Polyaryletherketone waste recovery method, polyaryletherketone and application of polyaryletherketone

Abstract

The invention provides a polyaryletherketone waste recovery method, polyaryletherketone and application thereof. The method comprises the following steps: (1) mixing the polyaryletherketone waste with a molten high-boiling-point organic solvent, heating and dissolving under first stirring, and continuing first stirring and heat preservation to obtain a clear solution; (2) cooling the clarified liquid to a first temperature, and continuing second stirring and heat preservation; and (3) continuously cooling the system obtained in the step (2) to a second temperature under the second stirring, and mixing with deionized water to obtain the polyaryletherketone. The method is simple in process and high in production efficiency, and the obtained polyaryletherketone is small in grain, good in stability, high in purity and excellent in mechanical property.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a polyaryletherketone waste recovery method, polyaryletherketone and application thereof. Background Art

[0002] Polyaryletherketone (PAEK) has stable chemical properties and excellent comprehensive properties such as high temperature resistance, self-lubrication, flame retardancy, hydrolysis resistance, wear resistance and fatigue resistance. It is widely used in industrial manufacturing, aerospace, automotive industry, 3D printing industry, electronic and electrical and medical equipment. Due to the high price of polyaryletherketone, recycling and reuse of polyaryletherketone also has high economic value. Through effective recycling technology, waste polyaryletherketone can be remade into high-performance plastic products, reducing production costs while achieving efficient use of resources.

[0003] At present, the main methods for recycling polyaryletherketone are: (1) Mechanical recycling: Process the waste into particles or powders by crushing, grinding, etc., and separate PAEK from other impurities by filtering, centrifuging, etc. This method is suitable for the recycling of PAEK with low impurity content, but the processing efficiency is low. (2) Melting recycling: Heat the waste PAEK products to the melting point, and then produce new PAEK products through processes such as extrusion molding and injection molding. This method is suitable for the recycling of high-purity PAEK, but may be affected by cost and energy consumption. (3) Biodegradation recycling: Use microorganisms to decompose waste PAEK into simple compounds, such as alcohols, acids, etc., and then extract pure PAEK by distillation or other methods. This method is suitable for the recycling of low-concentration PAEK, but it may take a long time to complete the degradation process. Therefore, the existing polyaryletherketone recycling methods need to be improved. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the prior art at least to a certain extent. To this end, one object of the present invention is to provide a polyaryletherketone waste recycling method, polyaryletherketone and application thereof.

[0005] In a first aspect of the present invention, the present invention provides a method for recycling polyaryletherketone waste. According to an embodiment of the present invention, the method comprises: S10: Mix the polyaryletherketone waste with the molten high-boiling point organic solvent, heat and dissolve it under the first stirring, and then continue the first stirring and heat preservation

[0006] In this step, the polyaryletherketone waste material is mixed with a molten high-boiling point organic solvent and then heated and dissolved under a first stirring condition to obtain a clarified liquid. After the polyaryletherketone waste material is dissolved, the first stirring and heat preservation are continued, so that the molecular chain segments of the polyaryletherketone after the dissolution are slowly arranged and recrystallized. The molten high-boiling point organic solvent dissolves the polyaryletherketone but does not destroy its chemical structure, that is, the sulfonation phenomenon of the polyaryletherketone dissolved in concentrated sulfuric acid does not occur, and the mechanical properties, thermal stability and solvent resistance of the polyaryletherketone can be retained to the maximum extent.

[0007] It should be noted that polyaryletherketone waste includes waste generated by polyaryletherketone resin injection molding process, grinding process, and mechanical processing process. According to the type, polyaryletherketone waste includes one of polyetheretherketone waste, polyetherketone waste, polyetherketoneketone waste, polyetheretherketoneketone waste, and polyetherketoneetherketoneketone waste. And the present application does not specifically limit the shape of polyaryletherketone waste, for example, polyaryletherketone waste includes but is not limited to powder, granules, flakes or blocks. Generally, polyaryletherketone waste is controlled within a suitable particle size range, which is more conducive to the dissolution of polyaryletherketone waste.

[0008] At the same time, the present application does not make any special requirements on the impurity content in the polyaryletherketone waste. The method of the present application is applicable to polyaryletherketone waste with low impurity content and high purity, and is also applicable to polyaryletherketone waste with high impurity content and low purity. For example, the impurity content in the polyaryletherketone waste is not less than 1wt%, and for example, the impurity content is 2wt%, 5wt%, 8wt%, 10wt%, 15wt%, 20wt%, etc.

