A radiation cooling and heat conducting polyetheretherketone composite material and its preparation method and application

Abstract

The present invention provides a polyetheretherketone (PEEK) composite material with radiative cooling and thermal conductivity, as well as a preparation method and application thereof. The preparation method of the composite material comprises the following specific steps: S1, calcining boron nitride at high temperature and cooling it in the furnace to obtain hydroxyl-modified boron nitride; S2, dispersing aramid staple fibers in a poor solvent and shearing them at high speed to form microspheres, i.e., aramid fiber balls; S3, uniformly mixing the aramid fiber balls in S2 with polyetheretherketone (PEEK) powder, then adding the hydroxyl-modified boron nitride in S1, and continuing to mix uniformly to obtain a composite material dispersion; S4, melt-hot pressing the composite material dispersion in S3 to obtain the target PEEK composite material. The material preparation method of the present invention is simple, and the prepared PEEK composite material exhibits excellent radiative cooling performance, thermal conductivity, and thermal stability, and has broad application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and in particular to a radiation cooling and heat conducting polyetheretherketone composite material and a preparation method and application thereof. Background Art

[0002] As global warming and the greenhouse effect continue to intensify, people are increasingly using cooling equipment such as air conditioners and fans, resulting in a large amount of energy consumption. Passive daytime radiant cooling technology with zero energy consumption has attracted extensive research.

[0003] Patent CN118421115A discloses a passive radiative cooling coating that not only has vivid colors but also forms a photonic structure through dense packing, which facilitates passive radiative cooling of the material. Patent CN118727269A discloses a radiative cooling composite film with excellent mechanical, optical, hydrophobic, and thermal stability properties. However, current research on radiative cooling composite materials still faces many challenges, such as poor scalability, insufficient material selectivity, limited application scenarios, and difficulty in using them under harsh conditions.

[0004] As a specialty engineering plastic, polyetheretherketone (PEEK) possesses excellent structural stability and infrared emission capabilities, showing great potential for application in radiative cooling. However, research on PEEK-based composites for passive daytime radiative cooling is rare. Furthermore, research has shown that high thermal conductivity facilitates heat transfer from indoor areas to the outdoors, and therefore materials with high thermal conductivity are generally beneficial for passive cooling. Therefore, there is a need to improve the thermal conductivity of composite materials to enhance their potential and utility. Summary of the Invention

[0005] In view of this, the present invention proposes a radiation cooling and thermal conductive polyetheretherketone composite material and its preparation method and application to solve the above technical problems. The obtained polyetheretherketone composite material exhibits excellent radiation cooling performance and excellent thermal conductivity.

[0006] The technical solution of the present invention is achieved as follows:

[0007] A method for preparing a radiative cooling and heat-conducting polyetheretherketone composite material, comprising the following steps:

[0008] S1, calcining boron nitride at high temperature and cooling it in the furnace to obtain hydroxyl-modified boron nitride, named HO-BN;

[0009] S2, dispersing aramid staple fibers (ANF) in a poor solvent and shearing at high speed to form microspheres, i.e., aramid fiber balls;

[0010] S3, mixing the aramid fiber balls of S2 and polyetheretherketone (PEEK) powder evenly, then adding the hydroxyl-modified boron nitride (HO-BN) of S1, and continuing to mix evenly to obtain a composite material dispersion;

[0011] S4. Melt and hot-press the composite material dispersion of S3 to obtain the target polyetheretherketone composite material, namely HO-BN&ANF / PEEK.

[0012] Furthermore, in step S1, the high-temperature calcination is carried out in an atmosphere of air, at a temperature of 1000-1200° C., for a time of 4-10 hours.

[0013] Furthermore, in step S2, the poor solvent is any one of water, ethanol or acetone.

[0014] Furthermore, in step S2, the solid-liquid ratio of the aramid staple fiber to the poor solvent is 1:250-350 g / mL.

[0015] Furthermore, in step S2, the high-speed shearing is performed at a rotation speed of 500-1000 rpm for 10-12 hours.

[0016] Furthermore, in step S3, the mass ratio of the aramid fiber balls to the polyetheretherketone powder is 1-2:1-2.

[0017] Furthermore, in step S3, the hydroxyl-modified boron nitride accounts for 5%-50% of the total mass of the aramid fiber balls, polyetheretherketone powder and hydroxyl-modified boron nitride.

