A high and low temperature resistant, acid and alkali resistant, radiation resistant wave-transparent polyphenylene sulfide composite material and a preparation method thereof

Abstract

The application provides a high and low temperature resistant, acid and alkali resistant, and radiation resistant wave-transparent polyphenylene sulfide composite material, which is made of the following raw materials in parts by weight: polyphenylene sulfide resin 40-65 parts, high-density polystyrene resin 10-25 parts, low-dielectric glass fiber 15-35 parts, compatibility agent 3-8 parts, low-dielectric filler 10-25 parts, lubricant 1-3 parts, compatibilizer 3-6 parts, and antioxidant 1-2 parts. The application also discloses a preparation method of the wave-transparent polyphenylene sulfide composite material. The wave-transparent polyphenylene sulfide composite material provided by the application can meet the strict requirements of performance of wave-transparent materials in special environment fields such as aerospace, intelligent driving of automobiles, 5G / 6G communication and chemical industry.

Description

Technical Field

[0001] This invention relates to a composite material, and more particularly to a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis, and radiation, and its preparation method. Background Technology

[0002] In the aerospace field, aircraft must withstand extreme high and low temperature environments—from the high temperatures of the Earth's surface to the low temperatures of space. Materials must maintain stable performance to ensure the safe operation of the aircraft. Simultaneously, during rocket launches and other processes, materials may also be subject to corrosion from acidic and alkaline gases and intense radiation. In the field of autonomous driving, automated driving systems must cope with various climatic environments and weather conditions. Stable, highly sensitive signal acquisition and timely signal transmission are fundamental conditions for automated driving, and materials must maintain stable performance to ensure safe operation. In the chemical industry, chemical reactions often take place under harsh conditions, such as high temperature, high pressure, and strong acid and alkali environments, placing extremely high demands on the acid and alkali resistance and high temperature resistance of materials.

[0003] Furthermore, with the development of communication technology, the demand for wave-transparent materials is increasing, especially in the fields of 5G and 6G communications and autonomous driving. Wave-transparent materials ensure the smooth transmission of communication signals. Therefore, developing materials with resistance to high and low temperatures, acids and alkalis, radiation resistance, and wave transmission properties has significant practical importance and broad development prospects. These materials can not only improve the performance of equipment in aerospace, autonomous driving, 5G, 6G communications, and chemical industries, but also drive technological progress in related industries.

[0004] Existing microwave-transparent materials suffer from problems such as high raw material costs, difficult processing, narrow temperature resistance, sensitivity to acid and alkali corrosion, poor radiation stability, or high manufacturing costs. Currently, while some materials on the market exhibit good performance in one or several aspects, their manufacturing processes are very difficult (manufacturing temperatures of 360-400℃, which are difficult to process with general equipment), and material costs are high (polyetheretherketone (PEEK) and polyimide are expensive). For example, alloys of PEEK and PPS, or polyimide and PPS, are rarely produced simultaneously while meeting the requirements for high and low temperature resistance, acid and alkali resistance, radiation resistance, and microwave transmission performance, and can be manufactured efficiently and cost-effectively. For instance, the performance of some high-temperature resistant materials deteriorates significantly in acidic and alkaline environments, while some acid and alkali resistant materials cannot withstand extreme temperatures or radiation. Regarding microwave transmission performance, although many materials have a certain degree of microwave transmission capability, their performance is affected in complex environments. Polyphenylene sulfide (PPS), as a high-performance special engineering plastic, possesses certain heat resistance and chemical corrosion resistance, but PPS material alone cannot simultaneously meet so many specific performance requirements. Therefore, developing a PPS-based composite material, through reasonable modification methods, that simultaneously possesses resistance to high and low temperatures, acids and alkalis, radiation resistance, and wave transmission properties, has significant invention value and practical application needs. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis, and radiation, which can meet the stringent requirements for material performance in special environmental fields such as aerospace, autonomous driving, 5G / 6G communication, and chemical industry.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0007] A microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis, and radiation is made from the following raw materials in parts by weight: 40-65 parts polyphenylene sulfide resin, 10-25 parts high-density polystyrene resin, 15-35 parts low-dielectric glass fiber, 3-8 parts compatibilizer, 10-25 parts low-dielectric filler, 1-3 parts lubricant, 3-6 parts compatibilizer, and 1-2 parts antioxidant.