[0009] Preferably, the melting temperature of the high boiling point organic solvent is not less than 150° C., so that the polyaryletherketone can be fully dissolved.

[0010] In some embodiments of the present invention, the high boiling point organic solvent includes at least one of 1,2,3-triphenylbenzene, diphenyl sulfone, 4,4'-dibromobiphenyl and terphenyl.

[0011] In some embodiments of the present invention, the temperature of the first stirring and heat preservation is 280°C-310°C, and the time is 1h-3h. For example, the temperature is 280°C, 285°C, 290°C, 295°C, 300°C, 305°C, 310°C, etc., or the range between any two of the above values; the time is 1h, 1.5h, 2h, 2.5h, 3h, etc., or the range between any two of the above values. The inventors have found that the temperature of the first stirring and heat preservation is within the above range, which can maintain the dissolved state of polyaryletherketone, and at the same time, controlling the time within the above range can make the molecular segments of polyaryletherketone slowly arranged and recrystallized, which is beneficial to improve the mechanical properties and stability of polyaryletherketone.

[0012] In some embodiments of the present invention, the first stirring speed is 300 rpm-500 rpm. For example, the first stirring speed is 300 rpm, 350 rpm, 400 rpm, 450 rpm, 500 rpm, etc., or a range between any two of the above values.

[0013] In some embodiments of the present invention, the volume of the molten high-boiling point organic solvent is a mL, the mass of the polyaryletherketone waste is bg, and a:b is not less than 3, thereby providing more high-boiling point organic solvent to ensure that the polyaryletherketone waste is completely dissolved.

[0014] S20: Cool the clarified liquid to the first temperature and continue the second stirring and heat preservation

[0015] In this step, by cooling the clarified liquid obtained after the insulation in S10 to the first temperature and continuing the second stirring insulation, the polyaryletherketone molecules can be slowly rearranged in the solvent, and the polyaryletherketone crystals can be nucleated and grown. The second stirring can break up the formed large particles, increase the solute diffusion rate, promote crystal growth, and form polyaryletherketone with uniform particle size, thereby improving the stability of the polyaryletherketone.

[0016] In some embodiments of the present invention, the first temperature is 250°C-265°C. For example, the first temperature is 250°C, 255°C, 260°C, 265°C, etc., or a range between any two of the above values. The inventors have found that by controlling the first temperature within the above range, the growth rate of the polyaryletherketone crystal is slow, the nucleation density of the crystal in the solution is increased, and crystalline particles with uniform particle size can be obtained, thereby improving the stability of the polyaryletherketone.

[0017] In some embodiments of the present invention, the cooling rate of the clarified liquid to the first temperature is 1°C / min-10°C / min. For example, the cooling rate is 1°C / min, 3°C / min, 5°C / min, 7°C / min, 10°C / min, etc., or a range between any two of the above values. By controlling the cooling rate within the above range, polyaryletherketone particles with uniform particle size are prepared.

[0018] In some embodiments of the present invention, the second stirring and heat preservation time is 3h-6h. For example, the second stirring and heat preservation time is 3h, 4h, 5h, 6h, etc., or a range between any two of the above values. By controlling the second stirring and heat preservation time within the above range, the polyaryletherketone molecular chain can be fully rearranged and crystallized.

[0019] In some embodiments of the present invention, the second stirring speed is 600rpm-1200rpm. For example, the second stirring speed is 600rpm, 700rpm, 800rpm, 900rpm, 1000rpm, 1100rpm, 1200rpm, etc., or a range between any two of the above values. By controlling the second stirring speed within the above range, the formed polyaryletherketone crystal particles can be broken, the solute diffusion rate is increased, the crystal growth is promoted, and a polyaryletherketone with a smaller particle size and uniformity is formed, thereby improving the stability of the polyaryletherketone.

[0020] S30: The system obtained in S20 is further cooled to a second temperature under the second stirring and then mixed with deionized water

[0021] In this step, the system obtained in S20 is further cooled to the second temperature under the second stirring and then mixed with deionized water. By continuing the second stirring and cooling, the polyaryletherketone in the solution can be precipitated on the surface of the already formed microparticles. After the temperature is reduced to the second temperature and mixed with deionized water, the impurities in the polyaryletherketone waste material and the polyaryletherketone matrix can be phase-separated to obtain pure polyaryletherketone.

