A polyether ether ketone aerogel fiber and a method of making the same
By developing a method for preparing polyetheretherketone (PEEK) aerogel fibers, the problems of weak mechanical properties and complex preparation of aerogel fibers have been solved, achieving high strength, toughness, and spinnability, making it suitable for thermal insulation applications such as textiles and special clothing.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JILIN UNIVERSITY
- Filing Date
- 2024-11-29
- Publication Date
- 2026-05-12
Smart Images
Figure CN119411252B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of aerogel fiber technology, specifically relating to a polyetheretherketone aerogel fiber and its preparation method. Background Technology
[0002] Aerogels are nanoscale porous solid materials formed by replacing the liquid phase in a gel with gas through a sol-gel method and a certain drying process. They have advantages such as low density, high porosity, and large specific surface area, and therefore have wide applications in thermal insulation, catalytic loading, adsorption and filtration.
[0003] Aerogel fibers, in addition to possessing the excellent properties of aerogels, also exhibit fiber flexibility and good mechanical properties. Existing aerogel fibers are mostly aramid aerogel fibers, polyimide aerogel fibers, cellulose aerogel fibers, and various inorganic aerogel fibers. However, the mechanical properties of these aerogel fibers are still relatively weak. Improving the mechanical properties of aerogel fibers requires subsequent processing and modification, and the complex preparation process poses a significant challenge to the production of aerogel fibers.
[0004] For example, patent CN116905120A discloses a method for preparing polyimide composite aerogel fibers. This method involves adding a silica aerogel precursor hydrolysate to a polyamic acid salt solution to prepare a composite spinning solution. After wet spinning, the solution undergoes solvent replacement and freeze-drying to obtain the polyimide aerogel fibers. In this patent, the chemical imidization of the polyamic acid is carried out directly in a coagulation bath, resulting in mild reaction conditions and a controllable reaction process, making it suitable for large-scale production.
[0005] Patent CN115073803B discloses a method for preparing high-toughness aramid aerogel fibers. Instead of using traditional freeze-drying or supercritical drying to process the aerogel fibers, this method prepares aerogel fibers with high porosity, nanoscale pore size, and extremely high fracture toughness by drying under normal pressure. This not only improves production efficiency but also reduces production costs.
[0006] Patent CN117127281A discloses a method for preparing bacterial cellulose / polyurethane composite aerogel fiber. In the above preparation method, the introduction of thermoplastic polyurethane protects the aerogel skeleton to a certain extent and effectively enhances the mechanical strength of the aerogel fiber. The three-dimensional network skeleton and porous structure of the composite aerogel fiber make the aerogel fiber have excellent mechanical properties and good thermal insulation performance.
[0007] Polyaryletherketone (PAGE) materials are widely used in various fields due to their excellent mechanical properties, temperature resistance, and acid and alkali resistance. However, the solvent resistance and high processing temperature of PAGE materials have brought many challenges to the preparation and production of PAGE aerogel fibers. Summary of the Invention
[0008] In view of this, the purpose of the present invention is to provide a polyetheretherketone aerogel fiber and a method for preparing the same, wherein the polyetheretherketone aerogel fiber not only has the advantages of low density and high porosity of aerogel, but also has the flexibility and weavability of fiber.
[0009] The technical solution adopted by the present invention to achieve the above objectives is as follows.
[0010] In a first aspect, the present invention provides a method for preparing polyetheretherketone aerogel fibers, comprising the following steps:
[0011] (1) Dissolve soluble polyether ether ketone-1,3-dithiopentane and polyvinylpyrrolidone in a polar solvent and disperse them evenly to obtain a spinning solution;
[0012] (2) After degassing the spinning solution, the fibers are extruded into a coagulation bath, and collected by winding to obtain polyetheretherketone-1,3-dithiopentane wet gel fibers.
[0013] (3) The polyetheretherketone-1,3-dithiopentane wet gel fiber was placed in a displacement bath for several solvent displacements and then frozen to obtain polyetheretherketone-1,3-dithiopentane fiber.
[0014] (4) The polyetheretherketone-1,3-dithiopentane fiber is dried to obtain polyetheretherketone aerogel fiber.
[0015] Preferably, in step (1), the method for preparing the soluble polyether ether ketone-1,3-dithiopentane is as follows: under an inert atmosphere, crystalline polyether ether ketone is dissolved in a solvent with added additives, and then boron trifluoride ether and 1,2-ethanedithiol are added. After reacting at room temperature for 24-48 hours, the product is discharged into anhydrous ethanol or anhydrous methanol, and after being crushed, washed and dried, soluble polyether ether ketone-1,3-dithiopentane is obtained.