[0008] Furthermore, the melt flow rate of the polyphenylene sulfide resin described in this invention is 1000-1500 g / 10 min, and the test conditions are 316℃ and 5 kg. This invention chooses polyphenylene sulfide as the matrix material primarily due to its excellent wave transmission and numerous superior properties: Structurally, polyphenylene sulfide is a linear polymer composed of alternating benzene rings and sulfur atoms, a unique structure that endows it with high stability; in terms of performance, it exhibits significant crystallinity and excellent thermal stability, with a heat distortion temperature exceeding 260℃, maintaining structural stability and resisting decomposition even at high temperatures. In addition, it possesses excellent chemical corrosion resistance, exhibiting strong resistance to most acids, alkalis, and organic solvents. In this invention, polyphenylene sulfide, as the matrix, provides the composite material with fundamental thermal stability, chemical corrosion resistance, and certain mechanical properties, making it a key component in constructing the performance framework of the composite material.

[0009] Furthermore, the density of the high-density polystyrene resin described in this invention is 1.05-1.10 g / cm³. 3 This invention selects high-density polystyrene to further optimize the performance of the composite material. Its relatively high density and excellent wave transmission allow the composite material to maintain a certain strength while possessing excellent cold resistance and a reasonable weight distribution. In terms of mechanical properties, it has high tensile strength and impact strength, effectively improving the compressive strength of the composite material under stress. When used synergistically with polyphenylene sulfide resin, the addition of high-density polystyrene resin can improve the toughness and cold resistance of the composite material, compensating for the shortcomings of polyphenylene sulfide resin in cold resistance and toughness under certain conditions. Simultaneously, the two interact during processing, helping to optimize the processing flow of the material, making the composite material easier to mold during preparation, thereby obtaining a more uniform and stable product.

[0010] Furthermore, the low-dielectric glass fiber described in this invention has a length of 200-220 μm, a dielectric constant of 2, and is tested at 1 GHz. Low-dielectric glass fiber plays a crucial role in improving the wave transmission performance of composite materials. Wave transmission performance is essential for composite materials used in specific fields, and the low dielectric constant of low-dielectric glass fiber is key to achieving this performance. Its dielectric constant is typically in a low range, effectively reducing electromagnetic wave loss within the material and allowing electromagnetic waves to penetrate the material better. In addition, low-dielectric glass fiber possesses high strength, providing reinforcement to composite materials and improving their mechanical properties.

[0011] Furthermore, the compatibilizer described in this invention is an ethylene-acrylate-glycidyl methacrylate copolymer. The function of the compatibilizer is to improve the interfacial compatibility between different components. In this invention, the ethylene-acrylate-glycidyl methacrylate copolymer compatibilizer reduces interfacial tension and enhances interfacial adhesion by undergoing chemical reactions or physical entanglement at the interfaces of different components such as polyphenylene sulfide resin and high-density polystyrene resin, thereby enabling more uniform mixing of the components and improving the overall performance of the composite material.

[0012] Furthermore, the preparation method of the low-dielectric filler of the present invention is as follows:

[0013] (1) Dissolve hafnium oxychloride octahydrate and gadolinium nitrate hexahydrate in a mixed solvent composed of anhydrous ethanol, ethylene glycol monoether and distilled water, and stir at 85°C for 2-3 hours to obtain a mixed sol. Add alumina dried at 100°C for 1 hour to the mixed sol and stir at room temperature for 3-4 hours to obtain a mixed solution.

[0014] (2) Centrifuge the mixture obtained in step (1) for 15-20 min to obtain a solid. Dry the solid at 80℃ for 10-12 h and then transfer it to a resistance furnace. Calcinate it at 400℃ for 2-3 h to obtain a low-dielectric filler. The low-dielectric filler is mainly used to adjust the dielectric properties of materials. It has a low dielectric constant and a particle size in the micrometer range. It can fill the voids in the matrix material, change the microstructure of the material, and thus adjust the dielectric constant. This has a positive impact on the wave transmission performance of the material and effectively reduces electromagnetic wave loss.