[0022] In some embodiments of the present invention, the obtained polyaryletherketone powder can be washed and centrifuged in sequence to obtain a recovered pure polyaryletherketone powder, and then vacuum dried. The washing agent can be acetone or ethanol, the centrifugal speed is 6000-10000 rpm, the drying temperature is 60-120°C, and the drying time is 4-10 hours.

[0023] In some embodiments of the present invention, the second temperature is 210° C.-220° C. For example, the second temperature is 210° C., 212° C., 215° C., 217° C., 220° C., etc., or a range between any two of the above values. By controlling the second temperature within the above range, polyaryletherketone can be precipitated, thereby improving the precipitation efficiency and purity of polyaryletherketone.

[0024] In some embodiments of the present invention, the cooling rate to the second temperature is 1°C / min-10°C / min. For example, the cooling rate is 1°C / min, 3°C / min, 5°C / min, 7°C / min, 10°C / min, etc., or a range between any two of the above values.

[0025] In a second aspect of the present invention, a polyaryletherketone is provided. According to an embodiment of the present invention, the polyaryletherketone is recovered by the above method. Thus, the polyaryletherketone has excellent mechanical properties, thermal stability and solvent resistance, and the polyaryletherketone has high purity.

[0026] In some embodiments of the present invention, the particle size of the polyaryletherketone is 20 μm-30 μm.

[0027] In the third aspect of the present invention, the present invention proposes the application of the above-mentioned polyaryletherketone in the fields of industrial manufacturing, aerospace, automobile industry, 3D printing, electronic and electrical fields or medical devices.

[0028] The present invention has at least the following technical effects: (1) The present application can make waste polyaryletherketone into high-performance polyaryletherketone products. The recovery rate of polyaryletherketone is greater than 90%. The recovery and reuse of polyaryletherketone helps to reduce the generation of waste, alleviate the pressure on the environment, reduce production costs and achieve efficient utilization of resources.

[0029] (2) The chemical structure of the polyaryletherketone prepared in the present application is not destroyed, the polyaryletherketone has small grains, good stability, high purity, and excellent mechanical properties.

[0030] (3) The polyaryletherketone waste recycling method of the present application has a simple process, high production efficiency, low cost, and no requirements on the molecular weight of the polyaryletherketone, and is suitable for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 is a scanning electron microscope image of the polyetheretherketone powder of Example 1 of the present invention; Figure 2 is a scanning electron microscope image of the polyetheretherketone powder of Example 2 of the present invention; Figure 3 is a scanning electron microscope image of the polyetheretherketone powder of Example 6 of the present invention; Figure 4 This is a comparison chart of infrared spectra of polyetheretherketone of Example 1 of the present invention and commercially available pure polyetheretherketone; Figure 5 It is a comparison diagram of the DSC curves of the polyetheretherketone of Example 1 of the present invention and commercially available pure polyetheretherketone. DETAILED DESCRIPTION

[0033] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0034] Example 1

[0035] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. Place the three-necked flask in an electric heating mantle, heat diphenyl sulfone to 200°C to melt and form a diphenyl sulfone solution, add 100g of polyetheretherketone resin waste powder (the particle size of polyetheretherketone resin waste powder is 10μm~2mm) and dissolve it in 300mL of diphenyl sulfone. Pass nitrogen, exhaust the air in the reaction vessel, heat to 290°C while stirring, and continue to keep warm and stir for 2h after the powder is completely dissolved, with a stirring speed of 300rpm. At this time, a clear solution of polyetheretherketone resin can be observed, but because the added polyetheretherketone waste powder contains impurities such as dust, the solution color is black. After the insulation is completed, slowly drop to 265°C, with a cooling rate of 10°C / min. After the system becomes turbid, stir rapidly for 4h at a stirring speed of 800rpm. Subsequently, the system was slowly cooled to 220°C at a cooling rate of 10°C / min, poured into deionized water, and the impurities were separated from the PEEK resin by a thermally induced phase separation process to obtain a recovered white PEEK product. The product was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 8000rpm, dried in a vacuum oven at 80°C for 4h, and the recovered polyetheretherketone powder was obtained.

