Polyether-ether-ketone-based fiber as well as preparation method and application thereof

Abstract

The invention discloses a polyether-ether-ketone-based fiber as well as a preparation method and application thereof. The polyether-ether-ketone-based fiber comprises polyether-ether-ketone, polyether sulfone and thermotropic liquid crystal polyarylester. According to the invention, the spinning temperature of the polyether-ether-ketone resin can be reduced by 40-50 DEG C, and the basic mechanical properties and heat resistance of the polyether-ether-ketone fiber are not affected. After the spinning temperature is reduced, the energy consumption of spinning equipment can be obviously reduced, the failure rate of electric heating equipment is reduced, and the rejection cycle of the spinneret plate is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of polymer processing, and in particular to a polyetheretherketone-based fiber and a preparation method and application thereof. Background Art

[0002] Polyetheretherketone (PEEK) is a high-temperature resistant thermoplastic polymer. Currently, high-temperature melt spinning is generally used, and then high-temperature slow stretching and heat setting are used to prepare polyetheretherketone fibers. Due to its high melting point of 344°C, its spinning temperature usually needs to reach 390-420°C, so the spinning process has high energy consumption and high requirements for spinning equipment (especially spinneret material).

[0003] In order to reduce the spinning temperature, the usual practice is to use raw materials with lower average molecular weight or add plasticizers to the raw materials. However, fibers made from polyetheretherketone raw materials with lower average molecular weight often have lower tensile strength, and lose or even lose their original performance. The added plasticizer must maintain sufficient stability at the spinning temperature and cannot decompose or gasify. At present, no plasticizer has been found whose operating temperature can match the spinning temperature range of polyetheretherketone.

[0004] Therefore, there is an urgent need to address the problems of high spinning temperature, high energy consumption, high equipment cost and high loss of polyetheretherketone resin in the prior art, and to provide a new type of polyetheretherketone-based fiber that only requires lower spinning temperature, lower energy consumption and lower equipment cost. Summary of the invention

[0005] In order to solve the problems of high spinning temperature, high energy consumption, high equipment cost and high loss of polyetheretherketone resin in the prior art, the present invention provides a polyetheretherketone-based fiber and a preparation method and application thereof. The present invention aims to reduce the spinning temperature of polyetheretherketone resin, reduce energy consumption, reduce equipment cost and loss, so that the polyetheretherketone-based fiber has a lower cost while maintaining the original high temperature resistance and mechanical properties.

[0006] One of the purposes of the present invention is to provide a polyetheretherketone-based fiber, including polyetheretherketone, polyethersulfone and thermotropic liquid crystal polyarylate. In the present invention, since general plasticizers cannot withstand the spinning temperature range of polyetheretherketone, it is preferred that no organic additives including organic plasticizers are added to the polyetheretherketone-based fiber of the present invention during spinning. Since the polyetheretherketone-based fiber of the present invention is based on a polymer, it is also preferred that no inorganic additives are added.

[0007] In a preferred embodiment of the present invention,

[0008] The melt index of the polyetheretherketone is (380°C, 5Kg) 20-100g / 10min, preferably 30-50g / 10min; polyetheretherketone is a high temperature resistant thermoplastic semi-crystalline polymer with a melting point of 334-400°C and a glass transition temperature of 135-160°C; and / or,

[0009] The melt index of the polyethersulfone is (380°C, 5Kg) 10-80g / 10min, preferably 60-80g / 10min; polyethersulfone (PES) is also a high temperature resistant thermoplastic polymer material, with a long-term use temperature of 180-220°C. PES is a completely amorphous polymer with no melting point. The addition of a small amount of polyethersulfone can destroy the molecular regularity of polyetheretherketone and reduce the intermolecular force, thereby reducing the melt viscosity of the system; and / or,

[0010] The melting temperature of the thermotropic liquid crystal polyarylate is above 250°C, preferably above 270°C, and further preferably 270-350°C. Thermotropic liquid crystal polyarylate (TLCP) has excellent mechanical and rheological properties. Adding a small amount of thermotropic liquid crystal polyarylate to PEEK can effectively reduce its melt viscosity, and at the same time can effectively improve the mechanical properties of the PEEK / PES composite system by utilizing the in-situ microfiber reinforcement effect.