[0016] More preferably, the inert atmosphere is nitrogen;
[0017] More preferably, the crystalline polyetheretherketone has the following structural formula:
[0018]
[0019] In the formula, n is a positive integer, 10≤n≤200;
[0020] More preferably, the concentration of the crystalline polyether ether ketone in the solvent with added additives is 0.05 g / ml to 0.5 g / ml, the molar ratio of the carbonyl content of the crystalline polyether ether ketone to 1,2-ethylenedithiol is 1:2 to 1:5, and the molar ratio of boron trifluoride ethyl ether to 1,2-ethylenedithiol is 1:3 to 1:1.
[0021] More preferably, the additive is trifluoroacetic acid or trifluorobenzoic acid, the solvent is dichloromethane or trichloromethane, and the volume ratio of the additive to the solvent is 1:10-1:5.
[0022] Preferably, in step (1), the polar solvent includes one or more of dimethyl sulfoxide, N-methylpyrrolidone, N,N-dimethylformamide, dimethylacetamide, and tetrahydrofuran, mixed in any proportion.
[0023] Preferably, in step (1), the mass fraction of soluble polyether ether ketone-1,3-dithiopentane in the spinning solution is 5%-30%, and the mass fraction of polyvinylpyrrolidone is 3%-5%.
[0024] Preferably, in step (1), the mixture is dispersed evenly by stirring for 3-12 hours at a speed of 500-1000 rpm.
[0025] More preferably, the stirring time is 6 hours and the stirring speed is 1000 rpm.
[0026] Preferably, in step (2), the extrusion spinning method is wet spinning, and the degassing is vacuum degassing;
[0027] More preferably, the vacuum-degassed spinning solution is injected into a coagulation bath via a syringe and an injection pump to obtain polyetheretherketone-1,3-dithiopentane wet gel fiber, wherein the injection speed is 4-10 ml / h and the syringe needle diameter is 0.41 mm-0.84 mm.
[0028] Preferably, in step (2), the coagulation bath is one or more of the polar solvent, anhydrous ethanol, water, acetone, and methanol selected in step (1) in any proportion.
[0029] More preferably, the coagulation bath is an aqueous solution of ethanol with a volume fraction of 10%-50%.
[0030] Preferably, in step (3), the displacement bath is one or more of water, anhydrous ethanol, and methanol mixed in any proportion;
[0031] More preferably, the displacement bath is an aqueous ethanol solution with a volume fraction of 10%-50%.
[0032] Preferably, in step (3), the solvent replacement time is 24-72 hours, and the replacement bath is replaced every 3-6 hours.
[0033] Preferably, in step (3), the freezing treatment is: placing it in a low temperature freezer at -25℃ to -40℃ for 6-8 hours or in liquid nitrogen at -196℃ for 1-3 hours.
[0034] Preferably, in step (4), the drying is vacuum freeze drying, supercritical drying, or atmospheric pressure drying;
[0035] More preferably, the drying is vacuum freeze drying, with a vacuum degree of 0 Pa, a freeze drying temperature of -50℃ to -70℃, and a drying time of 24-72h.
[0036] Secondly, the present invention provides polyetheretherketone aerogel fibers prepared by the above-mentioned method for preparing polyetheretherketone aerogel fibers.
[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0038] The method for preparing polyetheretherketone aerogel fiber provided by this invention is simple in process and has continuous subsequent processes, and is expected to achieve large-scale production.
[0039] The aerogel fibers prepared by this invention have a typical three-dimensional network structure, low linear density, high strength and good toughness, and good spinnability. Their porous structure provides the possibility for subsequent filling or adsorption of phase change materials in the fields of textiles, special clothing and other thermal insulation. Attached Figure Description
[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0041] Figure 1 These are SEM images (left) and digital images (right) of knotted polyetheretherketone aerogel fibers in Example 1 of this invention;
[0042] Figure 2 The images show the cross-sectional morphology SEM image (left) and a magnified SEM image (right) of the polyetheretherketone aerogel fiber in Example 3 of this invention.
[0043] Figure 3 These are the stress-strain diagram (left) and the optical image (right) of the polyetheretherketone aerogel fiber under a 100g weight during a tensile test in Example 3 of the present invention.
[0044] Figure 4 This is a digital image of a fabric woven from polyetheretherketone aerogel fibers according to Example 1 of the present invention. Detailed Implementation
[0045] To further understand the present invention, preferred embodiments of the present invention are described below. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the claims of the present invention.