[0036] Example 2

[0037] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. Place the three-necked flask in an electric heating mantle, heat diphenyl sulfone to 200°C to melt and form a diphenyl sulfone solution, and dissolve 100g of polyetheretherketone resin waste particles (the particle size of polyetheretherketone resin waste particles is 2mm~5mm) in 300mL of diphenyl sulfone solution. Pass nitrogen, exhaust the air in the reaction vessel, heat to 285°C while stirring, and continue to keep warm and stir for 2h after the powder is dissolved, with a stirring speed of 300rpm. Compared with Example 1, the solution of polyetheretherketone resin is yellow and transparent. After the insulation is completed, slowly drop to 255°C, with a cooling rate of 10°C / min. After the system becomes turbid, stir rapidly for 4h at a stirring speed of 800 rpm. Subsequently, the system was slowly cooled to 210°C at a cooling rate of 10°C / min, and poured into deionized water to obtain a recovered white PEEK product. The product was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 8000 rpm, dried in a vacuum oven at 80°C for 4 hours, and recovered polyetheretherketone powder was obtained.

[0038] Example 3

[0039] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. The three-necked flask is placed in an electric heating mantle, and the diphenyl sulfone is heated to 200°C. The diphenyl sulfone melts to form a diphenyl sulfone solution, and 100g of polyetheretherketone resin waste blocks (the side length of the polyetheretherketone resin waste blocks is: 5mm~10mm) are dissolved in 300mL of diphenyl sulfone solution. Nitrogen is introduced to exhaust the air in the reaction vessel, and the temperature is raised to 290°C while stirring. After the powder is dissolved and becomes a clear solution, continue to keep warm and stir for 1h at a stirring speed of 400rpm. After the insulation is completed, slowly drop to 265°C at a cooling rate of 5°C / min. After the system becomes turbid, stir rapidly for 4h at a stirring speed of 800rpm. Subsequently, the system is slowly cooled to 220°C at a cooling rate of 5°C / min, poured into deionized water, and a recovered white PEEK product is obtained. The mixture was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 10,000 rpm and dried in a vacuum oven at 80° C. for 4 h to obtain recovered polyetheretherketone powder.

[0040] Example 4

[0041] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. The three-necked flask is placed in an electric heating mantle, and the diphenyl sulfone is heated to 200°C. The diphenyl sulfone melts to form a diphenyl sulfone solution, and 100g of polyetheretherketone resin waste silk (the length of the polyetheretherketone resin waste silk is 10mm~20mm, and the diameter is 1mm~3mm) is dissolved in 300mL of diphenyl sulfone solution. Nitrogen is introduced to exhaust the air in the reaction vessel, and the temperature is raised to 290°C while stirring until the powder dissolves and becomes a clear solution. Continue to keep warm and stir for 2h at a stirring speed of 400rpm. After the insulation is completed, it is slowly reduced to 265°C at a cooling rate of 1°C / min. After the system becomes turbid, it is quickly stirred for 4h at a stirring speed of 800rpm. Subsequently, the system is slowly cooled to 220°C at a cooling rate of 1°C / min, and poured into deionized water to obtain a recovered white PEEK product. The product was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 10,000 rpm and dried in a vacuum oven at 80°C for 4 h to obtain recovered polyetheretherketone powder.

[0042] Example 5

[0043] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. Place the three-necked flask in an electric heating jacket, heat diphenyl sulfone to 200°C to melt and form a diphenyl sulfone solution, and dissolve 100g of polyetheretherketone resin waste powder in 400mL of diphenyl sulfone solution. Pass nitrogen, exhaust the air in the reaction vessel, heat to 280°C while stirring, and continue to keep warm and stir for 2h after the polyetheretherketone powder is dissolved, with a stirring speed of 400rpm. After the insulation is completed, slowly drop to 265°C, with a cooling rate of 10°C / min. After the system becomes turbid, stir rapidly for 4h, with a stirring speed of 800rpm. Subsequently, the system is slowly cooled to 220°C, with a cooling rate of 10°C / min, and poured into deionized water. The mixture was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 10,000 rpm and dried in a vacuum oven at 80° C. for 4 h to obtain recovered polyetheretherketone powder.

[0044] Example 6

[0045] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. Place the three-necked flask in an electric heating jacket, heat diphenyl sulfone to 200°C to melt and form a diphenyl sulfone solution, and dissolve 100g of polyetheretherketone resin waste powder in 250mL of diphenyl sulfone solution. Pass nitrogen to exhaust the air in the reaction vessel, heat to 290°C while stirring, and continue to keep warm and stir for 2h after the powder is completely dissolved, with a stirring speed of 400rpm. At this time, a clear solution of polyetheretherketone resin can be observed, but due to the addition of polyetheretherketone waste powder, the solution contains impurities such as dust and is black in color. After the insulation is completed, slowly drop to 265°C, with a cooling rate of 10°C / min. After the system becomes turbid, stir rapidly for 4h at a stirring speed of 800rpm. Subsequently, the system was slowly cooled to 220°C at a cooling rate of 10°C / min, poured into deionized water, and the impurities were separated from the PEEK resin by a thermally induced phase separation process to obtain a recovered white PEEK product. The product was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 8000rpm, dried in a vacuum oven at 80°C for 4h, and the recovered polyetheretherketone powder was obtained.

