Preparation method of polyphenylene sulfide antenna window

Abstract

The invention relates to the technical field of radar antenna composite materials, and discloses a polyphenylene sulfide antenna window preparation method, which comprises: uniformly mixing polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber and silicone oil, and carrying out ball milling to obtain polyphenylene sulfide injection molding powder; performing drying; performing injection molding; after demolding, polishing the flash to obtain an antenna window blank; uniformly mixing polyphenylene sulfide, hydrophobic silicon dioxide, titanium dioxide and a silane coupling agent, and performing ball milling to obtain polyphenylene sulfide coating powder; dispersing in absolute ethyl alcohol to form a polyphenylene sulfide suspension coating; and placing the antenna window blank in the polyphenylene sulfide suspension coating, taking out the antenna window blank, curing, and performing cold treatment to obtain the polyphenylene sulfide antenna window. Drying the polyphenylene sulfide antenna window; and polishing the outer surface. According to the preparation method of the polyphenylene sulfide antenna window, the prepared antenna window has relatively high waterproofness and humidity and heat resistance, and relatively low dielectric constant and loss angle tangent.

Description

Technical Field

[0001] This invention relates to the field of radar antenna composite materials technology, and specifically to a method for preparing a polyphenylene sulfide antenna window. Background Technology

[0002] Radar radomes / antenna windows are crucial components of modern missiles. As electromagnetic wave transmission barriers for missile radar systems, they protect the antenna from harsh external environments and maintain its normal operation. Antenna windows require excellent dielectric properties, mechanical strength, heat resistance, and impact resistance. The manufacturing complexity of antenna windows must also be a key consideration.

[0003] Currently, thermoplastic resins such as polytetrafluoroethylene (PTFE) are used in China to process radomes / antenna windows, but the mainstream PTFE antenna windows have the following problems: High processing defect rate: Polytetrafluoroethylene has a high melting temperature, and porosity is generated due to high-temperature degradation during injection molding, resulting in large fluctuations in dielectric constant; Poor surface moisture resistance: The contact angle of polytetrafluoroethylene is still insufficient to resist high humidity environments, and the dielectric loss soars after humid heat aging.

[0004] Polyphenylene sulfide is a highly crystalline aryl sulfur polymer, belonging to thermoplastic resins. It has a low dielectric constant, loss tangent, good dimensional stability, is not easily deformed, and has a low water absorption rate. However, the high glass fiber content leads to a large surface roughness, which increases electromagnetic wave scattering. Without a moisture barrier, it has a high moisture absorption rate and a large dielectric constant drift in environmental tests in the South China Sea. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of the above-mentioned technologies by providing a method for preparing a polyphenylene sulfide antenna window. The prepared antenna window has high water resistance, resistance to damp heat, low dielectric constant, and loss tangent.

[0006] To achieve the above objectives, the method for preparing the polyphenylene sulfide antenna window designed in this invention includes the following steps: 1) Mix polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber, and silicone oil in a weight ratio of 110~90:40~20:12~8:1.5~2.5 until homogeneous, and then ball mill at 250~350 r / min for 2.5~3.5 h to obtain polyphenylene sulfide injection molding powder; 2) Polyphenylene sulfide injection molding powder is kept at 80~110℃ for 2~3 hours, and then dried at 150~180℃ for 2~4 hours; 3) Add the dried polyphenylene sulfide injection molding powder to the injection molding machine and injection mold it at a melt temperature of 300~350℃, a nozzle temperature of 320~340℃, a mold temperature of 130~150℃, and an injection pressure of 80~130MPa. The molding cycle is 25~35s. 4) After demolding, the flash is ground off to obtain the antenna window blank; 5) Mix polyphenylene sulfide, hydrophobic silica, titanium dioxide, and silane coupling agent in a weight ratio of 100:100:20:1 until homogeneous, and ball mill at 250~350 r / min for 2.5~3.5 h to obtain polyphenylene sulfide coating powder; 6) Disperse the polyphenylene sulfide coating powder in anhydrous ethanol and stir evenly to form a polyphenylene sulfide suspension coating with a solid-liquid ratio of 1:4 to 1:6. 7) Place the antenna window blank in a polyphenylene sulfide suspension coating, remove it after 8-12 minutes, cure it at 280-300℃ for 20-30 minutes, remove it after curing, and place it in high-purity water at room temperature for 20-30 minutes for cold treatment to obtain the polyphenylene sulfide antenna window. 8) Place the polyphenylene sulfide antenna window in an oven at 40~60℃ and dry for 1.5~2.5 hours; 9) After drying, the outer surface is polished.

[0007] Preferably, in step 1), the weight ratio of polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber, and silicone oil is 100:30:10:2.

[0008] Preferably, in step 1), the ball mill speed is 300 r / min and the ball milling time is 3 h.

