CN112608494A - Preparation method of perfluorosulfonic acid resin dispersion liquid - Google Patents
Preparation method of perfluorosulfonic acid resin dispersion liquid Download PDFInfo
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- CN112608494A CN112608494A CN202011399193.4A CN202011399193A CN112608494A CN 112608494 A CN112608494 A CN 112608494A CN 202011399193 A CN202011399193 A CN 202011399193A CN 112608494 A CN112608494 A CN 112608494A
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- acid resin
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/02—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques
- C08J3/03—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media
- C08J3/07—Making solutions, dispersions, lattices or gels by other methods than by solution, emulsion or suspension polymerisation techniques in aqueous media from polymer solutions
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2329/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
- C08J2329/10—Homopolymers or copolymers of unsaturated ethers
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Abstract
Disclosed is a method for producing a perfluorosulfonic acid resin dispersion, which comprises: putting the perfluorosulfonic acid resin solid into a mixed solvent of water and an organic solvent, and heating to dissolve the perfluorosulfonic acid resin solid to obtain a perfluorosulfonic acid resin dispersion liquid; after liquid-liquid separation, obtaining perfluorosulfonic acid resin separation liquid; and centrifuging and filtering the separation liquid to obtain the perfluorosulfonic acid resin dispersion liquid.
Description
Technical Field
The invention relates to a preparation method of perfluorosulfonic acid resin dispersion liquid, and the perfluorosulfonic acid resin dispersion liquid prepared by the method has improved stability.
Background
The hydrogen fuel cell automobile is one of the main technical paths for the development of new energy automobiles in China. The most critical component of the heart-fuel cell electric pile used for the hydrogen fuel cell automobile is a membrane electrode. The perfluorosulfonic acid proton exchange membrane and the catalyst are important core materials in the membrane electrode. The perfluorinated sulfonic acid resin dispersion liquid is a key premise for preparing proton exchange membranes and catalyst slurry with excellent performance, and various preparation methods of the perfluorinated sulfonic acid resin dispersion liquid are also provided in the field.
U.S. Pat. No. 4,4433082 discloses a process for preparing perfluorosulfonic acid resin dispersion, which comprises dissolving perfluorosulfonic acid resin dispersion in water and lower alcohol as solvent at 220 deg.C or higher and 3MPa or higher in a corrosion-resistant high-nickel alloy container for 3-18 hours under stirring.
US20080214684a1 discloses a process for preparing perfluorosulfonic acid resin dispersions by solution dispersion in aqueous tetrahydrofuran solvent at lower pressures (about 2MPa) and lower temperatures (about 150-.
Chinese patent CN101273487B and US patent application US20130210943a1 disclose that in a glass lined pressure vessel, perfluorosulfonic acid resin and solvent are dissolved at elevated temperature of 140-.
Chinese patent CN103146001B mentions that perfluorosulfonic acid resin solid is placed in a mixed solvent of water and an organic solvent, stirred for 20min to 5h, transferred into an autoclave, and dissolved for 1 to 120 h under high temperature and high pressure under the protection of inert gas to obtain a mixed solution of perfluorosulfonic acid resin, water and ether generated by dehydroxylation of the organic solvent; and (3) after the mixed solution is subjected to liquid-liquid separation, taking the lower layer solution to obtain the high-stability perfluorosulfonic acid resin dispersion liquid with small particle size, uniform chain dispersion and narrow particle size distribution.
Although the existing perfluorosulfonic acid resin dispersion liquid has certain storage stability, the perfluorosulfonic acid resin dispersion liquid still has gelatinous precipitation after being stored for a period of time, and the final use of the perfluorosulfonic acid resin dispersion liquid is influenced. Accordingly, there remains a need in the art to develop a method for preparing perfluorosulfonic acid resin dispersions, which have improved storage stability.
Disclosure of Invention
An object of the present invention is to provide a process for producing a perfluorosulfonic acid resin dispersion liquid having improved storage stability.