[0015] Furthermore, in the preparation method of the low dielectric filler of the present invention, the particle size of alumina is 800 mesh, and the ratio of hafnium oxychloride octahydrate, gadolinium nitrate hexahydrate, anhydrous ethanol, ethylene glycol monoether, distilled water, and alumina is 3g:1.6g:100mL:90mL:(120-150mL):2g; the centrifugation speed is 1000rpm, and the heating rate of the resistance furnace is 20℃ / min.

[0016] Furthermore, the lubricant described in this invention is silicone powder. During processing, the silicone powder lubricant reduces friction, improves flowability, and effectively protects components such as low-dielectric fillers from structural damage caused by the screw shearing of a twin-screw extruder. In composite material processing, the lubricant forms a lubricating film on the material surface, reducing friction between the material and the processing equipment, preventing material from sticking to the walls, improving material flowability, and making the extrusion process smoother, thus facilitating the production of composite material products with smooth surfaces and stable quality.

[0017] Furthermore, the compatibilizer described in this invention is nano-silica with a particle size of 50-80 nm. Nano-silica compatibilizer plays a crucial role in improving the overall performance of composite materials. Its principle is to enhance the compatibility and adhesion between components through interaction with different components. In this invention, the compatibilizer enables better bridging of components such as polyphenylene sulfide resin and high-density polystyrene resin, improving the overall mechanical properties, wave transmission properties, and thermal stability of the material, thus enabling the wave-transmitting polyphenylene sulfide composite material of this invention to exhibit superior comprehensive performance.

[0018] Furthermore, the antioxidant described in this invention is composed of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1. Antioxidants are crucial for improving the antioxidant properties of composite materials and extending their service life. Antioxidants 168 and 1010 can capture free radicals, terminate the oxidation chain reaction, and thus inhibit the oxidation process of the material. For example, at high temperatures, antioxidants 168 and 1010 can combine with active free radicals in the polyphenylene sulfide macromolecular chain, preventing them from further reacting with oxygen and effectively extending the service life of the composite material at high temperatures.

[0019] Another technical problem to be solved by the present invention is to provide a method for preparing the above-mentioned high and low temperature resistant, acid and alkali resistant, and radiation resistant translucent polyphenylene sulfide composite material.

[0020] To solve the above technical problems, the technical solution is as follows:

[0021] A method for preparing a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis, and radiation includes the following steps:

[0022] S1. Weigh each raw material according to the weight parts, and dry the polyphenylene sulfide resin and high-density polystyrene resin at 80-110℃ for 4-8 hours to obtain the pretreated resin.

[0023] S2. Add the low dielectric filler and compatibilizer to the mixer and mix at 800-1200 rpm and 85-95℃ for 8-10 minutes. Then add KH550 coupling agent to the mixer. The mass of KH550 coupling agent is 1% of the sum of the masses of the low dielectric filler and compatibilizer. Mix at 2500-3500 rpm and 110-115℃ for 2 minutes. Then adjust the speed to 800-1200 rpm and start the mixer cooling device to cool to 50℃ to obtain activated material.

[0024] S3. Add the pretreated resin obtained in step S1 to the mixer and mix at 350-500 rpm and 50-55°C for 2-3 minutes. Then add the compatibilizer, lubricant, and antioxidant to the mixer and mix at 350-500 rpm and 50-55°C for 5 minutes. Then add the activated material obtained in step S2 to the mixer and mix at 350-500 rpm and 50-55°C for 5 minutes to obtain the mixture.

[0025] S4. The mixture obtained in step S3 is fed into a twin-screw extruder, plasticized, sheared and mixed into the fifth side feed port of the twin-screw extruder, low dielectric glass fiber is added through the side feeder, and then plasticized, sheared, dispersed and mixed to obtain the extrudate. The extrudate is cooled, granulated and dried to obtain a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis and radiation. The twin-screw extruder has a length-to-diameter ratio of 40:1, a plasticizing temperature of 285-320℃, an extrusion pressure of 10-20MPa, a vacuum degassing pressure of -0.08MPa and a rotation speed of 200-300rpm. The drying temperature is 110-130℃ and the time is 2-4h.

