Polyetherketoneketone and a method for producing the same

Abstract

The application discloses a kind of polyether ketone ketone and preparation method thereof, the application is first added terephthaloyl chloride or isophthaloyl chloride and diphenyl ether, then under the condition of adding catalyst anhydrous aluminium chloride, low-temperature prepolymerization for a certain time, then the remaining diphenyl ether is added to complete the short-chain end-capping reaction.The application reduces the temperature in the early stage of the starting reaction process and adopts the reflux method in the selection of the washing reagent in the later stage, so that the purity and molecular weight of the obtained high molecular polymer polyether ketone ketone are high.The content of aluminum, a catalyst contained in PEKK, is lower, and the intrinsic viscosity (molecular weight) and tensile strength of the tested product are higher.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a polyether ketone ketone and its preparation method. Background Technology

[0002] Polyetherketoneketone (PEKK) is a class of aromatic ring polymers whose main chain contains one repeating ether bond and two repeating ketone bonds, with a density of 1.28-1.31 g / cm³. 3 The melting point is 300℃-375℃. Polyetherketoneketone (PEKK) is a high-performance specialty engineering plastic, belonging to the polyaryletherketone family. It is a semi-crystalline polymer material, and its glass transition temperature (155℃~175℃) and melting temperature (305℃~375℃) can be controlled and adjusted according to the amount of monomer used. Its molecular structure, with its orderly arrangement of benzene rings, ether bonds, and ketone groups, endows PEKK molecules with highly stable chemical bonding characteristics, giving it excellent properties such as high strength, high chemical resistance, and high continuous service temperature. It can be used in aerospace and many other wide-ranging industrial applications, including the preparation of thermoplastic composites. It can also be used to prepare biomedical implant materials.

[0003] For in vivo use, polyaryletherketone (PAEK) materials must further meet biocompatibility requirements. Ideally, the synthesized polymer should be free of unreacted monomers, catalyst residues, or other reactive components; that is, high polymer purity is required to meet biocompatibility requirements. In reality, impurities within the polymer can lead to melt instability during processing. This can be a serious problem during further processing and molding, as instability can cause performance changes during manufacturing, potentially affecting the performance of the finished product in use. This is highly undesirable for applications with high structural and performance requirements, such as aerospace.

[0004] Currently, there are two main methods for synthesizing PEKK: nucleophilic substitution and electrophilic substitution. While nucleophilic substitution can produce polyether ketones with good stability, its synthesis conditions are demanding, increasing production costs. Electrophilic substitution, on the other hand, has simpler synthesis conditions, typically employing low-temperature polymerization, requiring simpler processes and making it easier to industrialize. However, the polyether ketones synthesized using electrophilic substitution have lower molecular weights and insufficient purity.

[0005] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] The purpose of this invention is to provide a polyether ketone ketone and its preparation method, which can overcome the technical problems of low molecular weight and insufficient purity of polyether ketone ketone synthesized by electrophilic substitution in the prior art.

[0007] To achieve the above objectives, embodiments of the present invention provide a method for preparing polyetherketone, comprising:

[0008] Under nitrogen protection, terephthaloyl chloride and / or isophthaloyl chloride, diphenyl ether and polymer solvent are mixed and the low temperature is controlled at -20 to -5°C.

[0009] During the stirring process, anhydrous aluminum chloride is added, and the temperature is raised to 10℃ to 40℃ and stirred for 0.1h to 1h to obtain the first mixed solution;

[0010] Diphenyl ether is added to the first mixed solution, and the temperature is controlled at 25℃-40℃. The reaction is carried out for 0.1h-6h to obtain the second mixed solution.

[0011] Add the capping agent and maintain the reaction temperature at 25℃-40℃ for 1 to 4 hours to obtain a mixture of polyether ketone ketone products;

[0012] The polyether ketone ketone product mixture was added to an ice-cold acidic protic solution for quenching, and then filtered to obtain crude polyether ketone ketone solid.

[0013] The crude polyether ketone ketone solid was washed with alcohol and ketone detergents, and then washed with water to obtain wet polyether ketone ketone solid.

[0014] The wet polyether ketone solid was dried to obtain polyether ketone.

[0015] In one or more embodiments of the present invention, the mass ratio of terephthaloyl chloride and / or isophthaloyl chloride and diphenyl ether in the first mixed solution is 2.39:1-1.5:1.

[0016] In one or more embodiments of the present invention, the ratio of terephthaloyl chloride and / or isophthaloyl chloride and diphenyl ether in the second mixed solution is 1.3:1 to 1:1.1.

