High-strength high-temperature-resistant anti-static polyether-ether-ketone composite material for electronic equipment and preparation method thereof

Abstract

The invention discloses a high-strength, high-temperature-resistant and anti-static polyether-ether-ketone composite material for electronic equipment and a preparation method of the high-strength, high-temperature-resistant and anti-static polyether-ether-ketone composite material. Comprising the following components in percentage by mass: 60%-70% of polyether-ether-ketone, 15%-20% of carbon fibers, 7%-10% of polytetrafluoroethylene, 3%-5% of boron nitride, 1%-3% of carbon nanotubes, 1%-2% of a silane coupling agent and 0.5%-1% of an antioxidant, and the sum of the mass percentages of all the components is 100%. When the prepared polyether-ether-ketone composite material is applied to electronic components, the mechanical strength, the thermal conductivity, the thermal stability, the chemical corrosion resistance and the antistatic property of the polyether-ether-ketone composite material can be further improved while the original excellent temperature resistance of the polyether-ether-ketone can be kept, so that the range of manufacturing and using the material as the electronic components is wider.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of high polymer materials, in particular to a high-strength high-temperature-resistant anti-static polyether ether ketone composite material for electronic equipment and a preparation method thereof. BACKGROUND

[0002] Polyether ether ketone (PEEK) has a high glass transition temperature (about 143℃) and a melting point (about 343℃), and can work stably for a long time in a high-temperature environment. It can be used for a long time in a high-temperature environment of 260℃, and can even withstand a high temperature above 300℃ for a short time. This excellent high-temperature resistance enables it to maintain good insulation performance and physical properties in some electronic devices with stringent temperature requirements, such as aerospace and automobile engine peripheral electronic components, without insulation failure or material deformation due to high temperature.

[0003] With the rapid development of electronic technology, electronic components such as servo motors and high-frequency connectors are increasingly used in high-temperature environments. In these application scenarios, higher requirements are placed on the insulation performance, high-temperature resistance, mechanical properties, and cleanliness of the materials. Polyether ether ketone materials have been widely used in the electronic field due to their excellent chemical stability, high and low temperature resistance, and insulation performance. However, the tensile strength, chemical corrosion resistance, and thermal conductivity of traditional unmodified polyether ether ketone materials need to be improved. They are easily oxidized and decomposed at high temperatures, are difficult to process, have a large dielectric constant, and are prone to signal loss and loss when used in high-frequency circuits, limiting their use in electronic components. Their anti-static performance cannot meet the requirements of semiconductor-level cleanliness.

[0004] Therefore, it is of great practical significance to develop a polyether ether ketone engineering plastic material that can meet the insulation requirements in high-temperature environments, has a reduced cost compared to pure polyether ether ketone, and has excellent tensile strength, chemical corrosion resistance, and anti-static performance. SUMMARY

[0005] The technical problem to be solved by the present application is to overcome the technical defects of the background art and provide a high-strength high-temperature-resistant anti-static polyether ether ketone composite material for electronic equipment and a preparation method thereof. The present application provides a polyether ether ketone composite material and a preparation method thereof, which can improve the mechanical strength, thermal conductivity, thermal stability, chemical corrosion resistance, and anti-static property of the material while maintaining the excellent temperature resistance of the original polyether ether ketone, making the material more widely used in the manufacture of electronic components.

[0006] The technical solution adopted by the present application to solve the above technical problems is as follows:

[0007] The high-strength high-temperature-resistant anti-static polyether ether ketone composite material for electronic equipment comprises the following components in percentage by mass: polyether ether ketone (PEEK) 60-70%, carbon fiber (CF) 15-20%, polytetrafluoroethylene (PTFE) 7-10%, boron nitride (BN) 3-5%, carbon nanotube (CNTs) 1-3%, silane coupling agent 1-2%, and antioxidant 0.5-1%, and the sum of the percentage by mass of each component is 100%.

[0008] Preferably, the polyether ether ketone has a medium-low viscosity, and more preferably, the viscosity is 300-700 Pa·s.

