Sulfonated polyetheretherketone and preparation method thereof

Abstract

The invention discloses sulfonated polyether ether ketone and a preparation method thereof, and relates to the technical field of high polymer materials, the method comprises the following steps: taking 4, 4 '-difluorobenzophenone, bisphenol A and potassium 2, 5-dihydroxybenzenesulfonate as raw materials, taking potassium carbonate as a catalyst, taking dimethyl sulfoxide and xylene as solvents, stirring and introducing nitrogen, and reacting at 140 DEG C for 90 minutes; raising the temperature to 155 DEG C, continuously reacting, and separating condensed water and xylene out of a reaction system in the reaction process; adding an end-capping reagent to terminate the reaction to obtain a yellow jelly; introducing the yellow jelly into ethanol, soaking, crushing, washing and drying to obtain sulfonated polyether-ether-ketone; in the first step, the particle size of the potassium carbonate is 30-300 meshes. By adopting potassium carbonate with smaller particle size, the temperature of the condensation reaction can be reduced from 180 DEG C to 155 DEG C, and the reaction time is shortened, so that the decomposition of dimethyl sulfoxide can be avoided, no malodorous gas is generated in the preparation process, the potential safety hazard is eliminated, and the purity of the product is improved.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a sulfonated polyetheretherketone and a preparation method thereof. Background Art

[0002] Sulfonated polyetheretherketone not only inherits the mechanical strength, high temperature resistance, corrosion resistance and other characteristics of polyetheretherketone, but also has good alcohol resistance, proton conductivity and water lubrication properties, which make it have broad application prospects in many industrial fields. In recent years, some synthesis methods of sulfonated polyetheretherketone with different sulfonation degrees and different structures have been reported one after another. Generally, dimethyl sulfoxide or cyclopentane sulfone is used as solvent, toluene or xylene is used as water-carrying agent, and condensation is carried out under the action of potassium carbonate. For example, the Chinese invention patent with application number 202311696691.9 discloses a method for synthesizing sulfonated PEEK resin, which uses bisphenol A, 4,4'-difluorobenzophenone, and potassium 2,5-dihydroxybenzenesulfonate as raw materials, dimethyl sulfoxide (DMSO) as solvent, and reacts at 180°C under the action of catalyst and dehydrating agent. However, in this preparation method, DMSO is easily decomposed under high temperature conditions, especially in the presence of acids, bases, halides, etc., to produce impurities such as dimethyl sulfide and water, which affect the reaction process and product purity. In addition, dimethyl sulfide is a low-boiling, malodorous gas, which is a very serious safety hazard in industrial production and has great harm to the environment and personnel.

[0003] As an improvement, the Chinese invention patent with application number 202411018649.6 discloses the synthesis of sulfonated polyetheretherketone resin using bisphenol A, 4,4'-difluorobenzophenone, and 4,4'-difluorobenzophenone-3,3'-disulfonic acid disodium salt as raw materials. During the synthesis process, the temperature is reduced to 165°C, but the 4,4'-difluorobenzophenone-3,3'-disulfonic acid disodium salt used in this method is a customized product, which is not only difficult to purchase, but also has a high cost, resulting in poor market competitiveness of the prepared sulfonated polyetheretherketone. Therefore, how to reduce the reaction temperature of bisphenol A, 4,4'-difluorobenzophenone, and potassium 2,5-dihydroxybenzenesulfonate and increase its reaction rate is an urgent problem to be solved in the preparation of sulfonated polyetheretherketone.

[0004] It can be seen that the existing technology still needs to be improved and enhanced. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a sulfonated polyetheretherketone and a preparation method thereof, aiming to solve the defects of the existing preparation process of sulfonated polyetheretherketone due to the easy decomposition of dimethyl sulfoxide under high temperature conditions, easy to produce impurities and cause safety hazards.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for preparing sulfonated polyetheretherketone, wherein the method comprises:

[0008] Step 1: using 4,4'-difluorobenzophenone, bisphenol A and potassium 2,5-dihydroxybenzenesulfonate as raw materials, potassium carbonate as catalyst, dimethyl sulfoxide and xylene as solvents, stirring and passing nitrogen, reacting at 140°C for 90 minutes;

[0009] Step 2: Raise the temperature to 155° C., continue the reaction, and separate the condensation water and xylene from the reaction system during the reaction;

[0010] Step 3: Add a capping agent to terminate the reaction and obtain a yellow colloid;

[0011] Step 4: introducing the yellow colloid into ethanol, soaking, crushing, washing and drying to obtain sulfonated polyetheretherketone;

[0012] In the step 1, the average particle size of the potassium carbonate is 30-300 mesh.