Accordingly, the present invention relates to a process for preparing a perfluorosulfonic acid resin dispersion, which comprises:
putting the perfluorosulfonic acid resin solid into a mixed solvent of water and an organic solvent, and heating to dissolve the perfluorosulfonic acid resin solid to obtain a perfluorosulfonic acid resin dispersion liquid;
after liquid-liquid separation, obtaining perfluorosulfonic acid resin separation liquid;
and centrifuging and filtering the separation liquid to obtain the perfluorosulfonic acid resin dispersion liquid.
Detailed Description
The conventional perfluorosulfonic acid resin dispersion has a gelatinous precipitate after storage for a certain period of time, for example, 0.5 to 1 year, and even if the final product is filtered to remove possible impurities or insoluble substances when preparing the perfluorosulfonic acid resin dispersion, it is difficult to improve the storage stability of the perfluorosulfonic acid resin dispersion. The inventors of the present invention have found that the cause of such gelatinous precipitation is not caused by the collision and aggregation of perfluorosulfonic acid resin molecules in the dispersion, but is caused by the presence of fine particles invisible to the naked eye in the perfluorosulfonic acid resin dispersion, which gradually become large during storage and eventually precipitate. Based on such findings, the inventors proposed that the dispersion of perfluorosulfonic acid obtained be subjected to centrifugation and filtration treatment, thereby eliminating fine particles that may become gel centers. The present invention has been completed based on this finding.
1. Putting the perfluorosulfonic acid resin solid into a mixed solvent of water and an organic solvent, heating and dissolving to obtain perfluorosulfonic acid resin dispersion liquid
The perfluorosulfonic acid resin suitable for the process of the present invention is not particularly limited and may be a conventional perfluorosulfonic acid resin known in the art. In one embodiment of the invention, the perfluorosulfonic acid resin comprises a perfluorocarbon backbone-CF2-CF2-or-CF2-CF-and- [ OCF2CF(CF3)]x-O[CF2]y-SO3H side chain, wherein x ═ 0 or 1, y ═ 2-4; preferably-CF2-CF2-a block copolymer with a segment of the formula:
in one embodiment of the present invention, theThe perfluorosulfonic acid resin includes-CF2-CF2-main chain and- [ OCF2C(CF3)F]m-O[CF2CF2]n-SO3H side chain, m ═ 0 or 1, n ═ 1 or 2.
The Equivalent Weight (EW) of the perfluorosulfonic acid resin of the present invention is not particularly limited and may be a conventional Equivalent Weight known in the art. In one embodiment of the present invention, the equivalent weight of the perfluorosulfonic acid resin is 600-1000g/mol, preferably 650-950g/mol, and more preferably 700-900 g/mol.
The organic solvent suitable for the method of the present invention is not particularly limited, and may be a conventional organic solvent known in the art. In one embodiment of the invention, the organic solvent is selected from C1-5Alkanols (e.g. methanol, ethanol, N-propanol, isopropanol, N-butanol, ethylene glycol, propylene glycol, butylene glycol, glycerol), aniline, acetone, methyl amides (e.g. dimethylformamide, dimethylacetamide), tetrahydrofuran, diethylamine, acetaldehyde, dimethyl sulfoxide, cyclohexane, N-methylpyrrolidone or mixtures of two or more thereof.
The volume content of water in the mixed solvent is not particularly limited and may be a conventional content known in the art. In one embodiment of the present invention, the volume percentage of water in the mixed solvent of water and organic solvent is 30% to 90%, preferably 35% to 85%, more preferably 40% to 80%, preferably 45% to 75%, and preferably 50% to 70%.
The perfluorosulfonic acid resin in the method of the present invention is 1 to 50%, preferably 5 to 40%, more preferably 8 to 35%, preferably 10 to 30%, preferably 12 to 25% by weight based on the total weight of the perfluorosulfonic acid resin and the mixed solvent.
In one embodiment of the invention, the temperature-increasing dissolution is carried out in an inert atmosphere. The suitable inert atmosphere is not particularly limited, and may be a conventional inert atmosphere known in the art. For example, the inert atmosphere may be an inert atmosphere formed by one of nitrogen, argon, or a mixture thereof. From the viewpoint of cost, a nitrogen atmosphere is preferred.