[0009] Preferably, the single-filament diameter of the carbon fiber is 5-10 μm.

[0010] Preferably, the particle size of the polytetrafluoroethylene is 20-40 μm.

[0011] Preferably, the diameter of the carbon nanotube is 3-5 μm.

[0012] Preferably, the silane coupling agent is KH560; treating the fiber surface with the silane coupling agent can enhance the interfacial bonding force between the carbon fiber and the polyether ether ketone matrix, and improve the overall performance and stability of the material.

[0013] Preferably, the antioxidant is antioxidant 1010 (primary antioxidant) and antioxidant 168 (auxiliary antioxidant), which can prevent the polyether ether ketone from being oxidatively degraded during high-temperature processing and use, and prolong the service life of the material.

[0014] More preferably, the antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a ratio of 1:1.

[0015] The preparation method of the high-strength high-temperature-resistant anti-static polyether ether ketone composite material for electronic equipment described above comprises the following steps:

[0016] (1) Matrix treatment: drying the polyether ether ketone powdery raw material;

[0017] (2) Filler treatment:

[0018] Carbon fiber (CF): surface treatment of carbon fiber by nitric acid oxidation;

[0019] Carbon nanotube / boron nitride (CNTs / BN): mixing carbon nanotube and boron nitride with silane coupling agent in a certain proportion, respectively, and adding the mixture into anhydrous ethanol for ultrasonic dispersion to ensure uniform dispersion of the nanofiller;

[0020] Polytetrafluoroethylene (PTFE): drying polytetrafluoroethylene powder;

[0021] (3) melt blending: using a co-rotating twin-screw extruder to melt blend the raw materials;

[0022] (4) molding granulation: water-cooling and cutting the extruded strip, and vacuum drying;

[0023] (5) injection molding / mold pressing: making the modified polyether ether ketone particles into products by injection / mold pressing;

[0024] (6) annealing treatment: eliminating internal stress;

[0025] (7) testing;

[0026] (8) machining;

[0027] (9) final testing;

[0028] (10) packaging.

[0029] Preferably, in step (1), the polyether ether ketone powdery raw material is dried, and is baked in an air circulation oven at 120±5℃ for 5-6h.

[0030] Preferably, in step (2), the carbon fiber is surface treated by nitric acid oxidation method, soaked in a 4% concentration nitric acid solution for 2h, then washed with deionized water until neutral, and baked at 80±5℃ for 12h to enhance the interface bonding force with the PEEK matrix.

[0031] Preferably, in step (2), the carbon nanotube and silane coupling agent are mixed in a ratio of 10:1, the boron nitride and silane coupling agent are mixed in a ratio of 5:1, then each is added to anhydrous ethanol and ultrasonically dispersed for 2h, then baked at 80±5℃, and the treated boron nitride and carbon nanotube are ball milled for 32h to ensure uniform dispersion of the nanofiller.

[0032] Preferably, in step (2), the primary antioxidant 1010 and the auxiliary antioxidant 168 are premixed in a ratio of 1:1, mixed by a high-speed mixer for 10-20min to ensure uniform distribution.

[0033] Preferably, in step (2), the polytetrafluoroethylene micro powder is dried at 80±5℃ for 4h to remove moisture and improve dispersibility.

[0034] Preferably, in step (3), the temperature settings during melt blending are:

[0035] Feed zone: 300℃, melting zone: 360-380℃, head: 350-360℃, mixing zone: 355-365℃.

[0036] Preferably, in step (3), the feeding strategy during melt blending is:

[0037] Main feeding: dry polyether ether ketone (PEEK) and premixed antioxidant;

[0038] Side feeding: pretreated carbon fiber (CF) and polytetrafluoroethylene (PTFE) micro powder (to prevent excessive shear fracture of the fiber);

[0039] Mixing zone: inject the mixed filler of treated carbon nanotubes / boron nitride (CNTs / BN) to ensure uniform dispersion.

[0040] Preferably, in step (3), the screw rotation speed during melt blending is 300-500 rpm (high shear zone for dispersing CNTs / BN, low shear zone for protecting CF length), and the vacuum degassing pressure is-0.8 MPa.