[0018] Furthermore, in step S4, the melt hot pressing is performed at 3-5 MPa and 345-380° C. for pre-pressing for 10-15 minutes, and then the pressure is increased to 10-30 MPa and maintained for 8-20 minutes.

[0019] A radiation cooling and heat conducting polyetheretherketone composite material is prepared by the above-mentioned preparation method.

[0020] A radiative cooling, thermally conductive polyetheretherketone composite material with applications in military aviation, construction, energy, and electronic packaging.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The material preparation method of the present invention is simple, and the prepared polyetheretherketone composite material exhibits excellent radiation cooling performance, thermal conductivity and thermal stability.

[0023] 2. The micro-nanostructure of the aramid fiber balls of this invention, combined with the effective solar scattering of polyetheretherketone (PEEK), synergistically enhances the reflective capability of the composite material. The hydroxyl-modified boron nitride further improves the composite material's spectral selectivity and enhances its interfacial compatibility with PEEK. It also forms hydrogen bonds with the amide bonds in the aramid fiber balls, strengthening interactions between the materials, reducing phonon scattering, lowering interfacial thermal resistance, and facilitating heat transfer. Furthermore, the large volume of the aramid fiber balls allows the hydroxyl-modified boron nitride to form an insulating structure, creating a comprehensive thermal pathway and effectively improving the thermal conductivity of the composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Infrared images of boron nitride and hydroxyl-modified boron nitride.

[0025] Figure 2 The thermogravimetric curves of the HO-BN&ANF / PEEK composite materials of Example 1 and Examples 4-8 are shown.

[0026] Figure 3 The UV-visible reflectance spectrum images of the composite materials of Example 1 and Comparative Examples 1-2.

[0027] Figure 4 The infrared emissivity spectrum images of the composite materials of Example 1 and Comparative Examples 1-2 are shown.

[0028] Figure 5 This is a test chart of the cooling ability of the composite material of Example 1. DETAILED DESCRIPTION

[0029] In order to better understand the technical content of the present invention, specific examples are provided below to further illustrate the present invention.

[0030] Unless otherwise specified, the experimental methods used in the examples of the present invention are all conventional methods.

[0031] Unless otherwise specified, the materials, reagents, etc. used in the examples of the present invention can be obtained from commercial sources.

[0032] The size of the aramid staple fiber of the present invention is 1-2 mm; the heating rate of the S1 calcination and the heating rate of the S4 melt hot pressing of the present invention are not specifically limited, and any rate familiar to those skilled in the art can be used; the mixing stirring rate in S3 is not specifically limited, and any stirring frequency familiar to those skilled in the art can be used; the poor solvent of the present invention is any one of water, ethanol or acetone.

[0033] Example 1

[0034] The preparation method of the radiation cooling and heat conducting polyetheretherketone composite material of this embodiment comprises the following specific steps:

[0035] S1. Place 10 g of boron nitride in a tube furnace under air atmosphere and perform high-temperature calcination. Specifically, the temperature is raised to 1100°C at a heating rate of 10°C / min, kept at this temperature for 6 hours, and then cooled to room temperature with the furnace to obtain hydroxyl-modified boron nitride, named HO-BN.

[0036] S2, 10 g of aramid staple fiber (ANF) was dispersed in 3000 mL of acetone, sheared at 750 rpm for 11 h to form microspheres, washed, and vacuum-dried at 80 °C for 12 h to obtain aramid fiber balls;

[0037] S3. Weigh 5 g of aramid fiber balls and 5 g of polyetheretherketone (PEEK) powder into a three-dimensional dynamic mixer and mix at 300 rpm for 2 h. Then, add 10 g of hydroxyl-modified boron nitride (HO-BN) and continue mixing for 1 h to obtain a composite material dispersion with a HO-BN filling content of 50 wt%;

[0038] S4. Melt and hot-press the composite material dispersion, specifically: spread the composite material dispersion in a mold with an inner diameter of 5×5 cm, pre-press for 10 minutes in a molding machine at 5 MPa and 360°C, keep the temperature unchanged, pressurize to 20 MPa, apply pressure for 15 minutes, remove the pressure, and cool to room temperature to obtain the target polyetheretherketone composite material, i.e., 50 wt% HO-BN&ANF / PEEK.