[0026] Before preparing microwave-transparent polyphenylene sulfide (PPS) composite materials that are resistant to high and low temperatures, acids and alkalis, and radiation, pretreatment of raw materials such as PPS resin and high-density polystyrene resin is crucial. PPS resin typically requires drying to remove moisture, as the presence of moisture can lead to hydrolysis during processing, affecting its molecular structure and properties, such as reducing its mechanical properties and thermal stability. High-density polystyrene resin also requires drying at a similar temperature to PPS resin to remove the adverse effects of moisture on material processing and performance.

[0027] The plasticizing extrusion process of a twin-screw extruder is a crucial step in the preparation of composite materials. The temperature parameter setting range is 285-320℃, which is based on the melting temperature and processing characteristics of each raw material. Lower temperatures may result in insufficient melting and plasticization of the raw materials, affecting the mixing uniformity and flowability of the material; while excessively high temperatures may cause thermal degradation of the raw materials, damaging the material's structure and properties. For example, the melting point of polyphenylene sulfide resin is around 285℃, so it is necessary to ensure that the temperature reaches above its melting temperature to achieve good plasticization, but at the same time, it is necessary to avoid excessively high temperatures that could lead to degradation. To handle the gas generated during plasticization, the vacuum degassing pressure of the twin-screw extruder should be ≤-0.08MPa.

[0028] Pressure parameters are equally important in the extrusion process. A suitable pressure range helps the material to be fully mixed and plasticized in the extruder. Generally, the pressure is controlled at 10-20 MPa. Too low a pressure may cause uneven mixing of the material and make it impossible to form a uniform and stable melt. Too high a pressure may increase the energy consumption and wear of the equipment.

[0029] Regarding the rotation speed, the rotation speed of the twin-screw extruder should be set at 200-300 r / min. If the rotation speed is too low, the material will stay in the extruder for too long, increasing the risk of thermal degradation; if the rotation speed is too high, the material may not be mixed sufficiently, and the product quality cannot be guaranteed.

[0030] The drying step after granulation aims to further remove moisture that may have been adsorbed during the cooling and granulation process of the composite material, preventing moisture from adversely affecting the material's properties during subsequent processing or use, such as reducing its electrical and mechanical properties. The drying temperature and time need to be determined based on the material's characteristics and moisture content. Generally, the drying temperature is controlled at 110-130℃, and the drying time is 2-4 hours.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1) This invention selects a variety of raw materials such as polyphenylene sulfide resin, high-density polystyrene resin, and low-dielectric glass fiber, and reasonably combines compatibilizers, low-dielectric fillers, lubricants, compatibilizers and antioxidants, etc. The material cost is significantly reduced compared with the current market modified polyether ether ketone composite materials, modified polyphenylene sulfide / quartz fiber / polyimide systems and other wave-transparent materials.

[0033] 2) This invention utilizes coupling agents to activate low dielectric fillers and compatibilizers through appropriate temperature and time, thereby achieving synergistic effects among the components, improving the compatibility among the components, and further improving the various properties of the microwave-transparent polyphenylene sulfide composite material.

[0034] 3) Compared to the production of modified polyether ether ketone composite materials and modified polyphenylene sulfide / quartz fiber / polyimide systems currently on the market (which require special high-temperature resistant equipment, high energy consumption due to processing temperatures of 367-400℃, and complex and dangerous production processes), this invention only requires a conventional twin-screw extruder. By precisely controlling the plasticizing extrusion process of the twin-screw extruder and reasonably setting key process parameters such as temperature, pressure, and speed, the product quality can be effectively ensured to be stable.

[0035] 4) The low dielectric filler used in this invention is composed of hafnium oxychloride octahydrate, gadolinium nitrate hexahydrate, and alumina through sol-gel and calcination to combine hafnium oxide, gadolinium oxide, and alumina. Hafnium oxide has good radiation resistance, while gadolinium oxide has good dielectric properties, thus further improving the radiation resistance and wave transmission performance of the microwave-transparent polyphenylene sulfide composite material.