[0009] Preferably, in step 2), the heat preservation temperature is 100℃, the heat preservation time is 2.5 hours, the drying temperature is 170℃, and the drying time is 3 hours.

[0010] Preferably, in step 3), the melt temperature is 320°C, the nozzle temperature is 330°C, the mold temperature is 140°C, the injection pressure is 100MPa, and the molding cycle is 30s.

[0011] Preferably, in step 4), the residual flash after injection molding is sanded smooth and flat using 300-400 grit sandpaper.

[0012] Preferably, in step 5), the weight ratio of polyphenylene sulfide, hydrophobic silica, titanium dioxide, and silane coupling agent is 110~90:110~90:15~25:1, the ball mill speed is 300 r / min, and the ball milling time is 3 h.

[0013] Preferably, in step 7), the antenna window blank is soaked for 10 minutes, cured at 290°C for 25 minutes, and cooled for 25 minutes.

[0014] Preferably, in step 8), the drying temperature is 50°C and the drying time is 2 hours.

[0015] Preferably, in step 9), the outer surface of the polyphenylene sulfide antenna window is polished smooth and flat using 300-400 grit sandpaper.

[0016] Compared with the prior art, the present invention has the following advantages: 1. The antenna window, after being modified with glass fiber and polytetrafluoroethylene, exhibits significantly improved wear resistance and heat resistance, good moisture and water resistance, resistance to damp heat and corrosion, and low dielectric constant and loss tangent. 2. The molding process is simple; 3. It has high product consistency, and the size of the product is controlled by the mold. The production process is fast and efficient, and it is suitable for mass production. Detailed Implementation

[0017] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1 A method for preparing a polyphenylene sulfide antenna window includes the following steps: 1) Mix polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber, and silicone oil in a weight ratio of 100:30:0:2 until homogeneous, and then ball mill at 300 r / min for 3 h to obtain polyphenylene sulfide injection molding powder. 2) Polyphenylene sulfide injection molding powder is kept at 100℃ for 2.5 hours and then dried at 170℃ for 3 hours; 3) Add the dried polyphenylene sulfide injection molding powder to the injection molding machine and injection mold it at a melt temperature of 320℃, a nozzle temperature of 330℃, a mold temperature of 140℃, and an injection pressure of 100MPa. The molding cycle is 300s. 4) After demolding, use 300-grit sandpaper to smooth and flatten the residual flash after injection molding to obtain the antenna window blank; 5) Mix polyphenylene sulfide, hydrophobic silica, titanium dioxide and silane coupling agent in a weight ratio of 100:100:20:1 evenly, and ball mill at 300 r / min for 3 h to obtain polyphenylene sulfide coating powder. 6) Disperse the polyphenylene sulfide coating powder in anhydrous ethanol and stir evenly to form a polyphenylene sulfide suspension coating with a solid-liquid ratio of 1:4; 7) Place the antenna window blank in a polyphenylene sulfide suspension coating, remove it after 10 minutes, cure it at 290℃ for 25 minutes, remove it after curing, and place it in high-purity water at room temperature for 25 minutes for cold treatment to obtain the polyphenylene sulfide antenna window. 8) Place the polyphenylene sulfide antenna window in an oven at 50°C for 2 hours to dry; 9) After drying, use 300-grit sandpaper to smooth and flatten the outer surface of the polyphenylene sulfide antenna window.

[0019] The polyphenylene sulfide matrix antenna window prepared in this embodiment has a moisture absorption rate of 0.45%, a dielectric constant of 3.54 at 9313MHz, and a loss tangent of 6.3*10⁻⁶. -3 The surface is smooth and free of pits.

[0020] Example 2 A method for preparing a polyphenylene sulfide antenna window includes the following steps: 1) Mix polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber, and silicone oil in a weight ratio of 110:40:12:1.5 until homogeneous, and then ball mill at 250 r / min for 3.5 h to obtain polyphenylene sulfide injection molding powder. 2) Polyphenylene sulfide injection molding powder is kept at 80℃ for 3 hours and then dried at 150℃ for 4 hours; 3) Add the dried polyphenylene sulfide injection molding powder to the injection molding machine and injection mold it at a melt temperature of 300℃, a nozzle temperature of 340℃, a mold temperature of 130℃, and an injection pressure of 80MPa. The molding cycle is 35s. 4) After demolding, use 400-grit sandpaper to smooth and flatten the residual flash after injection molding to obtain the antenna window blank; 5) Mix polyphenylene sulfide, hydrophobic silica, titanium dioxide and silane coupling agent in a weight ratio of 110:110:15:1 and mix evenly. Then, ball mill the mixture at 250 r / min for 3.5 h to obtain polyphenylene sulfide coating powder. 6) Disperse the polyphenylene sulfide coating powder in anhydrous ethanol and stir evenly to form a polyphenylene sulfide suspension coating with a solid-liquid ratio of 1:6; 7) Place the antenna window blank in a polyphenylene sulfide suspension coating, remove it after 8 minutes, cure it at 280℃ for 30 minutes, remove it after curing, and place it in high-purity water at room temperature for 20 minutes for cold treatment to obtain the polyphenylene sulfide antenna window. 8) Place the polyphenylene sulfide antenna window in an oven at 40°C and dry for 2.5 hours; 9) After drying, use 400-grit sandpaper to smooth and flatten the outer surface of the polyphenylene sulfide antenna window.