[0013] In the method for preparing sulfonated polyetheretherketone, in step 1, the molar ratio of 4,4'-difluorobenzophenone, bisphenol A, potassium 2,5-dihydroxybenzenesulfonate and potassium carbonate is (98-102):(97-101):(1-2):(220-260).

[0014] In the method for preparing sulfonated polyetheretherketone, in step three, the end-capping agent is a dimethyl sulfoxide solution of 4,4'-difluorobenzophenone, wherein the amount of the 4,4'-difluorobenzophenone is 2% of the amount of 4,4'-difluorobenzophenone added in step one, and the amount of the dimethyl sulfoxide is 5% of the amount of the dimethyl sulfoxide added in step one.

[0015] In the method for preparing sulfonated polyetheretherketone, in the step 1, the average particle size of the potassium carbonate is 30-50 meshes, and in the step 2, the reaction time at 155° C. is 150 to 200 minutes.

[0016] In the method for preparing sulfonated polyetheretherketone, in the step 1, the average particle size of the potassium carbonate is 50-80 mesh, and in the step 2, the reaction time at 155° C. is 120 to 160 minutes.

[0017] In the method for preparing sulfonated polyetheretherketone, in the step 1, the average particle size of the potassium carbonate is 80-120 meshes, and in the step 2, the reaction time at 155° C. is 100-120 minutes.

[0018] In the method for preparing sulfonated polyetheretherketone, in the step 1, the average particle size of the potassium carbonate is 120-150 mesh, and in the step 2, the reaction time at 155° C. is 70 to 100 minutes.

[0019] In the method for preparing sulfonated polyetheretherketone, in the step 1, the average particle size of the potassium carbonate is 150-200 mesh, and in the step 2, the reaction time at 155° C. is 50 to 70 minutes.

[0020] In the method for preparing sulfonated polyetheretherketone, in the step 1, the average particle size of the potassium carbonate is 200-300 mesh, and in the step 2, the reaction time at 155° C. is 30-40 minutes.

[0021] A sulfonated polyetheretherketone, wherein it is prepared by the method as described above and has a number average molecular weight of 10000-20000.

[0022] Beneficial effects:

[0023] The invention provides a sulfonated polyetheretherketone and a preparation method thereof. The preparation method uses 4,4'-difluorobenzophenone, bisphenol A and potassium 2,5-dihydroxybenzenesulfonate as raw materials. By using potassium carbonate with a smaller particle size, the temperature of the condensation reaction can be reduced from 180°C to 155°C and the reaction time can be shortened, thereby avoiding the decomposition of dimethyl sulfoxide and preventing the generation of malodorous gas during the preparation process. The method can not only improve the purity of the product and make the production safer, but also improve the reaction efficiency and shorten the reaction time. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 The present invention provides a flow chart of the method for preparing sulfonated polyetheretherketone. DETAILED DESCRIPTION

[0025] The present invention provides a sulfonated polyetheretherketone and a preparation method thereof. In order to make the purpose, technical scheme and effect of the present invention clearer and more specific, the present invention is further described in detail with reference to the following examples. It should be understood that the specific examples described herein are only used to explain the present invention and are not used to limit the present invention.

[0026] A preferred embodiment of the present invention provides a method for preparing sulfonated polyetheretherketone, the method comprising:

[0027] Step 1: using 4,4'-difluorobenzophenone, bisphenol A and potassium 2,5-dihydroxybenzenesulfonate as raw materials, potassium carbonate as catalyst, dimethyl sulfoxide and xylene as solvents, stirring and passing nitrogen, reacting at 140°C for 90 minutes;

[0028] Step 2: Raise the temperature to 155° C., continue the reaction, and separate the condensation water and xylene from the reaction system during the reaction;

[0029] Step 3: Add a capping agent to terminate the reaction and obtain a yellow colloid;

[0030] Step 4: introducing the yellow colloid into ethanol, soaking, crushing, washing and drying to obtain sulfonated polyetheretherketone;

[0031] In the step 1, the average particle size of the potassium carbonate is 30-300 mesh.

[0032] In the preparation method, 4,4'-difluorobenzophenone, bisphenol A and potassium 2,5-dihydroxybenzenesulfonate are used as raw materials. By using potassium carbonate with a smaller particle size, the temperature of the condensation reaction can be reduced from 180°C to 155°C, and the reaction time can be shortened. Therefore, the decomposition of dimethyl sulfoxide can be avoided, and no odorous gas is generated during the preparation process. Not only can the purity of the product be improved, making the production safer, but also the efficiency of the reaction can be improved and the reaction time can be shortened.