[0039] Example 2

[0040] The preparation method of the radiation cooling and heat conducting polyetheretherketone composite material of this embodiment comprises the following specific steps:

[0041] S1. Place 10 g of boron nitride in a tube furnace under air atmosphere and perform high-temperature calcination. Specifically, the temperature is raised to 1000°C at a heating rate of 10°C / min, kept at this temperature for 4 hours, and then cooled to room temperature in the furnace to obtain hydroxyl-modified boron nitride, named HO-BN.

[0042] S2, 10 g of aramid staple fiber (ANF) was dispersed in 2500 mL of acetone, sheared at 500 rpm for 10 h to form microspheres, washed, and vacuum-dried at 80 °C for 12 h to obtain aramid fiber balls;

[0043] S3. Weigh 5 g of aramid fiber balls and 10 g of polyetheretherketone (PEEK) powder into a three-dimensional dynamic mixer and mix at 300 rpm for 2 h. Then, add 15 g of hydroxyl-modified boron nitride (HO-BN) and continue mixing for 1 h to obtain a composite material dispersion with a HO-BN filling content of 50 wt%;

[0044] S4. Melt hot pressing the composite material dispersion, specifically: spread the composite material dispersion in a mold with an inner diameter of 5×5 cm, pre-press for 15 minutes in a molding machine at 3 MPa and 345°C, keep the temperature unchanged, pressurize to 10 MPa, apply pressure for 8 minutes, remove the pressure, and cool to room temperature to obtain the target polyetheretherketone composite material, i.e., 50 wt% HO-BN&ANF / PEEK.

[0045] Example 3

[0046] The preparation method of the radiation cooling and heat conducting polyetheretherketone composite material of this embodiment comprises the following specific steps:

[0047] S1. Place 10 g of boron nitride in a tube furnace under air atmosphere and perform high-temperature calcination. Specifically, the temperature is raised to 1200°C at a heating rate of 10°C / min, kept at this temperature for 10 h, and then cooled to room temperature with the furnace to obtain hydroxyl-modified boron nitride, named HO-BN.

[0048] S2, 10 g of aramid staple fiber (ANF) was dispersed in 3500 mL of acetone, sheared at 1000 rpm for 12 h to form microspheres, washed, and vacuum-dried at 80 °C for 12 h to obtain aramid fiber balls;

[0049] S3. Weigh 10 g of aramid fiber balls and 5 g of polyetheretherketone (PEEK) powder into a three-dimensional dynamic mixer and mix at 300 rpm for 2 h. Then, add 10 g of hydroxyl-modified boron nitride (HO-BN) and continue mixing for 1 h to obtain a composite material dispersion with a HO-BN filling content of 50 wt%;

[0050] S4. Melt and hot-press the composite material dispersion, specifically: spread the composite material dispersion in a mold with an inner diameter of 5×5 cm, pre-press for 15 minutes in a molding machine at 5 MPa and 380°C, keep the temperature unchanged, pressurize to 30 MPa, apply pressure for 20 minutes, remove the pressure, and cool to room temperature to obtain the target polyetheretherketone composite material, i.e., 50 wt% HO-BN&ANF / PEEK.

[0051] Example 4

[0052] On the basis of Example 1, the amount of hydroxyl-modified boron nitride added in step S3 was adjusted to 6.67 g, and finally 40 wt % HO-BN&ANF / PEEK was obtained.

[0053] Example 5

[0054] On the basis of Example 1, the amount of hydroxyl-modified boron nitride added in step S3 was adjusted to 4.29 g, and finally 30 wt % HO-BN&ANF / PEEK was obtained.

[0055] Example 6

[0056] On the basis of Example 1, the amount of hydroxyl-modified boron nitride added in step S3 was adjusted to 2.5 g, and finally 20 wt % HO-BN&ANF / PEEK was obtained.

[0057] Example 7

[0058] On the basis of Example 1, the amount of hydroxyl-modified boron nitride added in step S3 was adjusted to 1.1 g, and finally 10 wt % HO-BN&ANF / PEEK was obtained.

[0059] Example 8

[0060] On the basis of Example 1, the amount of hydroxyl-modified boron nitride added in step S3 was adjusted to 0.53 g, and finally 5 wt % HO-BN&ANF / PEEK was obtained.