[0021] The polyphenylene sulfide matrix antenna window prepared in this embodiment has a moisture absorption rate of 0.46%, a dielectric constant of 3.52 at 9313MHz, and a loss tangent of 6.25*10⁻⁶. -3 The surface is smooth and free of pits.

[0022] Example 3 A method for preparing a polyphenylene sulfide antenna window includes the following steps: 1) Mix polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber, and silicone oil in a weight ratio of 90:20:2.5 until homogeneous, and then ball mill at 350 r / min for 2.5 h to obtain polyphenylene sulfide injection molding powder; 2) Polyphenylene sulfide injection molding powder is kept at 110℃ for 2 hours and then dried at 180℃ for 2 hours; 3) Add the dried polyphenylene sulfide injection molding powder to the injection molding machine and injection mold it at a melt temperature of 350℃, a nozzle temperature of 320℃, a mold temperature of 150℃, and an injection pressure of 130MPa. The molding cycle is 25s. 4) After demolding, use 300-grit sandpaper to smooth and flatten the residual flash after injection molding to obtain the antenna window blank; 5) Mix polyphenylene sulfide, hydrophobic silica, titanium dioxide and silane coupling agent in a weight ratio of 90:90:25:1 until uniform, and ball mill at 350 r / min for 2.5 h to obtain polyphenylene sulfide coating powder. 6) Disperse the polyphenylene sulfide coating powder in anhydrous ethanol and stir evenly to form a polyphenylene sulfide suspension coating with a solid-liquid ratio of 1:5; 7) Place the antenna window blank in a polyphenylene sulfide suspension coating, remove it after 12 minutes, cure it at 300℃ for 20 minutes, remove it after curing, and place it in high-purity water at room temperature for 30 minutes for cold treatment to obtain the polyphenylene sulfide antenna window. 8) Place the polyphenylene sulfide antenna window in an oven and dry it at 60°C for 1.5 hours; 9) After drying, use 300-grit sandpaper to smooth and flatten the outer surface of the polyphenylene sulfide antenna window.

[0023] The polyphenylene sulfide matrix antenna window prepared in this embodiment has a moisture absorption rate of 0.447%, a dielectric constant of 3.57 at 9313MHz, and a loss tangent of 6.36*10⁻⁶. -3 The surface is smooth and free of pits.

[0024] Example 4 A method for preparing a polyphenylene sulfide antenna window includes the following steps: 1) Mix polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber and silicone oil in a weight ratio of 80:35:10:2 evenly, and ball mill at 280 r / min for 3 h to obtain polyphenylene sulfide injection molding powder. 2) Polyphenylene sulfide injection molding powder is kept at 90℃ for 2 hours, and then dried at 160℃ for 3 hours; 3) Add the dried polyphenylene sulfide injection molding powder to the injection molding machine and injection mold it at a melt temperature of 320℃, a nozzle temperature of 330℃, a mold temperature of 140℃, and an injection pressure of 120MPa. The molding cycle is 30s. 4) After demolding, use 300-grit sandpaper to smooth and flatten the residual flash after injection molding to obtain the antenna window blank; 5) Mix polyphenylene sulfide, hydrophobic silica, titanium dioxide and silane coupling agent in a weight ratio of 95:105:10:1 evenly, and ball mill at 270 r / min for 3 h to obtain polyphenylene sulfide coating powder. 6) Disperse the polyphenylene sulfide coating powder in anhydrous ethanol and stir evenly to form a polyphenylene sulfide suspension coating with a solid-liquid ratio of 1:5; 7) Place the antenna window blank in a polyphenylene sulfide suspension coating, remove it after 9 minutes, cure it at 285℃ for 25 minutes, remove it after curing, and place it in high-purity water at room temperature for 25 minutes for cold treatment to obtain the polyphenylene sulfide antenna window. 8) Place the polyphenylene sulfide antenna window in an oven and dry it at 450℃ for 2 hours; 9) After drying, use 400-grit sandpaper to smooth and flatten the outer surface of the polyphenylene sulfide antenna window.