The temperature of the invention is 100-320 deg.C, preferably 120-300 deg.C, more preferably 150-250 deg.C, more preferably 180-220 deg.C.
The dissolution at elevated temperature of the present invention can be carried out in a closed vessel at a pressure of 3MPa to 30MPa, preferably 3.2 to 20MPa, more preferably 3.5 to 15MPa, preferably 3.8 to 10MPa, preferably 4 to 5 MPa.
In one embodiment of the present invention, the time for warming and dissolving is 1 to 120 hours, preferably 2 to 100 hours, more preferably 3 to 80 hours, preferably 4 to 60 hours, and preferably 5 to 40 hours.
In one embodiment of the present invention, the method of the present invention comprises placing the solid perfluorosulfonic acid resin in a mixed solvent of water and an organic solvent, stirring, transferring into an autoclave, and dissolving under an inert gas at high temperature and high pressure.
The perfluorosulfonic acid resin dispersion obtained by heating and dissolving by the method comprises water and a mixed solvent of ether generated by dehydroxylation of an organic solvent.
2. Liquid-liquid separation to obtain perfluorosulfonic acid resin separation liquid
The liquid-liquid separation in the process of the present invention is mainly aimed at removing ethers from the perfluorosulfonic acid resin dispersion. As described above, such ethers are formed by dehydroxylation in organic solvents. The liquid-liquid separation method to be used is not particularly limited and may be a conventional method known in the art. For example, suitable liquid-liquid separation methods include distillation, extractive separation.
The separation liquid after the ether is removed by liquid-liquid separation has no resin residue which is white and not completely dissolved, and is a high-stability perfluorosulfonic acid resin solution with uniformly dispersed molecular chains, small particle size and narrow particle size distribution.
The process for forming the perfluorosulfonic acid resin separation liquid of the present invention may be a conventional process known in the art. In one embodiment of the present invention, the perfluorosulfonic acid resin separation liquid of the present invention is prepared by the method disclosed in CN103146001A (which is incorporated herein by reference as part of the present invention).
3. Centrifuging and filtering the separation liquid to obtain perfluorosulfonic acid resin dispersion liquid
The method for centrifuging and filtering the separated liquid is not particularly limited, and may be a conventional centrifugation and filtration method known in the art. In one embodiment of the present invention, the centrifugation rotation speed is 5000-.
In one embodiment of the invention, the centrifugation time is from 0.5 to 10 minutes, preferably from 0.8 to 8 minutes, more preferably from 1 to 6 minutes, preferably from 1.5 to 5 minutes.
The invention eliminates the tiny particles which can affect the storage stability in the separation liquid by carrying out centrifugal filtration on the separation liquid of the perfluorosulfonic acid resin dispersion liquid. As a result, the separation liquid obtained by the process of the present invention does not precipitate after storage for, for example, 6 months, and has improved storage stability.
Examples
The invention is further illustrated by the following examples.
Example 1
Preparing 200ml of mixed solution of water and isopropanol, wherein the volume fraction of the water is 30%, and adding 3g of mixed solution with a main chain structure of-CF2-CF2-, the side chain structure is-O [ CF2CF2]2-SO3Stirring H perfluorosulfonic acid resin solid particles (equivalent weight EW is 1000g/mol) for 20min, transferring into a high-pressure kettle, sealing, introducing nitrogen for protection and stirring, heating to 100 ℃, keeping the temperature for 1H at 3MPa, cooling to room temperature, taking out the mixed solution, carrying out normal-temperature and normal-pressure extraction and separation on the mixed solution of the perfluorosulfonic acid resin, water and ether generated by dehydroxylation of an organic solvent through carbon tetrachloride, and taking the lower-layer solution to obtain the perfluorosulfonic acid resin separation solution. The separated liquid was visually observed to have no insoluble matter.
And (3) placing the separation liquid in a centrifugal separator, and centrifuging for 2 minutes at the rotating speed of 20000 revolutions per minute to obtain the perfluorosulfonic acid resin dispersion liquid.
No precipitate was found to be precipitated after the perfluorosulfonic acid resin dispersion was allowed to stand at room temperature for 6 months.