[0061] Test Example 1

[0062] The thermal conductivity of 50 wt% HO-BN&ANF / PEEK prepared in Examples 1-3 and 5 wt% HO-BN&ANF / PEEK and 40 wt% HO-BN&ANF / PEEK prepared in Examples 4-8 was tested using a thermal conductivity tester (flash method LFA467, Germany). The results are shown in Table 1.

[0063] Table 1

[0064]

[0065] It can be seen from Table 1 that the HO-BN & ANF / PEEK composite materials prepared by the preparation method of the present invention have excellent thermal conductivity, and the greater the HO-BN filling amount, the better the thermal conductivity.

[0066] Among them, see Figure 1 The infrared image shows that 814cm -1 and 1369cm -1 The infrared characteristic peak of BN bond is 3343cm -1 The broad peak appearing at is the OH absorption peak, indicating that boron nitride has been successfully modified.

[0067] Figure 2 The thermogravimetric curves of the HO-BN&ANF / PEEK composite materials of Example 1 and Examples 4-8 are shown in FIG. Figure 2 It can be seen that the temperature when the composite material loses 5% of its weight is higher than 575° C., indicating that the HO-BN&ANF / PEEK composite materials prepared in Example 1 and Examples 4-8 have good thermal stability.

[0068] Comparative Example 1

[0069] The difference from Example 1 is that the hydroxyl-modified boron nitride is replaced by boron nitride, and the rest is the same as Example 1.

[0070] That is, the preparation method of the radiation cooling and heat conducting polyetheretherketone composite material of this comparative example comprises the following specific steps:

[0071] S1. 10 g of aramid staple fiber (ANF) was dispersed in 3000 mL of acetone, sheared at 750 rpm for 11 h to form microspheres, washed, and vacuum-dried at 80 °C for 12 h to obtain aramid fiber balls.

[0072] S2. Weigh 5 g of aramid fiber balls and 5 g of polyetheretherketone (PEEK) powder into a three-dimensional dynamic mixer and mix at 300 rpm for 2 h. Then, add 10 g of boron nitride (BN) and continue mixing for 1 h to obtain a composite material dispersion with a BN filling content of 50 wt%;

[0073] S4. Melt and hot-press the composite material dispersion, specifically: spread the composite material dispersion in a mold with an inner diameter of 5×5 cm, pre-press for 10 minutes in a molding machine at 5 MPa and 360°C, keep the temperature unchanged, pressurize to 20 MPa, apply pressure for 15 minutes, remove the pressure, and cool to room temperature to obtain a composite material, i.e., 50 wt% BN&ANF / PEEK.

[0074] Comparative Example 2

[0075] The difference from Example 1 is that the aramid fiber balls are missing, and the rest is the same as Example 1.

[0076] That is, the preparation method of the radiation cooling and heat conducting polyetheretherketone composite material of this comparative example comprises the following specific steps:

[0077] S1. Place 10 g of boron nitride in a tube furnace under air atmosphere and perform high-temperature calcination. Specifically, the temperature is raised to 1100°C at a heating rate of 10°C / min, kept at this temperature for 6 hours, and then cooled to room temperature with the furnace to obtain hydroxyl-modified boron nitride, named HO-BN.

[0078] S2. Weigh 5 g of polyetheretherketone (PEEK) powder and 10 g of hydroxyl-modified boron nitride (HO-BN) into a three-dimensional dynamic mixer and mix at 300 rpm for 2 h to obtain a composite material dispersion with a HO-BN filling amount of 50 wt%;

[0079] S4. Melt hot pressing the composite material dispersion, specifically: spread the composite material dispersion in a mold with an inner diameter of 5×5 cm, pre-press for 10 minutes in a molding machine at 5 MPa and 360°C, keep the temperature unchanged, pressurize to 20 MPa, apply pressure for 15 minutes, remove the pressure, and cool to room temperature to obtain a composite material, i.e., 50 wt% HO-BN / PEEK.

[0080] Test Example 2

[0081] The composite materials of Example 1 and Comparative Examples 1 and 2 were tested for sunlight reflection ability, infrared radiation ability and radiation cooling performance. In addition, the thermal conductivity of Comparative Examples 1 and 2 was tested using the method in Test Example 1. The results are as follows: Figure 3-5 and as shown in Table 2.

