阅读说明：本技术 一种磺化双酚单体及其制备方法和应用 (Sulfonated bisphenol monomer and preparation method and application thereof ) 是由 郑吉富 张所波 代磊 于 2021-08-17 设计创作，主要内容包括：本发明提供了一种磺化双酚单体的制备方法,包括以下步骤：以酚酞和3-氨基丙烷磺酸为原料,在碱性化合物的催化作用下,进行反应得到磺化双酚单体。本发明采用成本低廉的酚酞和3-氨基丙烷磺酸作为原料,经一步反应制备得到高纯磺化双酚功能单体,其纯度可达99％,收率可达80％以上,目标产物磺化双酚功能单体可实现公斤级的批次稳定化制备。一方面避免了发烟硫酸、氯磺酸或浓硫酸等强酸媒介的使用。另一方面,只需要采用二氯甲烷洗涤和乙醇重结晶即可得到高纯度磺化双酚单体,克服了传统制备、纯化磺化单体时需要使用大量碱中和以及复杂的多次盐析过程。(The invention provides a preparation method of a sulfonated bisphenol monomer, which comprises the following steps: phenolphthalein and 3-aminopropane sulfonic acid are used as raw materials and react under the catalysis of an alkaline compound to obtain a sulfonated bisphenol monomer. The invention adopts phenolphthalein and 3-aminopropane sulfonic acid with low cost as raw materials, and prepares the high-purity sulfonated bisphenol functional monomer through one-step reaction, the purity of the high-purity sulfonated bisphenol functional monomer can reach 99 percent, the yield of the high-purity sulfonated bisphenol functional monomer can reach more than 80 percent, and the target product sulfonated bisphenol functional monomer can realize kilogram-level batch stable preparation. On one hand, the use of strong acid media such as fuming sulfuric acid, chlorosulfonic acid or concentrated sulfuric acid is avoided. On the other hand, the high-purity sulfonated bisphenol monomer can be obtained only by washing with dichloromethane and recrystallizing with ethanol, and the problems of large amount of alkali for neutralization and complicated multiple salting-out process in the traditional preparation and purification of sulfonated monomers are overcome.)

1. A sulfonated bisphenol monomer having the structure of formula i or a salt thereof:

2. a preparation method of sulfonated bisphenol monomer comprises the following steps:

phenolphthalein and 3-aminopropane sulfonic acid are used as raw materials and react under the catalysis of an alkaline compound to obtain a sulfonated bisphenol monomer.

3. The method according to claim 1, wherein the basic compound is selected from one or more of NaOH, KOH, sodium carbonate, and potassium carbonate.

4. The process according to claim 1, wherein the solvent of the reaction is selected from high-boiling polar aprotic solvents.

5. The method according to claim 4, wherein the solvent for the reaction is selected from the group consisting of NMP, DMSO, and NMP/H₂O or DMSO/H₂O。

6. The method according to claim 1, wherein the pressure of the reaction is 0.0 to 1.0 Mpa; the reaction temperature is 150-200 ℃.

7. The method according to claim 1, wherein the post-treatment of the reaction is:

cooling the system to room temperature, adding dichloromethane, and filtering; then washed with dichloromethane to give a solid powder.

8. The sulfonated bisphenol monomer according to claim 1 or the sulfonated bisphenol monomer prepared by the preparation method according to any one of claims 2 to 7 is used for preparing a sulfonated aromatic proton exchange membrane.

9. A sulfonated aromatic proton exchange membrane is prepared by polymerization reaction of the sulfonated bisphenol monomer of claim 1 or the sulfonated bisphenol monomer prepared by the preparation method of any one of claims 2 to 7.

Technical Field

The invention relates to the technical field, in particular to a sulfonated bisphenol monomer and a preparation method and application thereof.