[0046] The method for preparing polyetheretherketone aerogel fibers of the present invention includes the following steps:
[0047] (1) Dissolve soluble polyether ether ketone-1,3-dithiopentane and polyvinylpyrrolidone in a polar solvent and stir until homogeneous to obtain a spinning solution;
[0048] (2) After vacuum degassing the spinning solution, the fibers are extruded into a coagulation bath, and collected by winding to obtain polyetheretherketone-1,3-dithiopentane wet gel fibers.
[0049] (3) The polyetheretherketone-1,3-dithiopentane wet gel fiber was placed in a displacement bath for several solvent displacements and then frozen to obtain polyetheretherketone-1,3-dithiopentane fiber.
[0050] (4) The polyetheretherketone-1,3-dithiopentane fiber is dried to obtain polyetheretherketone aerogel fiber.
[0051] Preferably, in step (1), the preparation method of soluble polyether ether ketone-1,3-dithiopentane is as follows: under nitrogen protection, crystalline polyether ether ketone is dissolved in a solvent with added additives, and then boron trifluoride diethyl ether and 1,2-ethanedithiol are added. After reacting at room temperature for 24-48 hours, the product is discharged into anhydrous ethanol or anhydrous methanol, and after pulverizing, washing and drying, soluble polyether ether ketone-1,3-dithiopentane is obtained; wherein, the structural formula of crystalline polyether ether ketone is as follows:
[0052]
[0053] In the formula, n is a positive integer, 10≤n≤200;
[0054] The concentration of crystalline polyether ether ketone in the solvent with added additives is 0.05 g / ml-0.5 g / ml, the molar ratio of carbonyl content of crystalline polyether ether ketone to 1,2-ethylenedithiol is 1:2-1:5, and the molar ratio of boron trifluoride ethyl ether to 1,2-ethylenedithiol is 1:3-1:1; the additive is trifluoroacetic acid or trifluorobenzoic acid, the solvent is dichloromethane or trichloromethane, and the volume ratio of additive to solvent is 1:10-1:5.
[0055] Preferably, in step (1), the polar solvent is one or more of dimethyl sulfoxide, N-methylpyrrolidone, N,N-dimethylformamide, dimethylacetamide, and tetrahydrofuran, mixed in any proportion. However, it should be noted that there are no special restrictions on the choice of polar solvent, as long as it can achieve a dissolving effect.
[0056] Preferably, in step (1), the mass fraction of soluble polyether ether ketone-1,3-dithiopentane in the spinning solution is 5%-30%, and the mass fraction of polyvinylpyrrolidone is 3%-5%.
[0057] Preferably, in step (1), the soluble polyether ether ketone-1,3-dithiopentane is dissolved by stirring at room temperature for 6 hours at a stirring speed of 500-1000 rpm. However, it should be noted that other methods that can achieve the dissolution and uniform dispersion of soluble polyether ether ketone-1,3-dithiopentane are also applicable to this invention, such as ultrasound.
[0058] Preferably, in step (2), the extrusion spinning method is wet spinning, which involves injecting the spinning solution after vacuum degassing into a syringe, which then injects it into the coagulation bath via a micro-injection pump, and adjusting the spinning parameters to achieve wet spinning. It should be noted that vacuum degassing is used to maintain the continuity of the wet spinning process; other degassing methods, such as ultrasound, are also applicable to this invention. The preferred wet spinning parameters are: a spinning solution injection rate of 4-10 ml / h, a syringe needle diameter of 0.41 mm-0.84 mm, and a syringe needle insertion depth of 2 cm below the coagulation bath interface, with the specific parameters selected based on actual conditions.
[0059] Preferably, in step (2), the coagulation bath is one or more of the polar solvent, anhydrous ethanol, water, acetone, and methanol in step (1) mixed in any proportion. More preferably, the coagulation bath is an aqueous solution of ethanol with a volume fraction of 10%-50%.
[0060] Preferably, in step (3), the displacement bath is one or more of water, anhydrous ethanol, and methanol mixed in any proportion; more preferably, the displacement bath is an aqueous solution of ethanol with a volume fraction of 10%-50%. The solvent displacement time is 24-72 hours, and the displacement bath is replaced every 3-6 hours.
[0061] Preferably, the freezing process is one of the following methods:
[0062] The sample is placed in liquid nitrogen for freezing treatment at a temperature of -196°C for 1-3 hours, with a more preferred treatment time of 1 hour.
[0063] The sample is placed in a low-temperature freezer at a temperature of -25°C to -40°C for 6-8 hours; a more preferred freezing time is 6 hours.