[0017] In one or more embodiments of the present invention, the capping agent is diphenyl ether, benzoyl chloride or p-chlorobenzoyl chloride, with the mass of terephthaloyl chloride and / or isophthaloyl chloride and diphenyl ether in the second mixed solution being m, and the mass of the capping agent being less than or equal to 0.87m.

[0018] In one or more embodiments of the present invention, the polymer solvent is one or a mixture of two or more of o-dichlorobenzene, dichloroethane, and dichloromethane.

[0019] In one or more embodiments of the present invention, the mass ratio of the anhydrous aluminum chloride added to the diphenyl ether in the first mixed solution is 6:1 to 3:1.

[0020] In one or more embodiments of the present invention, the alcohol and ketone detergents are selected from methanol, ethanol, propanol or acetone.

[0021] In one or more embodiments of the present invention, the prepared polyether ketone contains aluminum metal residue in the range of 0-50 ppm and chloride ion content in the range of 0-100 ppm.

[0022] In one or more embodiments of the present invention, the temperature for drying wet polyether ketone solid is between 120°C and 180°C.

[0023] An embodiment of the present invention also provides a polyetherketone ketone, which is prepared by the method described above.

[0024] Compared with existing technologies, the synthesis conditions adopted in this invention can effectively solve the problem of synthesizing high-purity and high-molecular-weight polyether ketone (PEKK) polymers using electrophilic substitution. The resulting PEKK polymer has better thermal stability and can be processed into products through extrusion molding, injection molding, compression molding, etc. Due to its high purity, the processed materials can be used not only in military, machinery, and shipbuilding industries, but also meet the requirements of PEKK for implants in medical devices. Attached Figure Description

[0025] Figure 1 This is a scanning electron microscope (SEM) image of a powder sample according to an embodiment of the present invention;

[0026] Figure 2 This is a thermogravimetric analysis (TG) chart of a powder sample according to an embodiment of the present invention. Detailed Implementation

[0027] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0028] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0029] A method for preparing polyetherketone according to a preferred embodiment of the present invention includes:

[0030] s1. Under nitrogen protection, add a mixture of terephthaloyl chloride and / or isophthaloyl chloride, diphenyl ether and polymerization solvent into the reactor, and keep the temperature of the mixture in the range of -20 to -5℃; while stirring, slowly add anhydrous aluminum chloride to obtain a first mixture; and stir at 10℃ to 40℃ for 0.1h-1h.

[0031] s2. Add a predetermined amount of diphenyl ether to the first mixture, stir for 0.1h-3h to obtain a second mixture, and heat the second mixture to 25℃-40℃ to react for 0.1h-6h.

[0032] s3. Add a predetermined amount of capping agent within a temperature range of 25°C to 40°C, and maintain the reaction at this temperature for 1 to 4 hours to obtain a mixture of polyether ketone ketone products.

[0033] s4. The polyether ketone ketone product mixture obtained above is added to an acidic proton solution of ice for quenching, and then filtered to obtain crude polyether ketone ketone solid.

[0034] s5. The crude polyether ketone solid is repeatedly refluxed and washed with methanol or other alcohol or ketone solutions and acidic solutions, and then washed with water to obtain wet polyether ketone solid.

[0035] s6. The wet polyether ketone solid is dried under reduced pressure in a temperature range of 120°C to 180°C to obtain polyether ketone PEKK.

[0036] In step s5, the detergent is repeatedly refluxed for washing. This method not only saves detergent, but also allows the detergent to be recycled during the industrial production of PEKK, and ensures that the impurities in PEKK are minimized.

[0037] The prepared polyether ketone contains 0-50 ppm of residual aluminum and 0-100 ppm of chloride ions. Residual volatiles are less than 0.1%.

[0038] In this embodiment of the invention, terephthaloyl chloride or isophthaloyl chloride and diphenyl ether are added first, followed by the addition of anhydrous aluminum chloride catalyst. The mixture is then prepolymerized at low temperature for a certain period, and the remaining diphenyl ether is added to complete the short-chain end-capping reaction. This embodiment of the invention achieves high purity and high molecular weight of the obtained polyetherketone (PEKK) polymer by lowering the temperature during the initial reaction and by adopting appropriate washing reagent selection and reflux methods in the later stages. This is manifested in the lower aluminum catalyst content in PEKK, and its higher intrinsic viscosity (higher molecular weight) and greater tensile strength.