Background

Proton exchange membranes are key materials for fuel cells, electrodialysis and other technologies. There are two main types of common sulfonated proton exchange membranes. One type is a perfluorosulfonic acid series membrane, for example: nafion and Aquivion, and the like; because of good thermal stability, electrochemical oxidation resistance, mechanical property and higher proton conductivity, the composite material is widely applied to the fields of proton exchange membrane fuel cells and the like. However, perfluorosulfonic acid membranes have problems of high fuel permeability, high production cost, and serious fluorine contamination during production. Another type is a non-fluorine (or partially fluorine-containing) sulfonated proton exchange membrane. Particularly, the sulfonated aromatic proton exchange membrane has received much attention because of its excellent thermal stability and mechanical strength, easy structure modulation, lower fuel permeability and other advantages.

At present, the preparation of sulfonated aromatic proton exchange membranes is mainly based on the copolymerization method of post-sulfonation or sulfonation functional monomers of polymers, for example: sulfonated polyether sulfone, sulfonated polyether ketone, sulfonated polyphenyl, sulfonated polyimide, and the like. Whether polymers or monomers are used as raw materials, strong acid media such as fuming sulfuric acid, chlorosulfonic acid, concentrated sulfuric acid (or mixed acid of methanesulfonic acid and concentrated sulfuric acid) and the like are generally used, and then the corresponding proton exchange membrane material is obtained through ion exchange reaction. These methods have the following disadvantages: 1) post-sulfonation of polymer: the method is mainly controlled by the reaction time, the reaction temperature and the concentration of the used sulfonation reagent. The sulfonation degree is not easy to be accurately controlled, and the position and the number of the sulfonic acid groups have randomness. The use of strong acid media requires equipment with acid corrosion resistance. In addition, the post-sulfonation method also easily causes polymer crosslinking and main chain degradation, thereby causing problems of unstable performance and the like. 2) Sulfonation functional monomer method: in order to solve the disadvantages caused by the post-sulfonation method, the synthesis of the sulfonated functional monomer and the preparation of the sulfonated aromatic proton exchange membrane by copolymerization are widely studied. However, most of the sulfonated functional monomers reported in the prior art are concentrated on sulfonated dihalogen monomers (such as sulfonated dichlorodiphenyl sulfone, sulfonated difluorobenzophenone, sulfonated 2, 5-dichlorobenzophenone), sulfonated diamine monomers, sulfonated binaphthyl dianhydride, and the like, which restricts the development of high-performance proton exchange membranes. Because the sulfonated functional monomer generally has remarkable hygroscopicity and good water solubility, a large amount of alkali is needed to neutralize excessive acid during preparation and purification, and the purity meeting the polymerization requirement can be obtained through a plurality of salting-out processes, the purification operation steps are complicated, the preparation cost of the sulfonated polymer is increased, the complicated operation steps and the high purification cost limit the wide application of the sulfonated functional monomer. Therefore, the development of a novel low-cost sulfonated functional monomer and a high-efficiency green preparation method thereof has important significance for enriching the variety of proton exchange membrane materials and expanding the application field of the proton exchange membrane materials.

Disclosure of Invention

In view of the above, the technical problem to be solved by the present invention is to provide a sulfonated bisphenol monomer, a preparation method and an application thereof, wherein the sulfonated bisphenol monomer can be prepared without using a strong acid medium, and the post-treatment is simple.

In order to achieve the above objects, the present invention provides a sulfonated bisphenol monomer having a structure represented by formula I:

preferably, the salt may be a potassium salt or a sodium salt.

Specifically, the potassium salt and the sodium salt respectively have structures shown in the following formulas I-a or I-b:

the invention provides a preparation method of the sulfonated bisphenol monomer, which comprises the following steps:

phenolphthalein and 3-aminopropane sulfonic acid are used as raw materials and react under the catalysis of an alkaline compound to obtain a sulfonated bisphenol monomer.

The equation for the above reaction is as follows:

preferably, the alkaline compound is selected from NaOH, KOH, sodium carbonate, potassium carbonate, etc.; more preferably sodium or potassium carbonate.

Preferably, in the present invention, the solvent of the reaction is selected from high boiling polar aprotic solvents. Further preferably, the solvent of the reaction is selected from NMP, DMSO, NMP/H₂O、DMSO/H₂And O. More preferably NMP/H₂O or DMSO/H₂O。

Preferably, the present invention employs the above NMP/H₂O or DMSO/H₂When the solvent is mixed with O, a water separator is used in the reaction system, the water separation treatment is firstly carried out on the system, and then the reaction is continuously carried out, which is beneficial to improving the reaction conversion rate.