[0033] Since the amount of 4,4'-difluorobenzophenone, bisphenol A, and potassium 2,5-dihydroxybenzenesulfonate will affect the sulfonation degree of the product, and experiments have shown that sulfonated polyetheretherketone with a sulfonation degree of 1 to 3% has good water lubricity, in this regard, in a more preferred embodiment, in the step 1, when the molar ratio of 4,4'-difluorobenzophenone, bisphenol A, potassium 2,5-dihydroxybenzenesulfonate, and potassium carbonate is (98 to 102):(97 to 101):(1 to 2):(220 to 260), a sulfonated polyetheretherketone with a sulfonation degree of 1 to 3% can be obtained.

[0034] Since the end-capping agent and its addition amount will affect the end-capping effect, in order to make the molecular weight distribution narrower, in the step three, the end-capping agent is a dimethyl sulfoxide solution of 4,4'-difluorobenzophenone, and the amount of the 4,4'-difluorobenzophenone is 2% of the amount of 4,4'-difluorobenzophenone added in the step one, and the amount of the dimethyl sulfoxide is 5% of the amount of the dimethyl sulfoxide added in the step one.

[0035] Since the molecular weight of sulfonated polyetheretherketone affects its mechanical properties, generally speaking, sulfonated polyetheretherketone with a high molecular weight usually has better strength and toughness. This is because a high molecular weight means a longer molecular chain, and more entanglements can be formed between the molecular chains, so that stress can be better transmitted and dispersed when subjected to external forces, making the material more difficult to be damaged. In terms of processing performance, the molecular weight will affect the melt viscosity of sulfonated polyetheretherketone. Generally speaking, the higher the molecular weight, the greater the melt viscosity. However, in the injection molding process, sulfonated polyetheretherketone with too high a molecular weight is difficult to flow due to its high melt viscosity, which is not conducive to filling the mold cavity; however, if the molecular weight of sulfonated polyetheretherketone is too low, although the fluidity is good, the mechanical properties of the product will deteriorate, so it is necessary to select a polymer with a suitable molecular weight according to the processing method. For solubility, sulfonated polyetheretherketone with a lower molecular weight is generally easier to dissolve, because small molecular chains are easier to diffuse in solvents and surrounded by solvent molecules, while high molecular weight sulfonated polyetheretherketone has a long molecular chain and strong interchain forces, and is relatively difficult to dissolve. In addition, in terms of glass transition temperature, an increase in molecular weight will increase the glass transition temperature (Tg) of sulfonated polyetheretherketone.

[0036] It was found through experiments that the mechanical properties, processing properties, solubility properties and glass transition temperature of sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 are comprehensively good. Therefore, in the present invention, by controlling the average particle size of potassium carbonate and the time of the condensation reaction, a sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 can be obtained.

[0037] In one embodiment, in the step one, the average particle size of the potassium carbonate is 30-50 mesh, and in the step two, the reaction time at 155° C. is 150-200 min. After reaction under such reaction conditions, a sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 can be obtained.

[0038] In another embodiment, the average particle size of potassium carbonate in step one is 50-80 mesh, and in step two, the reaction time at 155° C. is 120-160 min to obtain sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000.

[0039] In another embodiment, in the step 1, the average particle size of the potassium carbonate is 80-120 meshes, and in the step 2, the reaction time at 155° C. is 100-120 min, and a sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 can be obtained.

[0040] In another embodiment, in the step 1, the average particle size of the potassium carbonate is 120-150 mesh, and in the step 2, the reaction time at 155° C. is 70-100 min, and a sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 can be obtained.

[0041] In another embodiment, in the step 1, the average particle size of the potassium carbonate is 150-200 mesh, and in the step 2, the reaction time at 155° C. is 50-70 min, and a sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 can be obtained.

[0042] In another embodiment, in the step 1, the average particle size of the potassium carbonate is 200-300 mesh, and in the step 2, the reaction time at 155° C. is 30-40 min, and a sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 can be obtained.

[0043] However, when the average particle size of potassium carbonate is greater than 300 mesh, the particle size is too small and the reaction rate is too fast, making it difficult to control the degree of polymerization of the reaction, resulting in uncontrollable molecular weight. Therefore, the preferred particle size range of potassium carbonate is between 30-300 mesh, which can make the reaction rate controllable. By only controlling the reaction time, sulfonated polyetheretherketone with a number average molecular weight of 10,000-20,000 can be obtained.