[0041] Preferably, in step (4), the temperature during vacuum drying is 80±5℃, and the time is 4h.

[0042] Preferably, in step (5), the injection molding process is as follows:

[0043] The feeding port temperature of the injection molding machine is maintained at 360-370℃, the nozzle temperature is controlled above 370℃, the mold temperature is 160-210℃, the injection pressure is 10-15 MPa, and the holding pressure is 5-10 MPa.

[0044] Preferably, in step (5), the compression molding process is as follows:

[0045] Place the mold in the oven and heat it to a temperature of 200-220℃, quickly remove the mold and place it on the press, put the modified polyether ether ketone (PEEK) particles into the preheated mold, close the mold and apply an initial pressure of 5 MPa to make the material flow initially; after heating to 360-380℃, pressurize to 10-25 MPa and hold for 20-30 min to ensure that the material is fully filled and solidified; gradually cool to room temperature and demold to obtain the product.

[0046] Preferably, in step (6), the annealing treatment conditions are 200℃ for 4h.

[0047] Compared with the prior art, the present application has the following advantages:

[0048] (1) The present application proposes a polyether ether ketone composite material and a preparation method thereof, which can improve the mechanical strength, thermal conductivity, thermal stability, chemical corrosion resistance and antistatic property of the material while maintaining the excellent temperature resistance of the original polyether ether ketone, making the material more widely used in the manufacture of electronic components.

[0049] (2) In order to meet the demand of wider use of electronic components, the application improves the comprehensive performance of polyether ether ketone by modifying the material; the application effectively improves the mechanical strength of the material (tensile strength ≥ 190 MPa, which is increased by more than 90% compared with pure polyether ether ketone) by adding carbon fibers in the polyether ether ketone resin; meanwhile, the thermal conductivity of the material is increased by more than 150% by the synergistic construction of the thermal conduction network of carbon fibers, carbon nanotubes and boron nitride, which improves the disadvantage of PEEK that is not conducive to the heat dissipation of high-power electronic components; in addition, the surface resistance of the material is reduced to 10 6 ~ 10 9 Ω by adding carbon nanotubes in the formula, which reduces the damage of static electricity to electronic components; the application can improve the dispersibility of carbon fibers and enhance the interfacial bonding force between carbon nanotubes and polyether ether ketone resin by using coupling agents, which reduces the agglomeration phenomenon; the application improves the flowability of polyether ether ketone processing by adding polytetrafluoroethylene, which effectively reduces the cost of PEEK material for electronic components. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 is the preparation process flow chart of the polyether ether ketone composite material of the application. DETAILED DESCRIPTION

[0051] In order to better understand the content of the application, the following further describes in combination with specific examples and drawings. It should be understood that these examples are only used to further illustrate the application, and are not used to limit the scope of the application. In addition, it should be understood that after reading the content described in the application, the person skilled in the art makes some non-essential modifications or adjustments to the application, which still belongs to the protection scope of the application.

[0052] Example 1

[0053] 1. Formula: PEEK powder 70wt% (viscosity 500Pa·s), CF 15wt% (single filament diameter 7μm), PTFE micro powder 7wt% (particle size 20μm), BN 4wt%, CNTs 2wt% (diameter 3μm), silane coupling agent KH560 1wt%, antioxidant 101 0.5wt%, antioxidant 168 0.5wt%.

[0054] 2. Preparation process (see the preparation process flow chart of the polyether ether ketone composite material of the application in Figure 1 ):

[0055] (1) Matrix treatment: dry the polyether ether ketone powdery raw material, and bake in an air circulation oven at 120±5℃ for 5-6h.