[0046] Example 7

[0047] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. Place the three-necked flask in an electric heating mantle, heat the terphenyl to 210°C to form a terphenyl solution, and dissolve 100g of polyetheretherketone resin waste sheets (polyetheretherketone resin waste sheets have a length of 10mm~15mm, a width of 5mm~8mm, and a thickness of 1mm~2mm) in 300mL of terphenyl solution. Pass nitrogen, exhaust the air in the reaction vessel, and heat to 290°C while stirring. After the polyetheretherketone resin is dissolved and becomes a clear solution, continue to keep warm and stir for 1h at a stirring speed of 400rpm. After the insulation is completed, slowly drop to 255°C at a cooling rate of 5°C / min. After the system becomes turbid, stir rapidly for 4h at a stirring speed of 800rpm. Subsequently, the system was slowly cooled to 210°C at a cooling rate of 5°C / min, and poured into deionized water to obtain a recovered white PEEK product. The product was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 8000 rpm and dried in a vacuum oven at 70°C for 5 hours to obtain a recovered polyetheretherketone powder.

[0048] Example 8

[0049] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. Place the three-necked flask in an electric heating mantle, heat 1,2,3-triphenylbenzene to 160°C to form a solution, and dissolve 100g of polyetheretherketone resin waste strips (polyetheretherketone resin waste strips have a length of 15mm~22mm, a width of 10mm-15mm, and a thickness of 5mm-10mm) in 300mL of 1,2,3-triphenylbenzene solution. Pass nitrogen to exhaust the air in the reaction vessel, heat to 280°C while stirring, and continue to heat and stir for 2h after the polyetheretherketone is dissolved, with a stirring speed of 400rpm. After the insulation is completed, slowly drop to 255°C, with a cooling rate of 10°C / min. After the system becomes turbid, stir rapidly for 4h at a stirring speed of 800rpm. Subsequently, the system was slowly cooled to 220°C at a cooling rate of 10°C / min, and poured into deionized water to obtain a recovered white PEEK product. The product was washed with acetone, centrifuged three times, and finally washed with deionized water at a centrifugal speed of 10,000 rpm, and dried in a vacuum oven at 70°C for 5 hours to obtain a recovered polyetheretherketone powder.

[0050] Comparative Example 1

[0051] In a three-necked flask equipped with a stirrer, one side is connected to a three-way connection to place a thermometer and a high-purity nitrogen inlet, and the other side is connected to a spherical condenser for exhaust. Place the three-necked flask in an electric heating mantle, heat diphenyl sulfone to 200°C to melt and form a diphenyl sulfone solution, and dissolve 100g of polyetheretherketone resin waste powder in 300mL of diphenyl sulfone solution. Pass nitrogen to exhaust the air in the reaction vessel, heat to 290°C while stirring, and continue to keep warm and stir for 2h at a stirring speed of 400rpm, then cool directly to crush the PEEK powder.

[0052] The polyetheretherketone powders prepared in Example 1, Example 2 and Example 6 were subjected to electron microscope scanning, and the specific results are shown in Figure 1 , Figure 2 and Figure 3 The scale bar in the figure is 100μm. Figure 1 and Figure 2 It can be seen that the particle size of the polyetheretherketone powder is less than 30μm, and the surface morphology of the powder is relatively complete. This is because the solvent selected by the present invention can completely dissolve the polyetheretherketone waste, and the appropriate temperature and cooling temperature are controlled to make the polyetheretherketone resin molecular chain move slowly, rearrange and crystallize. When the temperature is low, the crystal growth slows down, the crystal nucleus density increases, and the average particle size of the recovered PEEK powder becomes smaller. Figure 3 It can be seen that the amount of solvent used in Example 6 is relatively small and cannot completely dissolve polyetheretherketone, and the prepared recycled powders are adhered to each other.

[0053] The average particle size, recovery rate and purity of the polyetheretherketone prepared in Examples 1-8 and Comparative Example 1 are shown in Table 1.