[0039] Example 1

[0040] The entire reaction process was carried out using N2 as a protective gas. In a 1L reactor, the stirring device was turned on, and then 8.51g of diphenyl ether, 20.3g of terephthaloyl chloride and 400ml of dichloromethane were slowly added.

[0041] The temperature inside the entire reactor was lowered to -15°C. After the temperature stabilized, 37.32g of aluminum chloride was slowly added to the reactor. 30 minutes after the catalyst was added, the temperature of the reactor was raised to 30°C.

[0042] After reacting for 1 hour, 8.51 g of diphenyl ether was added to the reactor, and the temperature was maintained at 30°C for 3 hours.

[0043] Then, 0.01 g of benzoyl chloride was added to the reactor and the reaction was continued at 30°C for 4 hours.

[0044] Add 400g of 4% hydrochloric acid aqueous solution to the reaction system while keeping the system temperature below 30℃. Stir for 30 minutes. After completion, centrifuge to separate the solid and liquid, collect the solid, wash it with water several times, reflux it with ethanol once, wash it with water again, and dry it under reduced pressure at 150℃ for 5 hours to obtain polyether ketone ketone polymer.

[0045] According to ISO 307, its intrinsic viscosity in 96% sulfuric acid is 0.92 dL / g.

[0046] The obtained powder sample was molded into a test strip according to ISO 527 standard by molding, and its tensile strength was tested, with a result of 128 MPa.

[0047] ICP testing showed that the aluminum ion content in the powder sample was 41 PPM.

[0048] Scanning electron microscope (SEM) image of the obtained powder sample (see reference). Figure 1 As shown, the thermogravimetric analysis (TG) curves of the obtained powder samples are as follows: Figure 2 As shown.

[0049] Example 2

[0050] The entire reaction process was carried out using N2 as a protective gas. In a 1L reactor, the stirring device was turned on, and then 8.51g of diphenyl ether, 13.7g of terephthaloyl chloride and 400ml of dichloromethane were slowly added.

[0051] The temperature inside the entire reactor was lowered to -15℃. After the temperature stabilized, 32g of aluminum chloride was slowly added to the reactor. 30 minutes after the catalyst was added, the temperature of the reactor was raised to 30℃.

[0052] After reacting for 1 hour, 4.7 g of diphenyl ether was added to the reactor, and the temperature was maintained at 30°C for 2 hours.

[0053] Then, 0.01 g of benzoyl chloride was added to the reactor and the reaction was continued at 30°C for 4 hours.

[0054] Add 400g of 4% hydrochloric acid aqueous solution to the reaction system while keeping the system temperature below 30℃. Stir for 30 minutes. After completion, centrifuge to separate the solid and liquid, collect the solid, wash it with water several times, reflux it with ethanol once, wash it with water again, and dry it under reduced pressure at 150℃ for 5 hours to obtain polyether ketone ketone polymer.

[0055] According to ISO 307, its intrinsic viscosity in 96% sulfuric acid is 0.82 dL / g.

[0056] The obtained powder sample was molded into a test strip according to ISO 527 standard by molding, and its tensile strength was tested, with a result of 105 MPa.

[0057] ICP testing showed that the aluminum ion content in the powder sample was 40 PPM.

[0058] Example 3

[0059] The entire reaction process was carried out using N2 as a protective gas. In a 1L reactor, the stirring device was turned on, and then 8.51g of diphenyl ether, 20.3g of terephthaloyl chloride and 400ml of dichloromethane were slowly added.

[0060] The temperature inside the entire reactor was lowered to -10℃. After the temperature stabilized, 37.32g of aluminum chloride was slowly added to the reactor. 30 minutes after the catalyst was added, the temperature of the reactor was raised to 40℃.

[0061] After reacting for 1 hour, 8.51 g of diphenyl ether was added to the reactor, and the temperature was maintained at 30°C for 3 hours.

[0062] Then, 0.01 g of chlorobenzoyl chloride was added to the reactor and the reaction was continued at 30°C for 4 hours.

[0063] Add 400g of 4% hydrochloric acid aqueous solution to the reaction system while keeping the system temperature below 30℃. Stir for 30 minutes. After completion, centrifuge to separate the solid and liquid, collect the solid, wash it with water several times, reflux it with ethanol once, wash it with water again, and dry it under reduced pressure at 150℃ for 5 hours to obtain polyether ketone ketone polymer.

[0064] According to ISO 307, its intrinsic viscosity in 96% sulfuric acid is 0.88 dL / g.