[0044] Of course, when it is necessary to obtain a sulfonated polyetheretherketone with a larger number average molecular weight, the reaction time can be adaptively adjusted according to the particle size of potassium carbonate to obtain a sulfonated polyetheretherketone within the target molecular weight range. For example, when other conditions remain unchanged, when the average particle size of potassium carbonate is 40 mesh, the reaction is carried out at 155°C for 240 minutes, and a sulfonated polyetheretherketone with a molecular weight of 27886 can be obtained. For another example, when the particle size of potassium carbonate is 250 mesh, the reaction is carried out at 155°C for 100 minutes, and a sulfonated polyetheretherketone with a molecular weight of 41868 can be obtained. In the actual production process, the particle size and reaction time of potassium carbonate can be adjusted according to actual needs.

[0045] The second aspect of the present invention provides a sulfonated polyetheretherketone, which is prepared by the aforementioned method. The molecular weight of the sulfonated polyetheretherketone can be adjusted according to the reaction conditions. As a preferred example, the number average molecular weight of the sulfonated polyetheretherketone is 10000-20000, which has good comprehensive performance.

[0046] To further illustrate the preparation method of sulfonated polyetheretherketone provided by the present invention, the following examples are provided.

[0047] Example 1

[0048] A method for preparing sulfonated polyetheretherketone, such as Figure 1 As shown, including:

[0049] Step 1, in a dry single-layer reactor, dimethyl sulfoxide, 4,4'-difluorobenzophenone, bisphenol A, potassium 2,5-dihydroxybenzenesulfonate, potassium carbonate (average particle size 30 mesh) and xylene are added in sequence, wherein the molar ratio of 4,4'-difluorobenzophenone, bisphenol A, potassium 2,5-dihydroxybenzenesulfonate and potassium carbonate is 100:100:2:240, nitrogen is passed, the reaction system is heated from room temperature to 140°C, and stirred at this temperature for 90 minutes;

[0050] Step 2: heating to 155°C and reacting at this temperature for 200 minutes. During the reaction, condensation water and xylene are separated from the reaction system;

[0051] Step 3: adding a blocking agent to terminate the reaction to obtain a yellow colloid; the blocking agent is a dimethyl sulfoxide solution of 4,4'-difluorobenzophenone, wherein the amount of the 4,4'-difluorobenzophenone is 2% of the amount of the 4,4'-difluorobenzophenone added in step 1, and the amount of the dimethyl sulfoxide is 5% of the amount of the dimethyl sulfoxide added in step 1;

[0052] Step 4: The yellow colloid is introduced into ethanol while hot and quickly solidified into a strip of plastic. After soaking in ethanol for 10 hours, the strip of plastic is broken and washed with a 60% ethanol aqueous solution at 80°C (60 min×10 times) to remove the residual solvent, reaction monomer and potassium carbonate in the crude product. The obtained white powder is dried in a forced air drying oven at 120°C for 48 hours to obtain sulfonated polyetheretherketone.

[0053] Example 2

[0054] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are substantially the same as those in Example 1, except that: (1) in step 1, the particle size of potassium carbonate is 80 mesh; and (2) in step 2, the reaction time is 160 min.

[0055] Example 3

[0056] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are substantially the same as those in Example 1, except that: (1) in step 1, the particle size of potassium carbonate is 150 mesh; and (2) in step 2, the reaction time is 75 min.

[0057] Example 4

[0058] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are substantially the same as those in Example 1, except that: (1) in step 1, the particle size of potassium carbonate is 200 mesh; and (2) in step 2, the reaction time is 50 min.

[0059] Example 5

[0060] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are substantially the same as those in Example 1, except that: (1) in step 1, the particle size of potassium carbonate is 300 mesh; and (2) in step 2, the reaction time is 30 min.

[0061] Example 6

[0062] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are substantially the same as those in Example 1, except that in step 1, the molar ratio of 4,4'-difluorobenzophenone, bisphenol A, potassium 2,5-dihydroxybenzenesulfonate and potassium carbonate is 102:101:1:220.

[0063] Example 7

[0064] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are substantially the same as those in Example 1, except that in step 1, the molar ratio of 4,4'-difluorobenzophenone, bisphenol A, potassium 2,5-dihydroxybenzenesulfonate and potassium carbonate is 98:97:2:260.

[0065] Comparative Example 1

[0066] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are substantially the same as those in Example 1, except that in step 1, the particle size of potassium carbonate is 10 mesh.

[0067] Comparative Example 2

[0068] A method for preparing sulfonated polyetheretherketone, wherein the preparation steps are basically the same as those in Example 1, except that: (1) in step 1, the particle size of potassium carbonate is 10 mesh; and (2) in step 2, the reaction temperature is 180° C. and the reaction time is 200 min.