[0036] 5) This invention simultaneously possesses excellent high and low temperature resistance, acid and alkali resistance, radiation resistance, and wave transmission performance. Its overall performance is significantly superior to currently available wave-transparent composite materials, meeting the stringent requirements for material performance in special environments. It has broad application prospects in radar communication fields such as aerospace, chemical engineering, autonomous driving, 5G, and 6G communications. In the aerospace, autonomous driving, 5G, and 6G communication fields, this invention can be used to manufacture components such as satellite radomes and radar domes. Its wave transmission performance helps improve communication and detection accuracy, while its resistance to high and low temperatures, acids and alkalis, and radiation adapts to the complex environment of space. In the chemical industry, this invention can be used to manufacture sensor housings and pipeline inspection and communication systems operating in harsh environments. Its resistance to acid and alkali corrosion ensures long-term stable operation of equipment. Detailed Implementation

[0037] The present invention will now be described in detail with reference to specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.

[0038] Example 1

[0039] A microwave-transparent polyphenylene sulfide (PPS) composite material, resistant to high and low temperatures, acids and alkalis, and radiation, is made from the following raw materials in parts by weight: 40 parts PPS resin, 10 parts high-density polystyrene resin, 25 parts low-dielectric glass fiber, 3 parts compatibilizer, 15 parts low-dielectric filler, 1 part lubricant, 5 parts compatibilizer, and 1 part antioxidant. The PPS resin has a melt flow rate of 1000-1500 g / 10 min, tested at 316℃ and 5 kg; the high-density polystyrene resin has a density of 1.05-1.10 g / cm³. 3 The low-dielectric glass fiber has a length of 200-220 μm, a dielectric constant of 2, and is tested at 1 GHz. The compatibilizer is an ethylene-acrylate-glycidyl methacrylate copolymer. The lubricant is silicone powder. The compatibilizer is nano-silica with a particle size of 50-80 nm. The antioxidant consists of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1.

[0040] The preparation method of low dielectric filler is as follows:

[0041] (1) Hafnium oxychloride octahydrate and gadolinium nitrate hexahydrate were dissolved in a mixed solvent composed of anhydrous ethanol, ethylene glycol monoether and distilled water. The mixture was stirred at 85°C for 2 hours to obtain a mixed sol. Alumina with a particle size of 800 mesh was dried at 100°C for 1 hour and then added to the mixed sol. The mixture was stirred at room temperature for 3 hours to obtain a mixed solution. The ratio of hafnium oxychloride octahydrate, gadolinium nitrate hexahydrate, anhydrous ethanol, ethylene glycol monoether, distilled water and alumina was 3g:1.6g:100mL:90mL:120mL:2g.

[0042] (2) Centrifuge the mixture obtained in step (1) at 1000 rpm for 15 min to obtain a solid. Dry the solid at 80°C for 10 h and then transfer it to a resistance furnace. Heat it to 400°C at a heating rate of 20°C / min and calcine it for 2 h to obtain a low dielectric filler.

[0043] The preparation method of Example 1 includes the following steps:

[0044] S1. Weigh each raw material according to the weight parts, and dry the polyphenylene sulfide resin and high-density polystyrene resin at 80°C for 8 hours to obtain the pretreated resin.

[0045] S2. Add the low dielectric filler and compatibilizer to the mixer and mix at 1200 rpm and 85°C for 8 minutes. Then add KH550 coupling agent to the mixer. The mass of KH550 coupling agent is 1% of the sum of the masses of the low dielectric filler and compatibilizer. Mix at 3500 rpm and 110°C for 2 minutes. Then adjust the speed to 1200 rpm and start the mixer cooling device to cool to 50°C to obtain activated material.

[0046] S3. Add the pretreated resin obtained in step S1 to the mixer and mix at 500 rpm and 50°C for 3 minutes. Then add the compatibilizer, lubricant, and antioxidant to the mixer and mix at 500 rpm and 50°C for 5 minutes. Then add the activated material obtained in step S2 to the mixer and mix at 500 rpm and 50°C for 5 minutes to obtain the mixture.

[0047] S4. The mixture obtained in step S3 is fed into a twin-screw extruder, plasticized, sheared and mixed into the fifth side feed port of the twin-screw extruder, low dielectric glass fiber is added through the side feeder, and then plasticized, sheared, dispersed and mixed to obtain the extrudate. The extrudate is cooled, granulated and dried to obtain a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis and radiation. The twin-screw extruder has an aspect ratio of 40:1, a plasticizing temperature of 285℃, an extrusion pressure of 20MPa, a vacuum degassing pressure of -0.08MPa and a rotation speed of 300rpm. The drying temperature is 110℃ and the time is 4h.