[0011] In a preferred embodiment of the present invention,

[0012] Based on the total weight of the polyetheretherketone-based fiber as 100%, the content of the polyetheretherketone is 80-98%, for example, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or any intermediate value between two values, and the content of the polyethersulfone is 1-10%, for example, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59%, 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 80%, %, 7%, 8%, 9%, 10% or any intermediate value between two values, the content of thermotropic liquid crystal polyarylate is 1-10%, for example, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10% or any intermediate value between two values, etc.; preferably, based on the total weight of the polyetheretherketone-based fiber as 100%, the content of polyetheretherketone is 90-94%, the content of polyethersulfone is 3-5% and the content of thermotropic liquid crystal polyarylate is 3-5%.

[0013] In a preferred embodiment of the present invention,

[0014] The polyetheretherketone-based fiber has a fineness of 2.0-10.0 dtex, preferably 3.3-6.7 dtex, and / or a breaking strength of 3.0-7.0 cN / dtex, preferably 3.5-6.0 cN / dtex.

[0015] In a preferred embodiment of the present invention,

[0016] The polyetheretherketone-based fiber is prepared by a preparation method comprising the step of melt-spinning components including polyetheretherketone, polyethersulfone and thermotropic liquid crystal polyarylate.

[0017] The second object of the present invention is to provide a method for preparing polyetheretherketone-based fibers according to one of the objects of the present invention, comprising the step of melt-spinning components including polyetheretherketone, polyethersulfone and thermotropic liquid crystal polyarylate.

[0018] In a preferred embodiment of the present invention,

[0019] The melting device is a screw extruder; preferably,

[0020] The screw extruder is at least one of a single-screw extruder and a twin-screw extruder; and / or,

[0021] The temperature of each zone of the screw of the screw extruder is 320-385°C, preferably 320-370°C.

[0022] In a preferred embodiment of the present invention,

[0023] The spinning conditions include: a spinning temperature of 350-395°C, preferably 360-385°C, for example 360°C, 365°C, 370°C, 375°C, 380°C, 385°C or an intermediate value between any two values, more preferably 360-370°C; and / or a spinning speed of 300-800m / min, preferably 500-800m / min, for example 500m / min, 550m / min, 600m / min, 650m / min, 700m / min, 750m / min, 800m / min or an intermediate value between any two values; and / or a stretching ratio of 2.0-4.0 times, preferably 3.0-3.5 times; and / or a heat setting temperature of 220-270°C, preferably 250-270°C.

[0024] In a preferred embodiment of the present invention,

[0025] Before melt spinning, the method further includes drying the polyetheretherketone, polyethersulfone and / or thermotropic liquid crystal polyarylate; preferably, the drying is vacuum drying; more preferably, the vacuum drying temperature is 140-160°C, and / or the vacuum drying time is greater than or equal to 10 hours, preferably 10-12 hours.

[0026] The present invention can adopt the following specific technical solutions:

[0027] 1-10% of polyethersulfone slices (or powder) and 1-10% of thermotropic liquid crystal polyarylate are added to the polyetheretherketone raw material. After the three raw materials are dried, they are melted by a single screw or twin screw extruder, and the temperature of each zone of the screw can be controlled at 320-385°C. Then they enter the spinning assembly for spinning. The spinning box adopts the form of electric heating, the spinning temperature can be controlled at 350-395°C, and the spinning speed can reach 300-800m / min. After 2.0-4.0 times stretching and 220-270°C heat setting, filaments with a fineness of 2.0-10.0dt can be obtained, and the breaking strength reaches 3.5-6.0cN / dt.

[0028] The structure of the spinning assembly used in the preparation method of the polyetheretherketone-based fiber is a common spinning assembly structure in the art, generally including a metering pump, a filter screen, a spinneret, etc., and is not specifically limited in the present invention.

[0029] The third object of the present invention is to provide a polyetheretherketone-based fiber of the first object of the present invention or a polyetheretherketone-based fiber obtained by the preparation method of the second object of the present invention. Application in the field of composite materials, preferably in high temperature resistant composites Application in the field of composite materials. Under high temperature conditions, the polyetheretherketone-based fibers of the present invention can be used alone or made into composite materials, especially in conveyor belts under high temperature conditions (such as various conveyor belts required in papermaking, textile printing, fabric heat setting, non-woven fabric bonding and food processing), filter screens, high-temperature gas filter felts, and high-performance canvas, cable covering materials, sporting goods, and composite materials for aviation.