[0069] The number average molecular weight and melt index of the sulfonated polyetheretherketone prepared in Examples 1-7 and Comparative Examples 1 and 2 are as follows:

[0070]

[0071]

[0072] As can be seen from Table 1, Examples 1-7 can all obtain sulfonated polyetheretherketone with a number average molecular weight between 10000 and 20000. It can be seen that by using potassium carbonate with an average particle size of 30-300 mesh, the reaction temperature can be reduced to 155°C, and the decomposition of dimethyl sulfoxide can be avoided; and, as can be seen from Examples 1-5, at the same reaction temperature, the smaller the particle size of potassium carbonate, the shorter the reaction time required, indicating that fine-particle potassium carbonate can greatly increase the reaction rate and reduce energy consumption.

[0073] In Comparative Example 1, due to the large average particle size of potassium carbonate, high molecular weight sulfonated polyetheretherketone cannot be obtained at 155°C. As shown in Comparative Example 2, the molecular weight can only be increased by increasing the reaction temperature, but high temperature will cause dimethyl sulfoxide to decompose, resulting in a foul odor during the reaction.

[0074] It is understandable that those skilled in the art can make equivalent substitutions or changes based on the technical solution and inventive concept of the present invention, and all these changes or substitutions should fall within the protection scope of the claims attached to the present invention.

Claims

1. A method for preparing sulfonated polyetheretherketone, characterized in that: The method comprises: Step 1: using 4,4'-difluorobenzophenone, bisphenol A and potassium 2,5-dihydroxybenzenesulfonate as raw materials, potassium carbonate as catalyst, dimethyl sulfoxide and xylene as solvents, stirring and passing nitrogen, reacting at 140°C for 90 minutes; Step 2: Raise the temperature to 155° C., continue the reaction, and separate the condensation water and xylene from the reaction system during the reaction; Step 3: Add a capping agent to terminate the reaction and obtain a yellow colloid; Step 4: introducing the yellow colloid into ethanol, soaking, crushing, washing and drying to obtain sulfonated polyetheretherketone; In the step 1, the average particle size of the potassium carbonate is 30-300 mesh.

2. The method for preparing sulfonated polyetheretherketone according to claim 1, characterized in that: In the step 1, the molar ratio of the 4,4'-difluorobenzophenone, bisphenol A, potassium 2,5-dihydroxybenzenesulfonate and potassium carbonate is (98-102):(97-101):(1-2):(220-260).

3. The method for preparing sulfonated polyetheretherketone according to claim 2, characterized in that: In the step three, the end-capping agent is a dimethyl sulfoxide solution of 4,4'-difluorobenzophenone, wherein the amount of the 4,4'-difluorobenzophenone is 2% of the amount of the 4,4'-difluorobenzophenone added in the step one, and the amount of the dimethyl sulfoxide is 5% of the amount of the dimethyl sulfoxide added in the step one.

4. The method for preparing sulfonated polyetheretherketone according to claim 3, characterized in that: In the step 1, the average particle size of the potassium carbonate is 30-50 mesh, and in the step 2, the reaction time at 155° C. is 150-200 min.

5. The method for preparing sulfonated polyetheretherketone according to claim 3, characterized in that: In the step 1, the average particle size of the potassium carbonate is 50-80 mesh, and in the step 2, the reaction time at 155° C. is 120-160 min.

6. The method for preparing sulfonated polyetheretherketone according to claim 3, characterized in that: In the step 1, the average particle size of the potassium carbonate is 80-120 mesh, and in the step 2, the reaction time at 155° C. is 100-120 min.

7. The method for preparing sulfonated polyetheretherketone according to claim 3, characterized in that: In the step 1, the average particle size of the potassium carbonate is 120-150 mesh, and in the step 2, the reaction time at 155° C. is 70-100 min.

8. The method for preparing sulfonated polyetheretherketone according to claim 3, characterized in that: In the step 1, the average particle size of the potassium carbonate is 150-200 mesh, and in the step 2, the reaction time at 155° C. is 50-70 minutes.

9. The method for preparing sulfonated polyetheretherketone according to claim 3, characterized in that: In the step 1, the average particle size of the potassium carbonate is 200-300 mesh, and in the step 2, the reaction time at 155° C. is 30-40 minutes.

10. A sulfonated polyetheretherketone, characterized in that: It is prepared by the method described in any one of claims 5 to 9, and has a number average molecular weight of 10,000 to 20,000.

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