[0048] Example 2

[0049] A microwave-transparent polyphenylene sulfide (PPS) composite material, resistant to high and low temperatures, acids and alkalis, and radiation, is made from the following raw materials in parts by weight: 55 parts PPS resin, 15 parts high-density polystyrene resin, 35 parts low-dielectric glass fiber, 5 parts compatibilizer, 10 parts low-dielectric filler, 3 parts lubricant, 3 parts compatibilizer, and 2 parts antioxidant. The PPS resin has a melt flow rate of 1000-1500 g / 10 min, tested at 316℃ and 5 kg; the high-density polystyrene resin has a density of 1.05-1.10 g / cm³. 3 The low-dielectric glass fiber has a length of 200-220 μm, a dielectric constant of 2, and is tested at 1 GHz. The compatibilizer is an ethylene-acrylate-glycidyl methacrylate copolymer. The lubricant is silicone powder. The compatibilizer is nano-silica with a particle size of 50-80 nm. The antioxidant consists of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1.

[0050] The preparation method of low dielectric filler is as follows:

[0051] (1) Hafnium oxychloride octahydrate and gadolinium nitrate hexahydrate were dissolved in a mixed solvent composed of anhydrous ethanol, ethylene glycol monoether and distilled water. The mixture was stirred at 85°C for 2.5 h to obtain a mixed sol. Alumina with a particle size of 800 mesh was dried at 100°C for 1 h and then added to the mixed sol. The mixture was stirred at room temperature for 3.5 h to obtain a mixed solution. The ratio of hafnium oxychloride octahydrate, gadolinium nitrate hexahydrate, anhydrous ethanol, ethylene glycol monoether, distilled water and alumina was 3 g: 1.6 g: 100 mL: 90 mL: 135 mL: 2 g.

[0052] (2) Centrifuge the mixture obtained in step (1) at 1000 rpm for 18 min to obtain a solid. Dry the solid at 80°C for 11 h and then transfer it to a resistance furnace. Heat it to 400°C at a heating rate of 20°C / min and calcine it for 2.5 h to obtain a low dielectric filler.

[0053] The preparation method of Example 2 includes the following steps:

[0054] S1. Weigh each raw material according to the weight parts, and dry the polyphenylene sulfide resin and high-density polystyrene resin at 100℃ for 6 hours to obtain the pretreated resin.

[0055] S2. Add the low dielectric filler and compatibilizer to the mixer and mix at 1000 rpm and 90°C for 9 minutes. Then add the KH550 coupling agent to the mixer. The mass of the KH550 coupling agent is 1% of the sum of the masses of the low dielectric filler and compatibilizer. Mix at 3000 rpm and 112°C for 2 minutes. Then adjust the speed to 1000 rpm and start the mixer cooling device to cool to 50°C to obtain the activated material.

[0056] S3. Add the pretreated resin obtained in step S1 to the mixer and mix at 400 rpm and 52°C for 2.5 min. Then add the compatibilizer, lubricant, and antioxidant to the mixer and mix at 400 rpm and 52°C for 5 min. Then add the activated material obtained in step S2 to the mixer and mix at 400 rpm and 52°C for 5 min to obtain the mixture.

[0057] S4. The mixture obtained in step S3 is fed into a twin-screw extruder, plasticized, sheared by the screw block, and kneaded to the fifth side feed port of the twin-screw extruder. Low-dielectric glass fiber is added through the side feeder, and then plasticized, sheared by the screw block, dispersed, and kneaded to obtain the extrudate. The extrudate is cooled, granulated, and dried to obtain a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis, and radiation. The twin-screw extruder has a length-to-diameter ratio of 40:1, a plasticizing temperature of 300℃, an extrusion pressure of 15MPa, a vacuum degassing pressure of -0.08MPa, and a rotation speed of 250rpm. The drying temperature is 120℃ and the drying time is 3h.