[0030] When spinning polyetheretherketone, adding polyethersulfone and thermotropic liquid crystal polyarylate can obtain better fluidity at a lower temperature, thereby reducing the spinning temperature of the system and maintaining higher mechanical properties of the obtained fiber. The advantage of polyethersulfone and thermotropic liquid crystal polyarylate over other polymers is that they have better heat resistance and can withstand the heating process of polyetheretherketone spinning without obvious thermal degradation, so the two become "polymer plasticizers" that can reduce the spinning temperature of polyetheretherketone.

[0031] The invention can reduce the spinning temperature of polyetheretherketone resin by 40-50°C without affecting the basic mechanical properties and heat resistance of polyetheretherketone fiber. After the spinning temperature is reduced, the energy consumption of the spinning equipment can be significantly reduced, the failure rate of the electric heating equipment can be reduced, and the scrapping cycle of the spinneret can be extended. DETAILED DESCRIPTION

[0032] The present invention is described in detail below in conjunction with specific embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0033] Unless otherwise specified, the raw materials used in the examples and comparative examples of the present invention are all disclosed in the prior art, for example, they can be directly purchased or prepared according to the preparation methods disclosed in the prior art.

[0034] Test method:

[0035] Tensile breaking strength: test method refers to GB / T 14344-2008;

[0036] Denier: Test method refers to GB / T 14343-2008;

[0037] Decomposition temperature: The test method is thermogravimetric analysis, the instrument used is TG / DTA6300, Selko InstrumentsIno, and the test conditions are: heating rate 10°C / min (TG), nitrogen atmosphere, nitrogen flow rate 50-80mL / min.

[0038] Melt index: XNR-450 melt flow rate meter (Changchun Yueming Small Testing Machine Co., Ltd.) was used. The test conditions were: capillary diameter 2.095 mm, tube length 8 mm, and the weight of the test sample extruded within 10 minutes at 380°C and 5 kg was weighed.

[0039] In the embodiments and comparative examples of the present invention, each spinning process is continuously adjusted to find the most suitable spinning temperature and spinning speed. The final spinning temperature is the temperature that can reach the maximum spinning speed (that is, the most suitable spinning temperature), and the marked spinning speed is the maximum spinning speed.

[0040] Comparative Example 1

[0041] PEEK 381G (melt index of 42g / 10min under 380℃, 5Kg test conditions) produced by Victrex was used as raw material, dried at 160℃ for 12 hours in a vacuum drum dryer, added to a screw extruder (SHJ-18 produced by Nanjing Jieente Company) for melt extrusion, and the temperature of each zone of the screw was set at 345-400℃ (1st section 345℃, 2nd section 355℃, 3rd section 365℃, 4th section 380℃, 5th section 400℃), and then entered the spinning assembly, the spinning temperature was set to 400℃, and a cooling ring was configured under the spinneret (36 holes), the cooling ring temperature was set to 300℃, and the spinning speed was 500m / min to obtain PEEK primary fiber. After 24 hours of equilibrium, stretching heat setting was carried out, the temperature of the stretching hot box was 270℃, the stretching speed was 200m / min, and the multiple was 3.0. The obtained PEEK fiber has a fineness of 5.7 dtex, a single-filament breaking strength of 5.0 cN / dtex, and an initial decomposition temperature in air of 560°C (TG).

[0042] Example 1

[0043] PEEK 381G slices produced by Victrex were dried in a vacuum drum dryer at 160°C for 12 hours. PES E1010 produced by BASF (under the conditions of 380°C and 5Kg, the melt index was 68g / 10min) and TLCP produced by Ticona were dried in a vacuum drum dryer at 160°C for 12 hours. VectraA950 (melting temperature 280℃) was dried at 140℃ in a vacuum drum dryer for 12 hours, PEEK was mixed with PES and TLCP in a ratio of 98:1:1 (by weight), and melted and extruded in a screw extruder (SHJ-18 produced by Nanjing Jieente Company), and the temperature of each zone of the screw was set at 340-385℃ (1st section 340℃, 2nd section 350℃, 3rd section 365℃, 4th section 375℃, 5th section 385℃), and then entered the spinning assembly, and the spinning temperature was set to 395℃. A cooling ring was configured under the spinneret (36 holes), and the cooling ring temperature was set to 300℃. The spinning speed was 600m / min to obtain the primary fiber. After 24 hours of equilibrium, the stretching heat setting was carried out, and the temperature of the stretching hot box was 270℃, the stretching speed was 300m / min, and the multiple was 3.2. The obtained fiber had a fineness of 5.6 dtex, a single-filament breaking strength of 5.2 cN / dtex, and an initial decomposition temperature in air of 560° C. (TG).