[0064] Preferably, in step (4), the treatment method is vacuum freeze-drying, with a vacuum degree of 0 Pa, a freeze-drying temperature of -50℃ to -70℃, and a drying time of 24-72 h. More preferably, the drying time is 48 h. However, it should be noted that there are no special restrictions on the subsequent treatment methods. The main purpose is to remove excess solvent while ensuring the three-dimensional network structure of the aerogel fibers. Supercritical drying, atmospheric pressure drying, etc. can also be selected.
[0065] The polyetheretherketone aerogel fiber of the present invention is prepared by the above method. While possessing the advantages of aerogel such as low density, high porosity and large specific surface area, it also has a certain degree of flexibility, making it very promising for development in the fields of textiles, special clothing and other thermal insulation applications.
[0066] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to embodiments.
[0067] In the following embodiments, various processes and methods not described in detail are conventional methods known in the art. Unless otherwise specified, the materials, reagents, apparatus, instruments, equipment, etc., used in the following embodiments are commercially available. The structural formula of the polyetheretherketone used in the embodiments is as follows:
[0068]
[0069] In the formula, n is a positive integer, 10≤n≤200;
[0070] Example 1
[0071] A method for preparing polyetheretherketone aerogel fibers, comprising the following steps:
[0072] Polyetheretherketone (28.8 g, n = 100) was added in portions to 480 ml of dichloromethane under nitrogen protection and magnetic stirring. After uniform dispersion, 60 ml of trifluoroacetic acid was added. Once the polyetheretherketone was fully dissolved and formed a yellow viscous solution, 1,2-ethanedithiol (10.96 ml, 0.25 mol) and boron trifluoride diethyl ether (31.56 ml, 0.25 mol) were added sequentially. The reaction was carried out at room temperature for 24 h, and then discharged into 3000 ml of anhydrous ethanol. The resulting white solid was mechanically pulverized, washed with anhydrous ethanol, and dried under vacuum at 80 °C for 8 h to obtain white solid polyetheretherketone-1,3-dithiopentane.
[0073] At room temperature, 2g of polyetheretherketone-1,3-dithiopentane and 0.5g of polyvinylpyrrolidone were dissolved in 17.5g of N-methylpyrrolidone and stirred at room temperature for 6h. The resulting solution was then degassed under vacuum for 2h to obtain the spinning solution.
[0074] The spinning solution was extruded into a coagulation bath using a syringe and a micro-injection pump at an injection rate of 8 ml / h. The coagulation bath was an aqueous ethanol solution with an ethanol volume fraction of 50%, resulting in polyetheretherketone-1,3-dithiopentane wet gel fiber. The syringe needle had an inner diameter of 0.84 mm.
[0075] The aforementioned polyetheretherketone-1,3-dithiopentane wet gel fibers were subjected to a 24-hour solvent replacement treatment. Solvent replacement was carried out in an ethanol-water solution (50% ethanol by volume), with the solvent changed every 6 hours for a total of 4 replacements. Then, the fibers were frozen at -25°C for 6 hours to obtain the polyetheretherketone-1,3-dithiopentane fibers.
[0076] Polyetheretherketone (PEEK)-1,3-dithiopentane fibers were freeze-dried to obtain PEEK aerogel fibers. The freeze-drying temperature was -50℃, the vacuum degree was 0 Pa, and the freeze-drying time was 48 h. The obtained PEEK aerogel fibers were tested and found to have a tensile strength of 5.58 MPa, an elongation at break of 21.73%, an elastic modulus of 61.90 MPa, and a linear density of 16.7 tex.
[0077] Example 2
[0078] A method for preparing polyetheretherketone aerogel fibers, comprising the following steps:
[0079] Polyetheretherketone (28.8 g, n = 100) was added in portions to 480 ml of dichloromethane under nitrogen protection and magnetic stirring. After uniform dispersion, 60 ml of trifluoroacetic acid was added. Once the polyetheretherketone was fully dissolved and formed a yellow viscous solution, 1,2-ethanedithiol (10.96 ml, 0.25 mol) and boron trifluoride diethyl ether (31.56 ml, 0.25 mol) were added sequentially. The reaction was carried out at room temperature for 24 h, and then discharged into 3000 ml of anhydrous ethanol. The resulting white solid was mechanically pulverized, washed with anhydrous ethanol, and dried under vacuum at 80 °C for 8 h to obtain white solid polyetheretherketone-1,3-dithiopentane.