[0058] Example 3

[0059] A microwave-transparent polyphenylene sulfide (PPS) composite material, resistant to high and low temperatures, acids and alkalis, and radiation, is made from the following raw materials in parts by weight: 65 parts PPS resin, 25 parts high-density polystyrene resin, 15 parts low-dielectric glass fiber, 8 parts compatibilizer, 25 parts low-dielectric filler, 2 parts lubricant, 6 parts compatibilizer, and 1.5 parts antioxidant. The PPS resin has a melt flow rate of 1000-1500 g / 10 min, tested at 316℃ and 5 kg; the high-density polystyrene resin has a density of 1.05-1.10 g / cm³. 3 The low-dielectric glass fiber has a length of 200-220 μm, a dielectric constant of 2, and is tested at 1 GHz. The compatibilizer is an ethylene-acrylate-glycidyl methacrylate copolymer. The lubricant is silicone powder. The compatibilizer is nano-silica with a particle size of 50-80 nm. The antioxidant consists of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:1.

[0060] The preparation method of low dielectric filler is as follows:

[0061] (1) Hafnium oxychloride octahydrate and gadolinium nitrate hexahydrate were dissolved in a mixed solvent composed of anhydrous ethanol, ethylene glycol monoether and distilled water. The mixture was stirred at 85°C for 3 hours to obtain a mixed sol. Alumina with a particle size of 800 mesh was dried at 100°C for 1 hour and then added to the mixed sol. The mixture was stirred at room temperature for 4 hours to obtain a mixed solution. The ratio of hafnium oxychloride octahydrate, gadolinium nitrate hexahydrate, anhydrous ethanol, ethylene glycol monoether, distilled water and alumina was 3g:1.6g:100mL:90mL:150mL:2g.

[0062] (2) Centrifuge the mixture obtained in step (1) at 1000 rpm for 20 min to obtain a solid. Dry the solid at 80°C for 12 h and then transfer it to a resistance furnace. Heat it to 400°C at a heating rate of 20°C / min and calcine it for 3 h to obtain a low dielectric filler.

[0063] The preparation method of Example 3 includes the following steps:

[0064] S1. Weigh each raw material according to the weight parts, and dry the polyphenylene sulfide resin and high-density polystyrene resin at 110℃ for 4 hours to obtain the pretreated resin.

[0065] S2. Add the low dielectric filler and compatibilizer to the mixer and mix at 800 rpm and 95°C for 10 minutes. Then add the KH550 coupling agent to the mixer. The mass of the KH550 coupling agent is 1% of the sum of the masses of the low dielectric filler and compatibilizer. Mix at 2500 rpm and 115°C for 2 minutes. Then adjust the speed to 800 rpm and start the mixer cooling device to cool to 50°C to obtain the activated material.

[0066] S3. Add the pretreated resin obtained in step S1 to the mixer and mix at 350 rpm and 55°C for 2 minutes. Then add the compatibilizer, lubricant, and antioxidant to the mixer and mix at 350 rpm and 55°C for 5 minutes. Then add the activated material obtained in step S2 to the mixer and mix at 350 rpm and 55°C for 5 minutes to obtain the mixture.

[0067] S4. The mixture obtained in step S3 is fed into a twin-screw extruder, plasticized, sheared by the screw block, and kneaded to the fifth side feed port of the twin-screw extruder. Low-dielectric glass fiber is added through the side feeder, and then plasticized, sheared by the screw block, dispersed, and kneaded to obtain the extrudate. The extrudate is cooled, granulated, and dried to obtain a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis, and radiation. The twin-screw extruder has an aspect ratio of 40:1, a plasticizing temperature of 320℃, an extrusion pressure of 10MPa, a vacuum degassing pressure of -0.08MPa, and a rotation speed of 200rpm. The drying temperature is 130℃ and the drying time is 2h.

[0068] Comparative Example 1

[0069] The difference from Example 1 is that the polyphenylene sulfide resin in the raw materials is replaced with PEEK resin, and the plasticizing temperature in step S4 of the preparation method is increased to 350°C.

[0070] Comparative Example 2

[0071] The difference from Example 1 is that hafnium oxychloride octahydrate was not used in the preparation method of the low dielectric filler in the raw materials, that is, the low dielectric filler does not contain hafnium oxide.

[0072] Comparative Example 3

[0073] The difference from Example 1 is that gadolinium nitrate hexahydrate was not used in the preparation method of the low dielectric filler in the raw materials, that is, the low dielectric filler does not contain gadolinium oxide.

