is cooled to room temperature under the condition of humidity below 35%, and an electrolytic capacitor is assembled and subjected to aging treatment.

[0091] Example 2

[0092] Example 2 is used to illustrate the preparation method of the conductive polymer monomer composition and electrolytic capacitor disclosed in the present invention, and includes most of the operating steps in Example 1, except that:

[0093] The polymerizable monomers and their addition amounts, the polymer having polyoxyethylene repeating units and their addition amounts, the solvent and their addition amounts, and the oxidant and their addition amounts shown in Table 1 were used.

[0094] After completing steps 1, 2, 3, and 4 in Example 1, repeat steps 1, 2, 3, and 4 twice, and then proceed to step 5.

[0095] Embodiments 3 to 15

[0096] Examples 3 to 15 are used to illustrate the preparation method of the conductive polymer monomer composition and electrolytic capacitor disclosed in the present invention, and include most of the operating steps in Example 1, except that:

[0097] The polymerizable monomers and their addition amounts, the polymer having polyoxyethylene repeating units and their addition amounts, the solvent and their addition amounts, and the oxidant and their addition amounts shown in Table 1 were used.

[0098] Comparative Example 1

[0099] Comparative Example 1 is used to compare and illustrate the preparation method of the conductive polymer monomer composition and electrolytic capacitor disclosed in the present invention, and includes most of the operating steps in Example 1, except that:

[0100] The polymerizable monomers and their addition amounts, the polymer having polyoxyethylene repeating units and their addition amounts, the solvent and their addition amounts, and the oxidant and their addition amounts shown in Table 1 were used.

[0101] Performance Testing

[0102] The electrolytic capacitors prepared above were subjected to the following performance tests:

[0103] 1. Test environment: 25±1℃, air humidity: 60%;

[0104] 2. Capacity (uF): digital bridge, 120Hz;

[0105] DF(%): digital bridge, 120Hz;

[0106] ESR: Digital bridge, 100KHz;

[0107] Withstand voltage: Leakage current tester, increase the voltage, the voltage when the leakage current of a single capacitor reaches 5mA;

[0108] 125℃ life failure time: 125℃, rated voltage, load time when DF change rate is greater than 50% at 120Hz.

[0109] The test results obtained are entered in Table 2.

[0110] Table 2

[0111]

[0112]

[0113] It can be seen from the test results of Examples 1 to 5 and Comparative Example 1 that the conductive polymer monomer composition provided by the present invention can better solve the problem of poor wettability and film-forming properties of benzodifurandione and its derivatives in the capacitor dielectric layer, and ensure that the polymerized monomer forms a uniform conductive film on the surface of the capacitor dielectric layer, thereby improving the various properties of the electrolytic capacitor. Specifically, after the addition of compound 2, the capacity is increased from 49uF in Comparative Example 1 to 400-415uF. In disassembling the finished capacitors of Example 1 and Comparative Example 1, in Example 1 with the addition of compound 2, after polymerization, a uniform black conductive polymer can be formed on the electrolytic paper, such as Figure 1 As shown. In Comparative Example 1, due to the absence of compound 2, the conductive polymer monomer composition cannot fully enter the capacitor element, resulting in the inability to form a conductive polymer in the center of the electrolytic paper after polymerization. Figure 2 As shown, it only has a capacity of 49uF (design capacity 450uF). At the same time, it can be seen that after more conductive polymers are formed and loaded on the single electrolytic paper, the ESR will be significantly reduced.

[0114] By comparing the test results of Example 1, Examples 4 to 6 and Comparative Examples 1 and 2, the effect of the amount of compound 2 added on the performance can be obtained. After adding a certain amount of compound 2, the capacity extraction can be improved, but with too little compound 2 (Example 4), the capacity cannot be extracted to the optimum, and the ESR does not reach the lowest level. With too much compound 2 (Example 6), the capacity extraction is lower than that of Example 1 and Example 4. The data of the four examples prove that the addition of compound 2 can effectively improve the capacity extraction, and too little addition cannot fully improve the wettability and film-forming properties, the introduced capacity cannot be fully extracted, and the ESR cannot be optimized; if the addition amount is large enough, a large amount of non-conductive compound 2 dilutes the contact area between the conductive polymer and the dielectric layer, resulting in degradation of the capacity and ESR. Further affecting the withstand voltage and life characteristics.