[0065] The obtained powder sample was molded into a test strip according to ISO 527 standard by molding, and its tensile strength was tested, with a result of 110 MPa.

[0066] ICP testing showed that the aluminum ion content in the powder sample was 32 PPM.

[0067] Example 4

[0068] The entire reaction process was carried out using N2 as a protective gas. In a 1L reactor, the stirring device was turned on, and then 8.51g of diphenyl ether, 20.3g of terephthaloyl chloride and 400ml of dichloromethane were slowly added.

[0069] The temperature inside the entire reactor was lowered to -20°C. After the temperature stabilized, 37.32g of aluminum chloride was slowly added to the reactor. 30 minutes after the catalyst was added, the temperature of the reactor was raised to 30°C.

[0070] After reacting for 1 hour, 8.51 g of diphenyl ether was added to the reactor, and the temperature was maintained at 20°C for 3 hours.

[0071] Then, 0.01 g of benzoyl chloride was added to the reactor and the reaction was continued at 30°C for 1 hour.

[0072] Add 400g of 4% hydrochloric acid aqueous solution to the reaction system while keeping the system temperature below 30℃. Stir for 30 minutes. After completion, centrifuge to separate the solid and liquid, collect the solid, wash it with water several times, reflux it with methanol and ethanol once, wash it with water again, and dry it under reduced pressure at 150℃ for 5 hours to obtain polyether ketone ketone polymer.

[0073] According to ISO 307, its intrinsic viscosity in 96% sulfuric acid is 0.90 L / g.

[0074] The obtained powder sample was molded into a test strip according to ISO 527 standard by molding, and its tensile strength was tested, with a result of 112 MPa.

[0075] ICP testing showed that the aluminum ion content in the powder sample was 25 PPM.

[0076] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A method for preparing polyether ketone, characterized in that, include: Under nitrogen protection, terephthaloyl chloride and / or isophthaloyl chloride, diphenyl ether and polymer solvent are mixed and the low temperature is controlled at -20 to -5°C. During the stirring process, anhydrous aluminum chloride is added, and the temperature is raised to 10°C to 40°C and stirred for 0.1h to 1h to obtain a first mixed solution. The mass ratio of the amount of anhydrous aluminum chloride added to the mass ratio of diphenyl ether in the first mixed solution is 6:1 to 3:

1. In the first mixed solution, the mass ratio of terephthaloyl chloride and / or isophthaloyl chloride to diphenyl ether is 2.39:1 to 1.5:

1. Diphenyl ether is added to the first mixed solution, and the temperature is controlled at 25℃-40℃. The reaction is carried out for 0.1h-6h to obtain the second mixed solution. In the second mixed solution, the ratio of terephthaloyl chloride and / or isophthaloyl chloride to diphenyl ether is 1.3:1-1:1.

1. Add a capping agent and maintain the reaction at 25℃-40℃ for 1 to 4 hours to obtain a mixture of polyether ketone ketone products, wherein the capping agent is diphenyl ether, benzoyl chloride or p-chlorobenzoyl chloride; The polyether ketone ketone product mixture was added to an ice-cold acidic protic solution for quenching, and then filtered to obtain crude polyether ketone ketone solid. The crude polyether ketone ketone solid was washed with alcohol and ketone detergents, and then washed with water to obtain wet polyether ketone ketone solid. The wet polyether ketone solid was dried to obtain polyether ketone.

2. The method for preparing polyetherketone ketone according to claim 1, characterized in that, Let m be the mass of terephthaloyl chloride and / or isophthaloyl chloride and diphenyl ether in the second mixed solution, and let m be the mass of the capping agent be less than or equal to 0.87m.

3. The method for preparing polyether ketone ketone according to claim 1, characterized in that, The polymer solvent is one or a mixture of two or more of o-dichlorobenzene, dichloroethane, and dichloromethane.

4. The method for preparing polyetherketone ketone according to claim 1, characterized in that, The alcohol and ketone detergents mentioned are selected from methanol, ethanol, propanol or acetone.

5. The method for preparing polyether ketone ketone according to claim 1, characterized in that, The prepared polyether ketone contains aluminum metal residue in the range of 0-50 ppm and chloride ion content in the range of 0-100 ppm.

6. The method for preparing polyetherketone ketone according to claim 1, characterized in that, The drying temperature for wet polyether ketone solids is between 120℃ and 180℃.

7. A polyether ketone, characterized in that, The polyetherketone ketone is prepared by the method according to any one of claims 1 to 6.

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