[0056] (2) Filler treatment:

[0057] Carbon fiber (CF): The carbon fiber was surface treated by nitric acid oxidation method, immersed in 4% concentration nitric acid solution for 2h, then washed with deionized water to neutral, and dried at 80±5℃ for 12h to enhance the interfacial bonding force with PEEK matrix;

[0058] Carbon nanotube / boron nitride (CNTs / BN): Carbon nanotubes and silane coupling agent KH560 were mixed at a ratio of 10:1, boron nitride and silane coupling agent KH560 were mixed at a ratio of 5:1, then each was added to anhydrous ethanol and ultrasonically dispersed for 2h, then dried at 80±5℃, and the treated boron nitride and carbon nanotubes were ball milled for 32h to ensure uniform dispersion of the nanofiller;

[0059] Antioxidant: The main antioxidant 1010 and the auxiliary antioxidant 168 were premixed at a ratio of 1:1, mixed by a high-speed blender for 10-20min to ensure uniform distribution;

[0060] Polytetrafluoroethylene (PTFE): Polytetrafluoroethylene micro powder was dried at 80±5℃ for 4h to remove moisture and improve dispersibility;

[0061] (3) Melt blending: The raw materials were melt blended using a co-rotating twin screw extruder;

[0062] Temperature setting during melt blending:

[0063] Feed zone: 300℃, melting zone: 360℃, die: 350℃, mixing zone: 365℃;

[0064] Feeding strategy during melt blending:

[0065] Main feeding: dried PEEK + premixed antioxidant;

[0066] Side feeding: pretreated CF and PTFE micro powder (to prevent excessive shear fracture of fibers);

[0067] Mixing zone: injection of treated CNTs / BN mixed filler to ensure uniform dispersion;

[0068] Screw speed during melt blending was 300-500rpm (high shear zone for dispersing CNTs / BN, low shear zone to protect CF length), vacuum degassing pressure was -0.8MPa;

[0069] (4) Forming and granulation: extruded strip water cooling and pelletizing, 80±5℃ vacuum drying for 4h;

[0070] (5) Injection molding: modified polyether ether ketone particles were made into products by injection molding, with the aid of mold release agent for demolding;

[0071] The process of injection molding is as follows:

[0072] The feeding port temperature of the injection molding machine is maintained at 360-370°C; the nozzle temperature is controlled at 380°C, the mold temperature is 160-210°C; the injection pressure is 10 MPa; the pressure maintaining pressure is 5-10 MPa;

[0073] (6) Annealing treatment: 200°C, annealing for 4h, eliminating internal stress;

[0074] (7) Detection;

[0075] (8) Machining;

[0076] (9) Final detection;

[0077] (10) Packaging.

[0078] Example 2

[0079] According to the specific steps of Example 1, the difference is that the material formula is changed to PEEK powder 65wt%, CF 18wt%, PTFE micro powder 7wt%, BN 5wt%, CNTs 3wt%, silane coupling agent KH560 1wt%, antioxidant 10100.5wt%, antioxidant 1680.5wt%.

[0080] Example 3

[0081] According to the specific steps of Example 1, the difference is that the hot forming method is changed to die forming, and the die forming process is as follows:

[0082] Put the mold into the oven and heat, the heating temperature is 200-220°C, quickly take out the mold and put it on the press, put the modified PEEK particles into the preheated mold, close the mold and apply an initial pressure of 5MPa, make the material flow initially; after heating to 380°C, press to 20MPa, pressure maintaining for 20min, ensure that the material is fully filled and solidified; gradient cooling to room temperature, demolding to get the product.

[0083] Example 4

[0084] According to the specific steps of Example 2, the difference is that the hot forming method is changed to die forming, and the die forming process is as follows:

[0085] Put the mold into the oven and heat, the heating temperature is 200-220°C, quickly take out the mold and put it on the press, put the modified PEEK particles into the preheated mold, close the mold and apply an initial pressure of 5MPa, make the material flow initially; after heating to 380°C, press to 20MPa, pressure maintaining for 20min, ensure that the material is fully filled and solidified; gradient cooling to room temperature, demolding to get the product.

[0086] Comparative Example 1

[0087] The specific steps of Example 1 were followed, except that the formulation was changed to: polyether ether ketone 100 wt%.

[0088] Comparative Example 2

[0089] The specific steps of Example 3 were followed, except that the formulation was changed to: polyether ether ketone 100 wt%.