[0080] At room temperature, 3g of polyetheretherketone-1,3-dithiopentane and 0.5g of polyvinylpyrrolidone were dissolved in 16.5g of N-methylpyrrolidone and stirred at room temperature for 6 hours. The resulting solution was then degassed under vacuum for 2 hours to obtain the spinning solution.
[0081] The spinning solution was extruded into a coagulation bath using a syringe and a micro-injection pump at an injection rate of 8 ml / h. The coagulation bath was an aqueous ethanol solution with an ethanol volume fraction of 50%, resulting in polyetheretherketone-1,3-dithiopentane wet gel fiber. The syringe needle had an inner diameter of 0.84 mm.
[0082] The aforementioned polyetheretherketone-1,3-dithiopentane wet gel fibers were subjected to a 24-hour solvent replacement treatment. Solvent replacement was carried out in an ethanol-water solution (50% ethanol by volume), with the solvent changed every 6 hours for a total of 4 replacements. Then, the fibers were frozen at -25°C for 6 hours to obtain the polyetheretherketone-1,3-dithiopentane fibers.
[0083] Polyetheretherketone (PEEK)-1,3-dithiopentane fibers were freeze-dried to obtain PEEK aerogel fibers. The freeze-drying temperature was -50℃, the vacuum degree was 0 Pa, and the freeze-drying time was 48 h. The obtained PEEK aerogel fibers were tested and found to have a tensile strength of 5.81 MPa, an elongation at break of 23.54%, an elastic modulus of 69.35 MPa, and a linear density of 17.3 tex.
[0084] Example 3
[0085] A method for preparing polyetheretherketone aerogel fibers, comprising the following steps:
[0086] Polyetheretherketone (28.8 g, n = 100) was added in portions to 480 ml of dichloromethane under nitrogen protection and magnetic stirring. After uniform dispersion, 60 ml of trifluoroacetic acid was added. Once the polyetheretherketone was fully dissolved and formed a yellow viscous solution, 1,2-ethanedithiol (10.96 ml, 0.25 mol) and boron trifluoride diethyl ether (31.56 ml, 0.25 mol) were added sequentially. The reaction was carried out at room temperature for 24 h, and then discharged into 3000 ml of anhydrous ethanol. The resulting white solid was mechanically pulverized, washed with anhydrous ethanol, and dried under vacuum at 80 °C for 8 h to obtain white solid polyetheretherketone-1,3-dithiopentane.
[0087] At room temperature, 4g of polyetheretherketone-1,3-dithiopentane and 0.5g of polyvinylpyrrolidone were dissolved in 15.5g of N-methylpyrrolidone and stirred at room temperature for 6h. The resulting solution was then degassed under vacuum for 2h to obtain the spinning solution.
[0088] The spinning solution was extruded into a coagulation bath using a syringe and a micro-injection pump at an injection rate of 8 ml / h. The coagulation bath was an aqueous ethanol solution with an ethanol volume fraction of 50%, resulting in polyetheretherketone-1,3-dithiopentane wet gel fiber. The syringe needle had an inner diameter of 0.84 mm.
[0089] The aforementioned polyetheretherketone-1,3-dithiopentane wet gel fibers were subjected to a 24-hour solvent replacement treatment. Solvent replacement was carried out in an ethanol-water solution (50% ethanol by volume), with the solvent changed every 6 hours for a total of 4 replacements. Then, the fibers were frozen at -25°C for 6 hours to obtain the polyetheretherketone-1,3-dithiopentane fibers.
[0090] Polyetheretherketone (PEEK)-1,3-dithiopentane fibers were freeze-dried to obtain PEEK aerogel fibers. The freeze-drying temperature was -50℃, the vacuum degree was 0 Pa, and the freeze-drying time was 48 h. The obtained PEEK aerogel fibers were tested and found to have a tensile strength of 6.15 MPa, an elongation at break of 25.81%, an elastic modulus of 76.11 MPa, and a linear density of 18.6 tex.
[0091] Example 4
[0092] A method for preparing polyetheretherketone aerogel fibers, comprising the following steps:
[0093] Polyetheretherketone (28.8 g, n = 100) was added in portions to 480 ml of dichloromethane under nitrogen protection and magnetic stirring. After uniform dispersion, 60 ml of trifluoroacetic acid was added. Once the polyetheretherketone was fully dissolved and formed a yellow viscous solution, 1,2-ethanedithiol (10.96 ml, 0.25 mol) and boron trifluoride diethyl ether (31.56 ml, 0.25 mol) were added sequentially. The reaction was carried out at room temperature for 24 h, and then discharged into 3000 ml of anhydrous ethanol. The resulting white solid was mechanically pulverized, washed with anhydrous ethanol, and dried under vacuum at 80 °C for 8 h to obtain white solid polyetheretherketone-1,3-dithiopentane.