Example 2
Preparing water and water200ml of mixed solution of alcohol and dimethylformamide, wherein the volume fraction of water is 20%, the volume fraction of methanol is 40%, the volume fraction of methylamide is 40%, and 197g of a mixed solution having a main chain structure of-CF is added2-CF2-, side chain structure is- [ OCF ]2C(CF3)F]-O[CF2CF2]-SO3Stirring solid particles of H perfluorosulfonic acid resin (equivalent weight EW is 1200g/mol) for 5H, transferring into a high-pressure kettle, sealing, introducing argon gas for protection, stirring, heating to 320 ℃, keeping the temperature for 130H under the pressure of 30MPa,
and then cooling to room temperature, taking out the obtained mixed solution, distilling and separating the mixed solution of the perfluorosulfonic acid resin, water and ether generated by dehydroxylation of an organic solvent, and taking out the lower-layer solution to obtain the perfluorosulfonic acid resin separation solution.
The separated liquid was centrifuged in a centrifuge at 18000 rpm for 2.2 minutes to obtain a perfluorosulfonic acid resin dispersion.
No precipitate was found to be precipitated after the perfluorosulfonic acid resin dispersion was allowed to stand at room temperature for 6 months.
Example 3
Preparing a 200ml mixed solution of water methanol and methacrylamide, wherein the volume fraction of water is 40%, the volume fraction of methanol is 30% and the volume fraction of methacrylamide is 30%, and adding 100g of a main chain structure of-CF2-CF2-, the side chain structure is-O [ CF2CF2]2-SO3Stirring H perfluorosulfonic acid resin solid particles for 3 hours, transferring into a high-pressure kettle, sealing, introducing a mixed gas (volume ratio is 1: 1) of nitrogen and argon, stirring under protection, heating to 260 ℃, keeping the temperature for 50 hours under the pressure of 20MPa, cooling to room temperature, taking out the mixed solution, extracting and separating the mixed solution of the perfluorosulfonic acid resin, water and ether generated by dehydroxylation of an organic solvent through carbon tetrachloride at normal temperature and normal pressure, and taking a lower-layer solution, namely the perfluorosulfonic acid resin separating solution.
The separated liquid was centrifuged in a centrifuge at 18000 rpm for 2.2 minutes to obtain a perfluorosulfonic acid resin dispersion.
No precipitate was found to be precipitated after the perfluorosulfonic acid resin dispersion was allowed to stand at room temperature for 6 months.
Comparative example 1
A perfluorosulfonic acid resin separation solution was prepared as described in example 1.
And carrying out suction filtration treatment on the separation liquid to obtain the perfluorosulfonic acid resin dispersion liquid.
When the perfluorosulfonic acid resin dispersion was left at room temperature, a very small amount of gelatinous insoluble matter was observed to be formed in about 1 month.
Claims (10)
1. A process for preparing a perfluorosulfonic acid resin dispersion comprising:
putting the perfluorosulfonic acid resin solid into a mixed solvent of water and an organic solvent, and heating to dissolve the perfluorosulfonic acid resin solid to obtain a perfluorosulfonic acid resin dispersion liquid;
after liquid-liquid separation, obtaining perfluorosulfonic acid resin separation liquid;
and centrifuging and filtering the separation liquid to obtain the perfluorosulfonic acid resin dispersion liquid.
2. The method of claim 1, wherein the organic solvent is selected from the group consisting of C1-5Alkanols, anilines, acetone, methyl amides, tetrahydrofuran, diethylamine, acetaldehyde, dimethyl sulfoxide, cyclohexane, N-methylpyrrolidone or mixtures of two or more thereof.
3. The method of claim 2, wherein C is1-5The alkanol is selected from methanol, ethanol, n-propanol, isopropanol, n-butanol, ethylene glycol, propylene glycol, butylene glycol, and glycerol; the methyl amide is selected from dimethylformamide and dimethylacetamide.
4. The method according to any one of claims 1 to 3, wherein the volume percentage of water in the mixed solvent of water and organic solvent is 30% to 90%, preferably 35% to 85%, more preferably 40% to 80%, preferably 45% to 75%, preferably 50% to 70%.