[0025] The polyphenylene sulfide matrix antenna window prepared in this embodiment has a moisture absorption rate of 0.448%, a dielectric constant of 3.54 at 9313MHz, and a loss tangent of 6.29*10⁻⁶. -3 The surface is smooth and free of pits.

[0026] The antenna window prepared by the method of the present invention, after modification with glass fiber and polytetrafluoroethylene, has significantly improved wear resistance and heat resistance, good moisture and water resistance, resistance to damp heat and corrosion, and low dielectric constant and loss tangent. The molding process is simple, and the product has high consistency. The size of the product can be controlled by the mold, and the production process is fast and efficient, making it suitable for mass production.

[0027] It should be noted that the above description of the technical solutions is exemplary, and this specification may be embodied in different forms and should not be construed as limiting it to the technical solutions set forth herein. Rather, providing these descriptions will ensure that the disclosure of this invention is thorough and complete, and will fully convey the scope of this specification to those skilled in the art. Furthermore, the technical solutions of this invention are defined only by the scope of the claims. Features of various embodiments of this invention may be combined or spliced ​​together in part or in whole, and may be implemented in various different configurations as will be fully understood by those skilled in the art. Embodiments of this invention may be implemented independently of each other or may be implemented together in an interdependent relationship.

[0028] For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and the above structures should all be considered to fall within the protection scope of the present invention.

Claims

1. A method of making a polyphenylene sulfide antenna window, the method comprising: The method comprises the following steps: ​ 1) uniformly mixing polyphenylene sulfide powder, polytetrafluoroethylene powder, glass fiber and silicone oil in a weight ratio of 110-90:40-20:12-8:1.5-2.5, ball milling for 2.5-3.5 hours at 250-350 r / min by using a ball mill to obtain polyphenylene sulfide injection molding powder; 2) heat treating the polyphenylene sulfide injection molding powder at 80-110 DEG C for 2-3 hours, and then drying the polyphenylene sulfide injection molding powder at 150-180 DEG C for 2-4 hours; 3) injecting molding the dried polyphenylene sulfide injection molding powder by using an injection molding machine at a melting temperature of 300-350 DEG C, a nozzle temperature of 320-340 DEG C, a mold temperature of 130-150 DEG C, and an injection molding pressure of 80-130 MPa, and the molding cycle is 25-35 seconds; 4) polishing the flash after demolding to obtain an antenna window blank; 5) uniformly mixing polyphenylene sulfide, hydrophobic silicon dioxide, titanium dioxide and silane coupling agent in a weight ratio of 110-90:110-90:15-25:1, ball milling for 2.5-3.5 hours at 250-350 r / min by using a ball mill to obtain polyphenylene sulfide coating powder; 6) uniformly stirring the polyphenylene sulfide coating powder in anhydrous ethanol to form a polyphenylene sulfide suspension coating, and the solid-liquid ratio is 1:4-1:6; 7) placing the antenna window blank in the polyphenylene sulfide suspension coating, taking out after 8-12 minutes, curing at 280-300 DEG C for 20-30 minutes, taking out after the curing is completed, and cold treating in room temperature high-purity water for 20-30 minutes to obtain a polyphenylene sulfide antenna window; 8) drying the polyphenylene sulfide antenna window in an oven at 40-60 DEG C for 1.5-2.5 hours; 9) polishing the outer surface after the drying is completed.

2. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 1), the weight ratio of the polyphenylene sulfide powder, the polytetrafluoroethylene powder, the glass fiber and the silicone oil is 100:30:10:

2.

3. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 1), the ball mill rotates at 300 r / min, and the ball milling time is 3 hours.

4. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 2), the heat treatment temperature is 100 DEG C, the heat treatment time is 2.5 hours, the drying temperature is 170 DEG C, and the drying time is 3 hours.

5. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 3), the melting temperature is 320 DEG C, the nozzle temperature is 330 DEG C, the mold temperature is 140 DEG C, the injection molding pressure is 100 MPa, and the molding cycle is 30 seconds.

6. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 4), the residual flash after the injection molding is polished smooth and flat by using 300-400 mesh sandpaper.

7. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 5), the weight ratio of the polyphenylene sulfide, the hydrophobic silicon dioxide, the titanium dioxide and the silane coupling agent is 100:100:20:1, the ball mill rotates at 300 r / min, and the ball milling time is 3 hours.

8. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 7), the antenna window blank is soaked for 10 minutes, the curing temperature is 290 DEG C, the curing time is 25 minutes, and the cold treatment time is 25 minutes.

9. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 8), the drying temperature is 50 DEG C, and the drying time is 2 hours.

10. The method for preparing the polyphenylene sulfide antenna window as described in claim 1, characterized in that: In the step 9), the outer surface of the polyphenylene sulfide antenna window is polished smooth and flat by using 300-400 mesh sandpaper.