[0094] At room temperature, 4g of polyetheretherketone-1,3-dithiopentane and 0.5g of polyvinylpyrrolidone were dissolved in 15.5g of N-methylpyrrolidone and stirred at room temperature for 6h. The resulting solution was then degassed under vacuum for 2h to obtain the spinning solution.
[0095] The spinning solution was extruded into a coagulation bath using a syringe and a micro-injection pump at an injection rate of 8 ml / h. The coagulation bath was an aqueous ethanol solution with an ethanol volume fraction of 50%, resulting in polyetheretherketone-1,3-dithiopentane wet gel fiber. The syringe needle had an inner diameter of 0.62 mm.
[0096] The aforementioned polyetheretherketone-1,3-dithiopentane wet gel fibers were subjected to a 24-hour solvent replacement treatment. Solvent replacement was carried out in an ethanol-water solution (50% ethanol by volume), with the solvent changed every 6 hours for a total of 4 replacements. Then, the fibers were frozen at -25°C for 6 hours to obtain the polyetheretherketone-1,3-dithiopentane fibers.
[0097] Polyetheretherketone (PEEK)-1,3-dithiopentane fibers were freeze-dried to obtain PEEK aerogel fibers. The freeze-drying temperature was -50℃, the vacuum degree was 0 Pa, and the freeze-drying time was 48 h. The obtained PEEK aerogel fibers were tested and found to have a tensile strength of 6.02 MPa, an elongation at break of 24.98%, an elastic modulus of 71.25 MPa, and a linear density of 17.9 tex.
[0098] Example 5
[0099] A method for preparing polyetheretherketone aerogel fibers, comprising the following steps:
[0100] Polyetheretherketone (28.8 g, n = 100) was added in portions to 480 ml of dichloromethane under nitrogen protection and magnetic stirring. After uniform dispersion, 60 ml of trifluoroacetic acid was added. Once the polyetheretherketone was fully dissolved and formed a yellow viscous solution, 1,2-ethanedithiol (10.96 ml, 0.25 mol) and boron trifluoride diethyl ether (31.56 ml, 0.25 mol) were added sequentially. The reaction was carried out at room temperature for 24 h, and then discharged into 3000 ml of anhydrous ethanol. The resulting white solid was mechanically pulverized, washed with anhydrous ethanol, and dried under vacuum at 80 °C for 8 h to obtain white solid polyetheretherketone-1,3-dithiopentane.
[0101] At room temperature, 4g of polyetheretherketone-1,3-dithiopentane and 0.5g of polyvinylpyrrolidone were dissolved in 15.5g of N-methylpyrrolidone and stirred at room temperature for 6h. The resulting solution was then degassed under vacuum for 2h to obtain the spinning solution.
[0102] The spinning solution was extruded into a coagulation bath using a syringe and a micro-injection pump at an injection rate of 8 ml / h. The coagulation bath was an aqueous ethanol solution with an ethanol volume fraction of 50%, resulting in polyetheretherketone-1,3-dithiopentane wet gel fiber. The syringe needle had an inner diameter of 0.51 mm.
[0103] The aforementioned polyetheretherketone-1,3-dithiopentane wet gel fibers were subjected to a 24-hour solvent replacement treatment. Solvent replacement was carried out in an ethanol-water solution (50% ethanol by volume), with the solvent changed every 6 hours for a total of 4 replacements. Then, the fibers were frozen at -25°C for 6 hours to obtain the polyetheretherketone-1,3-dithiopentane fibers.
[0104] Polyetheretherketone (PEEK)-1,3-dithiopentane fibers were freeze-dried to obtain PEEK aerogel fibers. The freeze-drying temperature was -50℃, the vacuum degree was 0 Pa, and the freeze-drying time was 48 h. The obtained PEEK aerogel fibers were tested and found to have a tensile strength of 5.75 MPa, an elongation at break of 22.99%, an elastic modulus of 68.76 MPa, and a linear density of 16.8 tex.
[0105] Example 6
[0106] A method for preparing polyetheretherketone aerogel fibers, comprising the following steps:
[0107] Polyetheretherketone (28.8 g, n = 100) was added in portions to 480 ml of dichloromethane under nitrogen protection and magnetic stirring. After uniform dispersion, 60 ml of trifluoroacetic acid was added. Once the polyetheretherketone was fully dissolved and formed a yellow viscous solution, 1,2-ethanedithiol (10.96 ml, 0.25 mol) and boron trifluoride diethyl ether (31.56 ml, 0.25 mol) were added sequentially. The reaction was carried out at room temperature for 24 h, and then discharged into 3000 ml of anhydrous ethanol. The resulting white solid was mechanically pulverized, washed with anhydrous ethanol, and dried under vacuum at 80 °C for 8 h to obtain white solid polyetheretherketone-1,3-dithiopentane.