Preferably, the pressure of the reaction is 0.0-1.0 Mpa; more preferably 0.5 to 1.0 MPa; more preferably 1.0 MPa.

Preferably, the reaction temperature is 150-200 ℃; more preferably 150-180 ℃; further preferably 180 ℃.

In some embodiments of the invention, the preparation method comprises the following steps:

adding a solvent into a stainless steel pressure-resistant kettle provided with a water separator, suspending phenolphthalein and 3-aminopropane sulfonic acid in the solvent, and adding a catalyst under the condition of stirring. Then, vacuum degassing (preferably three times), heating and reacting under the protection of nitrogen, and closing a valve of the water separator after the water yield is stable. The reaction is continued (preferably for 6 hours) while the temperature is raised (preferably 180 ℃ C.) and the pressure is adjusted to 1.0 MPa.

The post-reaction treatment is preferably: cooling the system to room temperature, adding dichloromethane, and filtering; then washed with dichloromethane to give a solid powder.

In the present invention, the solid powder is preferably recrystallized. The solvent for recrystallization is preferably ethanol.

The product obtained by the preparation method and the purification process is characterized in structure by using a nuclear magnetic resonance hydrogen spectrum and a mass spectrum respectively, and is proved to be a target product of the sulfonated bisphenol functional monomer.

The invention provides the application of the sulfonated bisphenol monomer or the sulfonated bisphenol monomer prepared by the preparation method in preparing a sulfonated aromatic proton exchange membrane.

The invention provides a sulfonated aromatic proton exchange membrane, which is prepared by polymerization reaction of the sulfonated bisphenol monomer or the sulfonated bisphenol monomer prepared by the preparation method.

The method for preparing the sulfonated aromatic proton exchange membrane is not particularly limited, and may be a method known to those skilled in the art.

In the present invention, it is preferable that the sulfonated bisphenol monomer is polymerized with 4,4' -difluorobenzophenone, an alkaline compound and a polar aprotic solvent in a solvent.

The basic compound is preferably K₂CO₃。

The polar aprotic solvent may be DMSO or NMP, among other polar aprotic solvents well known to those skilled in the art.

The temperature of the polymerization reaction is 180-210 ℃, and the time of the polymerization reaction is 8-10 h.

The sulfonated aromatic proton exchange membrane provided by the invention has higher conductivity.

Compared with the prior art, the invention provides a preparation method of a sulfonated bisphenol monomer, which comprises the following steps: phenolphthalein and 3-aminopropane sulfonic acid are used as raw materials and react under the catalysis of an alkaline compound to obtain a sulfonated bisphenol monomer. The invention adopts phenolphthalein and 3-aminopropane sulfonic acid with low cost as raw materials, and prepares the high-purity sulfonated bisphenol functional monomer through one-step reaction, the purity of the high-purity sulfonated bisphenol functional monomer can reach 99 percent, the yield of the high-purity sulfonated bisphenol functional monomer can reach more than 80 percent, and the target product sulfonated bisphenol functional monomer can realize kilogram-level batch stable preparation. On one hand, the use of strong acid media such as fuming sulfuric acid, chlorosulfonic acid or concentrated sulfuric acid is avoided. On the other hand, the high-purity sulfonated bisphenol monomer can be obtained only by washing with dichloromethane and recrystallizing with ethanol, and the problems of large amount of alkali for neutralization and complicated multiple salting-out process in the traditional preparation and purification of sulfonated monomers are overcome.

Drawings

FIG. 1 is a nuclear magnetic resonance hydrogen spectrum of a sulfonated bisphenol monomer prepared in example 7 of the present invention;

FIG. 2 is a mass spectrum of sulfonated bisphenol monomer prepared in example 7 of the present invention;

FIG. 3 is a NMR chart of the sulfonated polymer prepared in example 8 of the present invention.

Detailed Description

In order to further illustrate the present invention, the following examples are provided to describe the preparation of sulfonated bisphenol monomers of the present invention in detail.