[0044] Example 2

[0045] The PEEK 381G slices produced by Victrex were dried in a vacuum drum dryer at 160°C for 12 hours, the PES E1010 produced by BASF and the TLCPVectraA950 produced by Ticona were dried in a vacuum drum dryer at 140°C for 12 hours, PEEK, PES and TLCP were uniformly mixed in a ratio of 94:3:3 (by weight), added to a screw extruder (SHJ-18 produced by Nanjing Jieente Company) for melt extrusion, and the temperature of each zone of the screw was set at 330-370°C (330°C for the first section, 340°C for the second section, 355°C for the third section, 360°C for the fourth section, and 370°C for the fifth section), and then entered the spinning assembly, the spinning temperature was set to 370°C, a slow cooling ring was configured under the spinneret (36 holes), the temperature of the slow cooling ring was set to 300°C, and the spinning speed was 700m / min to obtain nascent fibers. After 24 hours of equilibration, the fiber was stretched and heat-set at a temperature of 250°C, a stretching speed of 300 m / min, and a multiple of 3.2. The fiber fineness was 4.5 dtex, the single filament breaking strength was 5.4 cN / dtex, and the initial decomposition temperature in air was 558°C (TG).

[0046] Example 3

[0047] The PEEK 381G slices produced by Victrex were dried in a vacuum drum dryer at 160°C for 12 hours, the PES E1010 produced by BASF and the TLCP VectraA950 produced by Ticona were dried in a vacuum drum dryer at 140°C for 12 hours, PEEK, PES and TLCP were uniformly mixed in a ratio of 90:5:5 (by weight), added to a screw extruder (SHJ-18 produced by Nanjing Jieente Company) for melt extrusion, and the temperature of each zone of the screw was set at 320-355°C (320°C for the first section, 330°C for the second section, 335°C for the third section, 340°C for the fourth section, and 355°C for the fifth section), and then entered the spinning assembly, the spinning temperature was set to 360°C, and there was no need to configure a slow cooling ring under the spinneret (36 holes), the spinning speed was 700m / min, and the nascent fiber was obtained. After 24 hours of equilibration, the fiber was stretched and heat-set at a temperature of 250°C, a stretching speed of 300 m / min, and a multiple of 3.5. The fiber fineness was 3.3 dtex, the single filament breaking strength was 6.0 cN / dtex, and the initial decomposition temperature in air was 557°C (TG).

[0048] Example 4

[0049] PEEK 151G (melt index of 28 g / 10 min under 380 ° C and 5 kg test conditions) produced by Victrex was dried in a vacuum drum dryer at 160 ° C for 12 hours. PES E2010 (melt index of 39 g / 10 min under 380 ° C and 5 kg test conditions) produced by BASF and TLCP produced by Ticona were dried in a vacuum drum dryer at 160 ° C for 12 hours. VectraA950 was dried at 140°C in a vacuum drum dryer for 12 hours, and PEEK was mixed with PES and TLCP in a ratio of 90:5:5 (by weight), and then melted and extruded in a screw extruder (SHJ-18 produced by Nanjing Jieente Company). The temperature of each zone of the screw was set at 325-360°C (1st section 325°C, 2nd section 335°C, 3rd section 340°C, 4th section 345°C, 5th section 360°C), and then entered the spinning assembly, and the spinning temperature was set to 360°C. There was no need to configure a cooling ring under the spinneret (36 holes), and the spinning speed was 500m / min to obtain the primary fiber. After 24 hours of equilibrium, the stretching heat setting was carried out, and the temperature of the stretching hot box was 250°C, the stretching speed was 200m / min, and the multiple was 3.0. The obtained fiber had a fineness of 4.5 dtex, a single-filament breaking strength of 5.8 cN / dtex, and an initial decomposition temperature in air of 559° C. (TG).