[0090] The physical properties of the polyether ether ketone composite materials prepared in Examples 1-3 and Comparative Examples 1-2 above are shown in Table 2. The test standard for tensile strength is ISO 527, the test standard for surface resistance is IEC 60093, and the test standard for thermal conductivity is ASTM D5470-17.

[0091] Table 2 Physical properties of polyether ether ketone composite materials prepared in Examples 1-3 and Comparative Examples 1-2

[0092] Examples Tensile strength / MPa Surface resistance / Ω Thermal conductivity / W / (m K) Example 1 190 10 9 ]] 1.2 Example 2 203 10 6 ]] 1.4 Example 3 192 10 9 ]] 1.3 Example 4 205 10 6 ]] 1.3 Comparative Example 1 92 10 16 ]] 0.4 Comparative Example 2 93 10 16 ]] 0.4

[0093] As can be seen from Table 2, the surface resistance of the modified polyether ether ketone composite material (Examples 1, 2, 3, 4) decreases, and the thermal conductivity increases significantly. Among them, Example 1 and Example 3 respectively use injection molding and compression molding process, and from the results it can be seen that the two molding methods have little effect on the wear and thermal properties of the material. The polyether ether ketone composite material prepared by the present application not only has excellent mechanical strength and antistatic properties, but also is compatible with various molding processes such as injection molding and compression molding, and can realize large-scale production. Its tensile strength is increased by more than 90% compared to pure polyether ether ketone, and its thermal conductivity is increased by more than 50%, which can endow it with antistatic properties, solve the problem of static accumulation leading to dust adsorption, discharge damage and even explosion risk, and provide a high-performance, high-heat-resistant, high-antistatic material solution for the electronic and semiconductor industry, medical and life science, aerospace and automotive industry.

[0094] The application discloses a high-strength high-temperature-resistant anti-static polyether ether ketone (PEEK) composite material for electronic equipment, which comprises the following components in percentage by mass: polyether ether ketone (PEEK) 60-70%, carbon fiber (CF) 15-20%, polytetrafluoroethylene (PTFE) 7-10%, boron nitride (BN) 3-5%, carbon nanotube (CNTs) 1-3%, silane coupling agent 1-2%, and antioxidant 0.5-1%, and the sum of the percentage by mass of the components is 100%; the components are blended and granulated through a double-screw extruder, and then injection molding or die molding is performed to obtain the high-strength high-temperature-resistant anti-static polyether ether ketone (PEEK) composite material. 6 ~10 9 Ω, reduces the damage of static electricity to electronic components; the use of the coupling agent can improve the dispersibility of the carbon fiber, enhances the interfacial bonding force between the carbon nanotube and the polyether ether ketone resin, and reduces the agglomeration phenomenon; the addition of the polytetrafluoroethylene improves the flowability of the polyether ether ketone processing, and effectively reduces the cost of the PEEK material for electronic components.

[0095] The above description is not a limitation of the application, and the application is not limited to the above examples. Changes, modifications, additions or replacements made by ordinary skilled in the technical field within the essential scope of the application shall also fall within the protection scope of the application.

Claims

1. A high-strength, high-temperature resistant, anti-static polyether ether ketone composite material for electronic equipment, characterized in that, By mass percentage, the following components are included: polyether ether ketone 60-70%, carbon fiber 15-20%, polytetrafluoroethylene 7-10%, boron nitride 3-5%, carbon nanotube 1-3%, silane coupling agent 1-2%, antioxidant 0.5-1%, and the sum of the mass percentages of the components is 100%.

2. A high strength, high temperature resistant, anti-static polyether ether ketone composite material for electronic devices as claimed in claim 1, wherein, The polyether ether ketone has a medium-low viscosity; the carbon fiber has a single-filament diameter of 5-10 μm; the polytetrafluoroethylene has a particle size of 20-40 μm; and the carbon nanotube has a diameter of 3-5 μm.

3. A high strength, high temperature resistant, anti-static polyether ether ketone composite material for electronic devices as claimed in claim 1, wherein, The silane coupling agent is KH560.