Example 1

400mL of NMP solvent was added to a stainless steel pressure resistant kettle, phenolphthalein (0.2mol,63.6g) and 3-aminopropanesulfonic acid (0.204mol,28.4g) were suspended in the solvent, and potassium hydroxide (0.102mol,5.71g) was added with stirring. Subsequently, the mixture was degassed three times in vacuum, heated to 180 ℃ under nitrogen protection while adjusting the pressure to 0.5MPa, reacted for 10 hours, then cooled to room temperature, added with dichloromethane, stirred, then filtered, and washed with dichloromethane several times to obtain a solid powder. The conversion rate is 11.5% by NMR hydrogen spectrum test.

Example 2

400mL of NMP solvent was added to a stainless steel pressure resistant kettle, phenolphthalein (0.2mol,63.6g) and 3-aminopropanesulfonic acid (0.204mol,28.4g) were suspended in the solvent, and weak base potassium carbonate (0.102mol,14.1g) was added with stirring. Subsequently, vacuum degassing was carried out three times, heating was carried out to 180 ℃ under nitrogen protection while adjusting the pressure to 0.5MPa, reaction was carried out for 10 hours, then, cooling was carried out to room temperature, methylene chloride was added, stirring was carried out, and then, filtration was carried out. Washing with dichloromethane several times to obtain solid powder. The conversion rate is 45.6% by hydrogen nuclear magnetic resonance spectroscopy.

Example 3

400mL of a mixed solvent of NMP/water (4: 1) was added to a stainless steel pressure resistant vessel equipped with a water separator, phenolphthalein (0.2mol,63.6g) and 3-aminopropanesulfonic acid (0.204mol,28.4g) were suspended in the solvent, and weak base potassium carbonate (0.51mol,70.4g) was added with stirring. And then, vacuum degassing is carried out for three times, the mixture is heated to 160 ℃ under the protection of nitrogen, and after 4 hours of reaction, a water separator valve is closed after the water yield is stable. The temperature is increased to 180 ℃, the pressure is adjusted to 0.5MPa at the same time, and the reaction is continued for 6 hours. After cooling to room temperature, dichloromethane was added and filtered. Washing with dichloromethane several times to obtain solid powder. The conversion rate is 75.9% by hydrogen nuclear magnetic resonance spectroscopy.

Example 4

400mL of a mixed solvent of DMSO/water (4: 1) was added to a stainless steel pressure resistant vessel equipped with a water trap, phenolphthalein (0.2mol,63.6g) and 3-aminopropanesulfonic acid (0.204mol,28.4g) were suspended in the solvent, and weak base potassium carbonate (0.51mol,70.4g) was added with stirring. And then, vacuum degassing is carried out for three times, the mixture is heated to 160 ℃ under the protection of nitrogen, and after 4 hours of reaction, a water separator valve is closed after the water yield is stable. The temperature is increased to 180 ℃, the pressure is adjusted to 0.5MPa at the same time, and the reaction is continued for 6 hours. After cooling to room temperature, dichloromethane was added and filtered. Washing with dichloromethane several times to obtain solid powder. The conversion rate is 54.2% by NMR hydrogen spectrum test.

Example 5

400mL of a mixed solvent of NMP/water (4: 1) was added to a stainless steel pressure resistant vessel equipped with a water separator, phenolphthalein (0.2mol,63.6g) and 3-aminopropanesulfonic acid (0.204mol,28.4g) were suspended in the solvent, and weak base potassium carbonate (0.51mol,70.4g) was added with stirring. And then, vacuum degassing is carried out for three times, the mixture is heated to 160 ℃ under the protection of nitrogen, and after 4 hours of reaction, a water separator valve is closed after the water yield is stable. The temperature is increased to 180 ℃, the pressure is adjusted to 1.0MPa at the same time, and the reaction is continued for 6 hours. After cooling to room temperature, dichloromethane was added and filtered. Washing with dichloromethane several times to obtain solid powder. The conversion rate is 88.0 percent by a hydrogen nuclear magnetic resonance spectrum test.