[0050] Example 5

[0051] PEEK 381G slices produced by Victrex were dried in a vacuum drum dryer at 160°C for 12 hours, PES E1010 produced by BASF and TLCP VectraA950 produced by Ticona were dried in a vacuum drum dryer at 140°C for 12 hours, PEEK, PES and TLCP were uniformly mixed in a ratio of 85:8:7 (by weight), added to a screw extruder (SHJ-18 produced by Nanjing Jieente Company) for melt extrusion, and the temperature of each zone of the screw was set at 320-350°C (320°C for the first section, 330°C for the second section, 335°C for the third section, 340°C for the fourth section, and 350°C for the fifth section), and then entered the spinning assembly, the spinning temperature was set to 355°C, and there was no need to configure a slow cooling ring under the spinneret (36 holes), the spinning speed was 400m / min, and the nascent fiber was obtained. After 24 hours of equilibration, the fiber was stretched and heat-set at a temperature of 250°C, a stretching speed of 200 m / min, and a multiple of 2.5. The fiber fineness was 6.3 dtex, the single filament breaking strength was 3.6 cN / dtex, and the initial decomposition temperature in air was 552°C (TG).

[0052] Example 6

[0053] The PEEK 381G slices produced by Victrex were dried in a vacuum drum dryer at 160°C for 12 hours, the PES E1010 produced by BASF and the TLCP VectraA950 produced by Ticona were dried in a vacuum drum dryer at 140°C for 12 hours, PEEK, PES and TLCP were uniformly mixed in a ratio of 80:10:10 (by weight), added to a screw extruder (SHJ-18 type produced by Nanjing Jieente Company) for melt extrusion, and the temperature of each zone of the screw was set at 320-355°C (320°C for the first section, 330°C for the second section, 335°C for the third section, 340°C for the fourth section, and 355°C for the fifth section), and then entered the spinning assembly, the spinning temperature was set to 350°C, and there was no need to configure a slow cooling ring under the spinneret (36 holes), the spinning speed was 300m / min, and the nascent fiber was obtained. After 24 hours of equilibration, the fiber was stretched and heat-set at a temperature of 250°C, a stretching speed of 200 m / min, and a multiple of 2.4. The fiber fineness was 6.7 dtex, the single filament breaking strength was 3.5 cN / dtex, and the initial decomposition temperature in air was 548°C (TG).

[0054] It can be seen from Examples 1-6 that as the amount of polyethersulfone and thermotropic liquid crystal polyarylate added increases, the fluidity of the melt becomes better and better, thereby reducing the spinning temperature of the system. In addition, the inventors found that when a small amount of polyethersulfone and thermotropic liquid crystal polyarylate is added, the spinning temperature decreases slightly; when the amount added is moderate, the spinning temperature is significantly reduced, and the melt has a high spinnability, which is manifested in a significant increase in the maximum spinning speed; when the amount added is too large, although it can be spun at a lower temperature, the incompatibility between several components increases, which will cause the spinnability of the melt to decrease, which is manifested in a sharp decrease in the maximum spinning speed, and the finished fiber's breaking strength and thermal decomposition temperature decrease. When the amount of polyethersulfone and thermotropic liquid crystal polyarylate added exceeds the scope of the present invention, the spinnability of the system will decrease to the point where the industrial spinning process cannot be completed, and the mechanical properties and heat resistance of the obtained fiber are also significantly reduced, and it cannot be used normally as a polyetheretherketone-based fiber. Therefore, in the present invention, based on the total weight of the polyetheretherketone-based fiber as 100%, the content of polyetheretherketone is preferably 80-98%, the content of polyethersulfone is preferably 1-10%, and the content of thermotropic liquid crystal polyarylate is preferably 1-10%; further preferably, based on the total weight of the polyetheretherketone-based fiber as 100%, the content of polyetheretherketone is 90-94%, the content of polyethersulfone is 3-5%, and the content of thermotropic liquid crystal polyarylate is 3-5%.

[0055] The embodiments of the present invention have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

[0056] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein, on the contrary, the present invention can be extended to all other methods and applications with the same functions.

[0057] All publications, patent applications, patents and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings conventionally understood by those skilled in the art. In the event of a conflict, the definition in this specification shall prevail.

[0058] When this specification uses the prefix "well-known to those skilled in the art", "prior art" or similar terms to introduce materials, substances, methods, steps, devices or components, etc., the objects introduced by the prefix cover those commonly used in the art when this application is filed, but also include those that are not commonly used at present but will become recognized in the art as being suitable for similar purposes.