[0108] At room temperature, 4g of polyetheretherketone-1,3-dithiopentane and 0.5g of polyvinylpyrrolidone were dissolved in 15.5g of N-methylpyrrolidone and stirred at room temperature for 6h. The resulting solution was then degassed under vacuum for 2h to obtain the spinning solution.
[0109] The spinning solution was extruded into a coagulation bath using a syringe and a micro-injection pump at an injection rate of 8 ml / h. The coagulation bath was an aqueous ethanol solution with an ethanol volume fraction of 50%, resulting in polyetheretherketone-1,3-dithiopentane wet gel fiber. The syringe needle had an inner diameter of 0.41 mm.
[0110] The aforementioned polyetheretherketone-1,3-dithiopentane wet gel fibers were subjected to a 24-hour solvent replacement treatment. Solvent replacement was carried out in an ethanol-water solution (50% ethanol by volume), with the solvent changed every 6 hours for a total of 4 replacements. Then, the fibers were frozen at -25°C for 6 hours to obtain the polyetheretherketone-1,3-dithiopentane fibers.
[0111] Polyetheretherketone (PEEK)-1,3-dithiopentane fibers were freeze-dried to obtain PEEK aerogel fibers. The freeze-drying temperature was -50℃, the vacuum degree was 0 Pa, and the freeze-drying time was 48 h. The obtained PEEK aerogel fibers were tested and found to have a tensile strength of 5.49 MPa, an elongation at break of 21.65%, an elastic modulus of 60.77 MPa, and a linear density of 16.3 tex.
[0112] Electron microscopy was performed on the polyetheretherketone aerogel fibers prepared in Examples 1-3, and the results are as follows: Figure 1As shown in the middle left image, it can be clearly observed that the morphology of the prepared aerogel fibers did not change significantly after knotting, with no breakage, and the shape was regular and intact. Furthermore, optical image observation of the prepared aerogel fibers shows... Figure 1 As shown in the right figure, no damage was observed on the surface of the aerogel fiber, indicating that the polyether ether ketone aerogel fiber prepared by the method of the present invention has good flexibility.
[0113] Electron microscopy was performed on the fracture cross-section of the polyetheretherketone aerogel fiber prepared in Example 3, and the structure is as follows: Figure 2 As shown, from Figure 2 The left image shows that the prepared polyetheretherketone aerogel fibers have a porous structure, and large finger-like pores can be observed. This is caused by the excessively rapid phase exchange rate between the aerogel fiber spinning solution and the coagulation bath. However, the surface of the formed finger-like pores also exhibits a large number of porous structures, with pore diameters approximately 1 μm. Figure 2 As can be observed in the right figure, there are a large number of regular porous structures inside the prepared polyether ether ketone aerogel fiber, with a pore diameter of about 1 μm. This three-dimensional porous structure inside gives the polyether ether ketone aerogel fiber advantages such as low density and high porosity, and also provides conditions for the subsequent adsorption of phase change materials by the polyether ether ketone aerogel fiber to achieve thermal management.
[0114] Stress-strain testing was performed on the polyetheretherketone aerogel fibers prepared in Example 3, and the test structure is as follows: Figure 3 As shown in the left figure, from Figure 3 The left image shows that the prepared polyetheretherketone aerogel fibers possess certain mechanical properties. Figure 3 The optical image on the right shows that the prepared polyetheretherketone aerogel fiber can withstand a weight of 100g, which also indicates that the aerogel fiber has a certain mechanical strength.
[0115] The polyetheretherketone aerogel fibers prepared in Example 1 were woven, and optical images were observed on them, such as... Figure 4 As shown, from Figure 4 It can be observed that the prepared polyetheretherketone aerogel fibers can be woven into fabrics, and the fiber structure remains intact and regular. No damage was found in the fibers, indicating that the prepared aerogel fibers have a certain degree of weavability.
[0116] Obviously, the above embodiments are merely illustrative examples for clarity and are not intended to limit the embodiments. Those skilled in the art can make various variations or modifications based on the above description. It is neither necessary nor possible to exhaustively list all embodiments here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.