[0054] Table 1

[0055] Recovery rate = recovered PEEK mass / initial PEEK mass, where the initial PEEK mass refers to the mass of PEEK resin waste; It can be seen from Table 1 that the particle size of the polyetheretherketone obtained in the present application is between 20 μm and 30 μm, and the recovery rate is greater than 90%.

[0056] The infrared spectra of the polyetheretherketone prepared in Example 1 and the commercially available pure polyetheretherketone are compared as shown in the figure below: Figure 4 As shown, from Figure 4 It can be seen that the polyetheretherketone material of Example 1 has a -1 and 1225cm -1 It shows the characteristic peaks of C=0 and COC in PEEK.

[0057] Comparison of DSC curves of polyetheretherketone prepared in Example 1 and commercially available pure polyetheretherketone Figure 5As shown, the crystallinity of pure PEEK is 26-35%. Figure 5 It can be seen that the crystallinity of commercially pure PEEK is 34.7%, and the crystallinity of the polyetheretherketone in Example 1 is 29.9%, indicating that the crystallinity of the polyetheretherketone of the present invention is within 26-35%, and high-purity polyetheretherketone can be prepared by the method of the present invention.

[0058] The tensile properties of Examples 1-8, Comparative Example 1 and commercially available polyetheretherketone were tested as follows: According to the national standard GB / T 1040.1-2018 Determination of tensile properties of plastics Part 1: General, the tensile properties of commercially available pure PEEK, Examples 1-8, and polyetheretherketone recovered in Comparative Example 1 were tested.

[0059] The tensile property test results of Examples 1-8, Comparative Example 1 and commercially available polyetheretherketone are shown in Table 2.

[0060] Table 2

[0061] From the data in Table 2, it can be seen that the polyetheretherketone waste recycled in this application is used to prepare polyetheretherketone, and the tensile properties of polyetheretherketone reach more than 80% of the tensile properties of pure polyetheretherketone resin, thereby retaining the mechanical properties of polyetheretherketone to the greatest extent.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for recycling polyaryletherketone waste, characterized in that: include: (1) mixing the polyaryletherketone waste with a molten high-boiling point organic solvent, heating and dissolving the mixture under a first stirring condition, and then continuing the first stirring and heat preservation to obtain a clarified liquid; (2) cooling the clarified liquid to the first temperature and then continuing the second stirring and heat preservation; (3) The system obtained in step (2) is further cooled to a second temperature under the second stirring condition and then mixed with deionized water to obtain polyaryletherketone.

2. The method according to claim 1, characterized in that: In step (1), the temperature of the first stirring and heat preservation is 280°C-310°C, and the time is 1h-3h; And / or, the first stirring rotation speed is 300rpm-500rpm.

3. The method according to claim 1 or 2, characterized in that: In step (1), the melting temperature of the high boiling point organic solvent is not less than 150°C; And / or, the high boiling point organic solvent includes at least one of 1,2,3-triphenylbenzene, diphenyl sulfone, 4,4'-dibromobiphenyl and terphenyl; And / or, the volume of the molten high-boiling point organic solvent is a mL, the mass of the polyaryletherketone waste is bg, and a:b is not less than 3.

4. The method according to claim 1 or 2, characterized in that: In step (1), the polyaryletherketone waste includes one of polyetheretherketone waste, polyetherketone waste, polyetherketoneketone waste, polyetheretherketoneketone waste, and polyetherketoneetherketoneketone waste.

5. The method according to claim 1, characterized in that: In step (2), the first temperature is 250°C-265°C; And / or, the cooling rate of the clarified liquid to the first temperature is 1°C / min-10°C / min.

6. The method according to claim 1 or 5, characterized in that: In step (2), the second stirring and heat preservation time is 3h-6h; And / or, the second stirring speed is 600 rpm-1200 rpm.

7. The method according to claim 1 or 2, characterized in that: In step (3), the second temperature is 210°C-220°C; And / or, the cooling rate to the second temperature is 1°C / min-10°C / min.

8. A polyaryletherketone, characterized in that The product is recovered by the method described in any one of claims 1 to 7.

9. The polyaryletherketone according to claim 8, characterized in that: The particle size of the polyaryletherketone is 20 μm-30 μm.

10. Use of the polyaryletherketone according to claim 8 or 9 in the industrial manufacturing field, aerospace field, automobile industry field, 3D printing field, electronic and electrical field or medical device field.

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