[0082] Table 2

[0083]

[0084] As can be seen from Table 2, comparative example 1 uses boron nitride, and the thermal conductivity of its composite material is reduced. This shows that the hydroxyl-modified boron nitride used in the present invention can produce hydrogen bonds with the amide bonds in the aramid fiber balls, strengthen the interaction between materials, reduce phonon scattering, reduce interfacial thermal resistance, promote heat flow transmission, and improve thermal conductivity. Comparative example 2 lacks aramid fiber balls, and the thermal conductivity of its composite material is reduced, indicating that the large volume of aramid fiber balls allows the hydroxyl-modified boron nitride to form an isolation structure, construct a complete heat conduction path, and improve the thermal conductivity of the composite material. This shows that the hydroxyl-modified boron nitride and aramid fiber balls synergistically enhance the thermal conductivity of the composite material.

[0085] In addition, from Figure 3 The UV-visible reflectivity spectra of Example 1 show that the average reflectivity is greater than that of Comparative Examples 1 and 2. Compared with Comparative Example 1, the hydroxyl-modified boron nitride in Example 1 enhances the solar reflectivity of the composite material. Compared with Comparative Example 2, the micro-nanostructure of the aramid fiber balls in Example 1 synergistically enhances the solar reflectivity of the composite material.

[0086] from Figure 4 It can be seen from the infrared emissivity spectrum that in the two atmospheric windows of 3-5μm and 8-13μm, the infrared radiation capacity of Example 1 of the present invention is higher than that of Comparative Example 1 and Comparative Example 2.

[0087] from Figure 5 It can be seen from the cooling capacity test that under outdoor environmental conditions, the composite material of Example 1 of the present invention can achieve an ambient temperature drop of up to 10.85°C, indicating that it has good radiation cooling performance.

[0088] However, the radiation cooling performance of Comparative Examples 1 and 2 decreased.

[0089] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a radiation cooling and heat conducting polyetheretherketone composite material, characterized in that: The specific steps include: S1, calcining boron nitride at a high temperature and cooling it in the furnace to obtain hydroxyl-modified boron nitride; S2, dispersing the aramid staple fibers in a poor solvent and shearing them at high speed to form microspheres, i.e., aramid fiber balls; S3, mixing the aramid fiber balls of S2 and the polyetheretherketone powder evenly, then adding the hydroxyl-modified boron nitride of S1, and continuing to mix evenly to obtain a composite material dispersion; S4. Melt and hot-press the composite material dispersion of S3 to obtain the target polyetheretherketone composite material.

2. The method for preparing a radiation cooling and heat conducting polyetheretherketone composite material according to claim 1, characterized in that: In step S1, the high-temperature calcination is carried out in an atmosphere of air, at a temperature of 1000-1200° C., for a time of 4-10 hours.

3. The method for preparing a radiative cooling and thermally conductive polyetheretherketone composite material according to claim 1, characterized in that: In step S2, the poor solvent is any one of water, ethanol or acetone.

4. The method for preparing a radiative cooling and heat-conducting polyetheretherketone composite material according to claim 1, characterized in that: In step S2, the solid-to-liquid ratio of the aramid staple fiber to the poor solvent is 1:250-350 g / mL.

5. The method for preparing a radiative cooling and heat-conducting polyetheretherketone composite material according to claim 1, characterized in that: In step S2, the high-speed shearing is performed at a rotation speed of 500-1000 rpm for 10-12 hours.

6. The method for preparing a radiative cooling and heat-conducting polyetheretherketone composite material according to claim 1, characterized in that: In step S3, the mass ratio of the aramid fiber balls to the polyetheretherketone powder is 1-2:1-2.

7. The method for preparing a radiative cooling and heat-conducting polyetheretherketone composite material according to claim 1, characterized in that: In step S3, the hydroxyl-modified boron nitride accounts for 5%-50% of the total mass of the aramid fiber balls, polyetheretherketone powder and hydroxyl-modified boron nitride.

8. The method for preparing a radiation cooling and heat conducting polyetheretherketone composite material according to claim 1, characterized in that: In step S4, the melt hot pressing is performed at 3-5 MPa and 345-380° C. for pre-pressing for 10-15 minutes, and then the pressure is increased to 10-30 MPa and maintained for 8-20 minutes.

9. A radiation cooling and heat conducting polyetheretherketone composite material, prepared by the preparation method according to any one of claims 1 to 8.

10. Application of the radiative cooling and thermally conductive polyetheretherketone composite material according to claim 9 in the fields of military aviation, construction, energy and electronic packaging.

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