[0115] Comparing the test results of Example 1 and Example 3, it can be seen that a higher proportion of conductive polymer monomers, although it will further reduce the ESR, will not significantly improve the life and withstand voltage, and will also increase the cost of monomer use.

[0116] Comparing the test results of Examples 7 to 13 with those of Example 1, it can be seen that the introduction of a second anion active structure based on Compound 2 enhances the anchoring ability between the conductive polymer and the dielectric layer, and between the conductive polymer and the electrolytic paper, and significantly improves the withstand voltage and 125°C load life. Thanks to the enhanced anchoring ability between the conductive polymer and the dielectric layer and the electrolytic paper, the capacity and ESR are further reduced.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A conductive polymer monomer composition, characterized in that: Includes the following components: A polymerizable monomer, a polymer having a polyoxyethylene repeating unit and a solvent, wherein the polymerizable monomer comprises a compound represented by structural formula 1; Wherein, R1 and R2 are each independently selected from -O-, -S- or Wherein R3 is selected from a hydrogen atom, a C1-C18 alkyl group, a C1-C18 alkylene group, a C1-C18 alkyl derivative or a C1-C18 alkylene derivative.

2. The conductive polymer monomer composition according to claim 1, characterized in that: The polymer having polyoxyethylene repeating units is selected from polyoxyethylene ethers terminated with an alkyl group or an alkyl substituent.

3. The conductive polymer monomer composition according to claim 2, characterized in that: The polymer having polyoxyethylene repeating units is selected from one or more polyoxyethylene ether derivatives having an alkyl or alkyl substituent end capping at one end and a sulfated, carboxylated, sulfonated or phosphated anion structure functionalized at the other end.

4. The conductive polymer monomer composition according to claim 1, characterized in that: The polymer having polyoxyethylene repeating units includes a compound shown in structural formula 2: Wherein, n=2-15; molecular weight is 200-1000; R4 is selected from C4 to C20 substituents having 1 to 4 methyl groups. R5 is selected from H, a C1-C6 substituent having a sulfonic acid group, a sulfate ester group, a sulfuric acid group, a carbonyl group or a phosphorus oxygen structure.

5. The conductive polymer monomer composition according to claim 1, characterized in that: The polymer having polyoxyethylene repeating units includes one or more of isomeric decanol polyoxyethylene ether, fatty alcohol polyoxyethylene sodium sulfate, fatty alcohol polyoxyethylene ether ammonium sulfate, fatty alcohol polyoxyethylene sulfosuccinate disodium salt, dodecyl polyoxyethylene ether sulfate triethanolamine, fatty acid polyoxyethylene ether sodium carboxylate, fatty acid polyoxyethylene ether sodium sulfonate, and isomeric decanol polyoxyethylene ether phosphate.

6. The conductive polymer monomer composition according to claim 1, characterized in that: Taking the total mass of the conductive polymer monomer composition as 100%, the mass of the polymer having polyoxyethylene repeating units accounts for 0.1% to 20%; taking the total mass of the conductive polymer monomer composition as 100%, the mass of the polymerized monomer accounts for 3% to 35%.

7. The conductive polymer monomer composition according to claim 1, characterized in that: The solvent includes one or more of water, alcohol solvents, ether solvents, sulfone solvents, amide solvents, imide solvents, ketone solvents, lipid solvents, aromatic solvents, aliphatic hydrocarbon solvents, alicyclic hydrocarbon solvents, and aromatic hydrocarbon solvents. Based on the total mass of the conductive polymer monomer composition as 100%, the mass proportion of the solvent is 45 to 96.9%.

8. A conductive polymer, characterized in that The method is prepared by combining the conductive polymer monomer composition as described in any one of claims 1 to 7 with an oxidant.

9. The conductive polymer according to claim 8, characterized in that The molar ratio of the polymerizable monomer to the oxidant is (0.2-6):1, and the oxidant includes one or more of peroxide compounds, persulfate compounds, perboric acid compounds, and aromatic quinone compounds.

10. An electrolytic capacitor, characterized in that: The invention comprises an anode foil with a dielectric layer on the surface, a cathode foil, an electrolytic paper arranged between the anode foil and the cathode foil, and a conductive polymer as claimed in any one of claims 8 to 9 or a conductive polymer prepared from the conductive high molecular monomer composition as claimed in any one of claims 1 to 7 in contact with the dielectric layer.

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