Example 6

400mL of a mixed solvent of NMP/water (4: 1) was added to a stainless steel pressure resistant vessel equipped with a water separator, phenolphthalein (0.2mol,63.6g) and 3-aminopropanesulfonic acid (0.204mol,28.4g) were suspended in the solvent, and weakly basic sodium carbonate (0.51mol,54.1g) was added with stirring. And then, vacuum degassing is carried out for three times, the mixture is heated to 160 ℃ under the protection of nitrogen, and after 4 hours of reaction, a water separator valve is closed after the water yield is stable. The temperature is increased to 180 ℃, the pressure is adjusted to 1.0MPa at the same time, and the reaction is continued for 6 hours. After cooling to room temperature, dichloromethane was added and filtered. Washing with dichloromethane several times to obtain solid powder. The conversion rate was 74.8% by NMR spectroscopy.

Example 7

To a stainless steel pressure resistant vessel equipped with a water separator was added 4.0L of a mixed solvent of NMP/water (4: 1), phenolphthalein (2mol,636g) and 3-aminopropanesulfonic acid (2.04mol,284g) were suspended in the solvent, and weak base potassium carbonate (1.02mol,141g) was added under stirring. And then, vacuum degassing is carried out for three times, the mixture is heated to 160 ℃ under the protection of nitrogen, and after 4 hours of reaction, a water separator valve is closed after the water yield is stable. The temperature is increased to 180 ℃, the pressure is adjusted to 1.0MPa at the same time, and the reaction is continued for 6 hours. After cooling to room temperature, dichloromethane was added and filtered. Washing with dichloromethane several times to obtain solid powder. The conversion rate was 87.0% by NMR spectroscopy.

And finally, recrystallizing the solid powder obtained by filtering with ethanol to obtain a target product, wherein the separation yield is over 80 percent.

The NMR spectrum of the product (solvent: DMSO-d6) is shown in FIG. 1.

The mass spectrum of the product is shown in FIG. 2.

Comparative example 1

To a stainless steel pressure resistant kettle was added 400mL of water, phenolphthalein (0.2mol,63.6g) and 3-aminopropanesulfonic acid (0.204mol,28.4g) were suspended in the solvent, and weak base potassium carbonate (0.102mol,14.1g) was added with stirring. And then, vacuum degassing is carried out for three times, the mixture is heated to 100 ℃ under the protection of nitrogen, the pressure is adjusted to 0.5MPa at the same time, the mixture is cooled to room temperature after 10 hours of reaction, and solid powder is obtained after filtration and multiple times of water washing. The solid powder is verified to be the raw material phenolphthalein by nuclear magnetic resonance hydrogen spectrum.

From the above examples and comparative examples, it can be seen that water has a significant effect on the above reaction, and the presence of small amounts of water strongly affects the conversion of the reaction. For example, the pure water system in comparative example 1 hardly reacted. After the reaction system is subjected to water separation treatment, the conversion rate of the reaction is obviously increased. The degree of basicity also significantly affects the conversion of the above reaction, for example, when KOH is used, the conversion is significantly lower than K₂CO₃. In addition, the pressure of the reaction system also has a certain influence on the conversion rate.

Example 8

2L of a polar aprotic solvent NMP was charged in a 5L reactor, and 1mol of the sulfonated bisphenol monomer prepared in example 7, 1mol of 4,4' -difluorobenzophenone, and anhydrous K were added under stirring₂CO₃(3.2mol) and 2L of toluene are added into the reaction kettle in sequence. Under the protection of nitrogen and at the temperature of 140 ℃, carrying out water diversion reaction for 6 hours, and after water diversion is finishedThe temperature is increased to 210 ℃ and the reaction is continued for 8 h. After the polymer viscosity reached the target, the reaction was terminated and the reaction system was cooled to room temperature. And then, adding water to the polymer solution for solidification and crushing to obtain white powdery polymer resin. And washing the resin with water, desalting and vacuum drying to obtain the target sulfonated polymer. The NMR spectrum of the sulfonated polymer is shown in FIG. 3; in addition, the prepared polymer is dissolved in DMSO and subjected to film formation by a solvent evaporation method, and the proton conductivity of the prepared polymer film material at 30-80 ℃ can reach 60-120 mS cm^-1。

The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.