4. A high-strength, high-temperature resistant, anti-static polyether ether ketone composite material for electronic equipment according to claim 1, characterized in that, The antioxidant is a compound of antioxidant 1010 and antioxidant 168.

5. A method for preparing high-strength high-temperature-resistant anti-static polyether ether ketone composite material for electronic equipment according to any one of claims 1 to 4, characterized in that, The method comprises the following steps: (1) Base treatment: drying the polyether ether ketone in powder form; (2) Filler treatment: Carbon fiber: surface treatment of the carbon fiber by nitric acid oxidation; Carbon nanotube / boron nitride: mixing the carbon nanotube and the boron nitride with the silane coupling agent in a certain proportion, respectively, and adding the mixtures into anhydrous ethanol for ultrasonic dispersion to ensure uniform dispersion of the nanofillers; Polytetrafluoroethylene: drying the polytetrafluoroethylene powder; (3) Melt blending: melt blending of the raw materials by using a co-rotating twin-screw extruder; (4) Granulation: water-cooling and pelletizing of the extruded strip, and vacuum drying; (5) Injection molding / mold pressing: preparation of the modified polyether ether ketone particles into products by injection molding / mold pressing; (6) Annealing treatment: elimination of internal stress.

6. A process for the preparation of high strength high temperature resistant anti-static polyether ether ketone composite material for electronic devices as claimed in claim 5 wherein, In step (2), the carbon fiber is surface treated by nitric acid oxidation, soaked in a 4% concentration nitric acid solution for 2 h, then washed with deionized water until neutral, and dried at 80±5℃ for 12 h.

7. A process for the preparation of high strength high temperature resistant anti-static polyether ether ketone composite material for electronic devices as claimed in claim 5 wherein, In step (2), the carbon nanotube and the silane coupling agent are mixed in a 10:1 ratio, the boron nitride and the silane coupling agent are mixed in a 5:1 ratio, then each is added into anhydrous ethanol, ultrasonic dispersed for 2 h, then dried at 80±5℃, and the treated boron nitride and carbon nanotube are ball milled for 32 h to ensure uniform dispersion of the nanofillers.

8. A process for the preparation of high strength high temperature resistant anti-static polyether ether ketone composite material for electronic devices as claimed in claim 5 wherein, In step (2), the antioxidant 1010 and the antioxidant 168 are premixed in a 1:1 ratio, mixed by a high-speed mixer for 10-20 min to ensure uniform distribution.

9. A process for the preparation of high strength high temperature resistant anti-static polyether ether ketone composite material for electronic devices as claimed in claim 5 wherein, In step (3), the temperature settings during melt blending are as follows: Feeding zone: 300℃, melting zone: 360-380℃, head: 350-360℃, mixing zone: 355-365℃; Feeding strategy during melt blending: Main feeding: dried polyether ether ketone and premixed antioxidant; Side feeding: pretreated carbon fiber and polytetrafluoroethylene powder; Mixing zone: injection of the mixed filler of treated carbon nanotube / boron nitride to ensure uniform dispersion.

10. A process for the preparation of high strength high temperature resistant anti-static polyether ether ketone composite material for electronic devices as claimed in claim 5 wherein, In step (5), the process of injection molding is as follows: ​ The feeding port temperature of the injection molding machine is kept at 360-370℃; the nozzle temperature is controlled above 370℃, the mold temperature is 160-210℃; the injection pressure is 10-15 MPa; and the holding pressure is 5-10 MPa; The process of mold pressing is as follows: The mold is heated in the oven at a temperature of 200-220 °C, and the mold is quickly removed and placed on a press. The modified polyether ether ketone particles are placed in the preheated mold, the mold is closed, and an initial pressure of 5 MPa is applied to cause the material to initially flow. The temperature is increased to 360-380 °C, and the pressure is increased to 10-25 MPa. The pressure is maintained for 20-30 min to ensure that the material is fully filled and solidified. The temperature is gradually decreased to room temperature, and the product is removed from the mold.

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