5. The process according to any one of claims 1 to 3, wherein when the solid perfluorosulfonic acid resin is placed in a mixed solvent of water and an organic solvent, the perfluorosulfonic acid resin is present in an amount of 1 to 50%, preferably 5 to 40%, more preferably 8 to 35%, preferably 10 to 30%, and preferably 12 to 25%, based on the total weight of the perfluorosulfonic acid resin and the mixed solvent.
6. The process according to any one of claims 1 to 3, wherein the temperature for dissolution is raised to a temperature of 100 ℃ to 320 ℃, preferably 120 ℃ to 300 ℃, more preferably 150 ℃ to 250 ℃, preferably 180 ℃ to 220 ℃.
7. A process according to any one of claims 1 to 3, wherein the pressure at which dissolution is carried out at elevated temperature is from 3MPa to 30MPa, preferably from 3.2 MPa to 20MPa, more preferably from 3.5 MPa to 15MPa, preferably from 3.8 MPa to 10MPa, preferably from 4 MPa to 5 MPa.
8. A process according to any one of claims 1 to 3, wherein the dissolution at elevated temperature is carried out for a period of time in the range 1 to 120 hours, preferably 2 to 100 hours, more preferably 3 to 80 hours, preferably 4 to 60 hours, preferably 5 to 40 hours.
9. The process according to any one of claims 1 to 3, wherein the centrifugation speed is 5000-.
10. The method according to any one of claims 1 to 3, wherein the centrifugation is carried out for a period of time of from 0.5 to 10 minutes, preferably from 0.8 to 8 minutes, more preferably from 1 to 6 minutes, preferably from 1.5 to 5 minutes.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113754821A (en) * | 2021-11-09 | 2021-12-07 | 国家电投集团氢能科技发展有限公司 | Purification method of perfluorinated sulfonic acid resin dispersion liquid and ion exchange membrane |
| CN114276561A (en) * | 2021-11-26 | 2022-04-05 | 国家电投集团氢能科技发展有限公司 | Preparation method of perfluorosulfonic acid resin dispersion liquid |
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| CN103146001A (en) * | 2013-03-08 | 2013-06-12 | 武汉理工大学 | Preparation method of perfluorosulfonic acid resin solution with uniformly dispersed molecular chains |
| CN104140542A (en) * | 2013-05-09 | 2014-11-12 | 宝应县润华静电涂装工程有限公司 | Perfluorinated sulfonic acid resin solution preparation method |
| KR101948192B1 (en) * | 2018-05-30 | 2019-02-13 | 주식회사 시노펙스 | Method and apparatus for pfsa ionomer dispersion |
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2020
- 2020-12-02 CN CN202011399193.4A patent/CN112608494A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1884352A (en) * | 2005-06-24 | 2006-12-27 | 大连新源动力股份有限公司 | Process for preparing perfluorinated sulfonic resin solution by using waste ion exchange membrane in chlor-alkali industry |
| CN103146001A (en) * | 2013-03-08 | 2013-06-12 | 武汉理工大学 | Preparation method of perfluorosulfonic acid resin solution with uniformly dispersed molecular chains |
| CN104140542A (en) * | 2013-05-09 | 2014-11-12 | 宝应县润华静电涂装工程有限公司 | Perfluorinated sulfonic acid resin solution preparation method |
| KR101948192B1 (en) * | 2018-05-30 | 2019-02-13 | 주식회사 시노펙스 | Method and apparatus for pfsa ionomer dispersion |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113754821A (en) * | 2021-11-09 | 2021-12-07 | 国家电投集团氢能科技发展有限公司 | Purification method of perfluorinated sulfonic acid resin dispersion liquid and ion exchange membrane |
| CN114276561A (en) * | 2021-11-26 | 2022-04-05 | 国家电投集团氢能科技发展有限公司 | Preparation method of perfluorosulfonic acid resin dispersion liquid |
| CN114276561B (en) * | 2021-11-26 | 2024-06-04 | 国家电投集团氢能科技发展有限公司 | Preparation method of perfluorosulfonic acid resin dispersion liquid |
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