Claims
1. A method for preparing polyetheretherketone aerogel fibers, characterized in that, Includes the following steps: (1) Dissolve soluble polyether ether ketone-1,3-dithiopentane and polyvinylpyrrolidone in a polar solvent and disperse them evenly to obtain a spinning solution; The method for preparing the soluble polyether ether ketone-1,3-dithiopentane is as follows: under an inert atmosphere, crystalline polyether ether ketone is dissolved in a solvent with added additives, and then boron trifluoride diethyl ether and 1,2-ethanedithiol are added. After reacting at room temperature for 24-48 hours, the product is discharged into anhydrous ethanol or anhydrous methanol, and after pulverizing, washing and drying, soluble polyether ether ketone-1,3-dithiopentane is obtained. The structural formula of the crystalline polyetheretherketone is as follows: In the formula, n is a positive integer, 10≤n≤200; The concentration of the crystalline polyether ether ketone in the solvent with added additives is 0.05 g / ml-0.5 g / ml, the molar ratio of the carbonyl content of the crystalline polyether ether ketone to 1,2-ethylenedithiol is 1:2-1:5, and the molar ratio of boron trifluoride ethyl ether to 1,2-ethylenedithiol is 1:3-1:
1. The auxiliary agent is trifluoroacetic acid or trifluorobenzoic acid, the solvent is dichloromethane or trichloromethane, and the volume ratio of auxiliary agent to solvent is 1:10-1:5; (2) After degassing the spinning solution, the fibers are extruded into a coagulation bath, and collected by winding to obtain polyetheretherketone-1,3-dithiopentane wet gel fibers. (3) The polyetheretherketone-1,3-dithiopentane wet gel fiber was placed in a displacement bath for several solvent displacements and then frozen to obtain polyetheretherketone-1,3-dithiopentane fiber. (4) The polyetheretherketone-1,3-dithiopentane fiber is dried to obtain polyetheretherketone aerogel fiber.
2. The method for preparing polyetheretherketone aerogel fiber according to claim 1, characterized in that, In step (1), the inert atmosphere is nitrogen.
3. The method for preparing polyetheretherketone aerogel fiber according to claim 1, characterized in that, In step (1), The polar solvent includes one or more of dimethyl sulfoxide, N-methylpyrrolidone, N,N-dimethylformamide, dimethylacetamide, and tetrahydrofuran, mixed in any proportion; In the spinning solution, the mass fraction of soluble polyetheretherketone-1,3-dithiopentane is 5%-30%, and the mass fraction of polyvinylpyrrolidone is 3%-5%. The mixture is dispersed evenly by stirring for 6 hours at a speed of 500-1000 rpm.
4. The method for preparing polyetheretherketone aerogel fiber according to claim 1, characterized in that, In step (2), The extrusion spinning method is wet spinning; The coagulation bath is one or more of the polar solvent, anhydrous ethanol, water, acetone and methanol in step (1) mixed in any proportion; The degassing is vacuum degassing.
5. The method for preparing polyetheretherketone aerogel fiber according to claim 4, characterized in that, The vacuum-degassed spinning solution is injected into a coagulation bath via a syringe and injection pump to obtain polyetheretherketone-1,3-dithiopentane wet gel fiber. The injection speed is 4-10 ml / h, and the syringe needle diameter is 0.41 mm-0.84 mm. The coagulation bath is an aqueous solution of ethanol with a volume fraction of 10%-50%.
6. The method for preparing polyetheretherketone aerogel fiber according to claim 1, characterized in that, In step (3), The displacement bath is one or more of water, anhydrous ethanol, and methanol in any proportion; The solvent replacement time is 24-72 hours, and the replacement bath is changed every 3-6 hours. The freezing treatment is as follows: placing the container in a low-temperature freezer at -25℃ to -40℃ for 6-8 hours or in liquid nitrogen at -196℃ for 1-3 hours.
7. The method for preparing polyetheretherketone aerogel fiber according to claim 6, characterized in that, The displacement bath is an aqueous solution of ethanol with a volume fraction of 10%-50%.
8. The method for preparing polyetheretherketone aerogel fiber according to claim 1, characterized in that, In step (4), the drying is vacuum freeze drying, supercritical drying or atmospheric pressure drying.
9. The method for preparing polyetheretherketone aerogel fiber according to claim 8, characterized in that, The drying process is vacuum freeze drying, with a vacuum degree of 0 Pa, a freeze drying temperature of -50℃ to -70℃, and a drying time of 24-72 hours.
10. Polyetheretherketone aerogel fibers prepared by the method for preparing polyetheretherketone aerogel fibers according to any one of claims 1-9.