[0059] The endpoints and any values ​​of the scope disclosed in the present application document are not limited to the precise scope or value, and these scopes or values ​​should be understood to include values ​​close to these scopes or values. For numerical ranges, between the endpoint values ​​of each scope, between the endpoint values ​​of each scope and a separate point value, and between separate point values, one or more new numerical ranges can be combined with each other, and these numerical ranges should be considered as specifically disclosed in this article. Hereinafter, in principle, each technical solution can be combined with each other to obtain a new technical solution, which should also be considered as specifically disclosed in this article.

[0060] In the context of the present specification, any matters or items not mentioned are directly applicable to those known in the art without any changes except those explicitly stated.

[0061] Moreover, any embodiment described in this document may be freely combined with one or more other embodiments described in this document, and the technical solutions or technical ideas formed thereby are deemed to be part of the original disclosure or original record of the present invention, and should not be regarded as new content that has not been disclosed or anticipated in this document, unless a person skilled in the art considers that the combination is obviously unreasonable.

Claims

1. A polyetheretherketone-based fiber comprising polyetheretherketone, polyethersulfone and thermotropic liquid crystal polyarylate.

2. The polyetheretherketone-based fiber according to claim 1, characterized in that: The polyetheretherketone has a melt index of 20-100 g / 10 min, preferably 30-50 g / 10 min, under the test conditions of 380° C. and 5 kg; and / or The polyethersulfone has a melt index of 10-80 g / 10 min, preferably 60-80 g / 10 min, under the test conditions of 380° C. and 5 kg; and / or The melting temperature of the thermotropic liquid crystal polyarylate is above 250°C, preferably above 270°C.

3. The polyetheretherketone-based fiber according to claim 1, characterized in that: Based on the total weight of the polyetheretherketone-based fiber as 100%, the content of polyetheretherketone is 80-98%, the content of polyethersulfone is 1-10%, and the content of thermotropic liquid crystal polyarylate is 1-10%; preferably, based on the total weight of the polyetheretherketone-based fiber as 100%, the content of polyetheretherketone is 90-94%, the content of polyethersulfone is 3-5%, and the content of thermotropic liquid crystal polyarylate is 3-5%.

4. The polyetheretherketone-based fiber according to any one of claims 1 to 3, characterized in that: The polyetheretherketone-based fiber has a fineness of 2.0-10.0 dtex, preferably 3.3-6.7 dtex, and / or a breaking strength of 3.0-7.0 cN / dtex, preferably 3.5-6.0 cN / dtex.

5. The polyetheretherketone-based fiber according to any one of claims 1 to 3, characterized in that: The polyetheretherketone-based fiber is prepared by a preparation method comprising the step of melt-spinning components including polyetheretherketone, polyethersulfone and thermotropic liquid crystal polyarylate.

6. A method for preparing a polyetheretherketone-based fiber as claimed in any one of claims 1 to 5, comprising the step of melt-spinning components comprising polyetheretherketone, polyethersulfone and thermotropic liquid crystal polyarylate.

7. The preparation method according to claim 6, characterized in that: The melting device is a screw extruder; preferably, The screw extruder is at least one of a single-screw extruder and a twin-screw extruder; and / or, The temperature of each zone of the screw of the screw extruder is 320-385°C.

8. The preparation method according to claim 6, characterized in that: The spinning conditions include: a spinning temperature of 350-395°C, preferably 360-385°C; and / or a spinning speed of 300-800m / min, preferably 500-800m / min; and / or a stretching ratio of 2.0-4.0 times, preferably 3.0-3.5 times; and / or a heat setting temperature of 220-270°C, preferably 250-270°C.

9. The preparation method according to claim 6, characterized in that: Before melt spinning, the method further includes drying the polyetheretherketone, polyethersulfone and / or thermotropic liquid crystal polyarylate; preferably, the drying is vacuum drying; more preferably, the vacuum drying temperature is 140-160°C, and / or the vacuum drying time is greater than or equal to 10 hours, preferably 10-12 hours.

10. A polyetheretherketone-based fiber as claimed in any one of claims 1 to 5 or a polyetheretherketone-based fiber obtained by the preparation method as claimed in any one of claims 6 to 9 Application in the field of composite materials, preferably in the field of high temperature resistant composite materials use.