[0074] Test Example 1: High and Low Temperature Resistance Test

[0075] The notched impact strength of the test samples (composite materials prepared in Examples 1-3 and Comparative Examples 1-3) was measured according to GB / T 1043.1-2008 and denoted as notched impact strength A. Then, the test samples (composite materials prepared in Examples 1-3 and Comparative Example 1) were placed in a high and low temperature alternating test chamber, and different temperature cycling programs were set to simulate extreme temperature environments. In the low-temperature stage, the temperature was set to -80℃ and maintained for 12 hours, followed by raising the temperature to 220℃ and maintaining it for 12 hours. This cycle was repeated 10 times, and the notched impact strength was measured again and denoted as notched impact strength B. The notched impact strength retention rate 1 was calculated according to the following formula:

[0076] Notched impact strength retention rate 1 = Notched impact strength B ÷ Notched impact strength A × 100%

[0077] A higher notched impact strength retention rate indicates better high and low temperature resistance. The test results are shown in Table 1.

[0078]

[0079]

[0080] Table 1

[0081] As can be seen from Table 1, the notched impact strength retention rate 1 of Examples 1-3 of the present invention is higher than that of Comparative Example 1, indicating that the microwave-transparent polyphenylene sulfide composite material prepared by the present invention has better high and low temperature resistance.

[0082] Test Example 2: Acid and Alkali Resistance Test

[0083] The test samples (composite materials prepared in Examples 1-3 and Comparative Example 1) were immersed in 5% sulfuric acid for 72 hours, then rinsed with deionized water and dried. They were then immersed in 10% sodium hydroxide solution for 72 hours, rinsed with deionized water and dried. The notched impact strength was then measured and recorded as notched impact strength C. The notched impact strength retention rate 2 was calculated according to the following formula, where the notched impact strength A was obtained from Test Example 1:

[0084] Notched impact strength retention rate 2 = Notched impact strength C ÷ Notched impact strength A × 100%

[0085] A higher notched impact strength retention rate (2%) indicates better acid and alkali resistance. The test results are shown in Table 2.

[0086] sample Notched impact strength retention rate 2 (%) Example 1 93.18 Example 2 93.63 Example 3 93.96 Comparative Example 1 81.21

[0087] Table 2

[0088] As can be seen from Table 2, the notched impact strength retention rate 2 of Examples 1-3 of the present invention is higher than that of Comparative Example 1, indicating that the microwave-transparent polyphenylene sulfide composite material prepared by the present invention has better acid and alkali resistance.

[0089] Test Example 3: Radiation Resistance Test

[0090] The test conditions were a gamma-ray radiation dose rate of 10 Gy / min and a total radiation dose of 500 Gy. The test samples (composite materials prepared in Examples 1-3 and Comparative Examples 1-2) were exposed to gamma-ray radiation. After reaching the total radiation dose, the samples were removed and their notched impact strength was measured, denoted as notched impact strength D. The notched impact strength retention rate 3 was calculated according to the following formula, where the notched impact strength A was obtained from Test Example 1:

[0091] Notched impact strength retention rate 3 = Notched impact strength C ÷ Notched impact strength A × 100%

[0092] A higher notched impact strength retention rate (3) indicates better radiation resistance. The test results are shown in Table 3.

[0093] sample Notched impact strength retention rate: 3% Example 1 93.96 Example 2 94.28 Example 3 94.33 Comparative Example 1 82.86 Comparative Example 2 85.79

[0094] Table 3

[0095] As shown in Table 3, the notched impact strength retention rate 3 of Examples 1-3 of the present invention is higher than that of Comparative Example 1, indicating that the microwave-transparent polyphenylene sulfide composite material prepared by the present invention has better radiation resistance. Compared with Example 1, the notched impact strength retention rate 3 of Comparative Example 2 is lower, indicating that the hafnium oxide in the low dielectric filler prepared by the present invention can effectively improve the radiation resistance of the microwave-transparent polyphenylene sulfide composite material.

[0096] Test Example 4: Wave Transmission Performance Test

[0097] Referring to GB / T 1409-2006, the test samples (composite materials prepared in Examples 1-3, Comparative Examples 1 and 3) were placed in the test fixture of the vector network analyzer. The test frequency was set to 10 GHz. The instrument emitted electromagnetic waves and received the electromagnetic wave signals transmitted or reflected by the test samples. After data processing and analysis, parameters such as the dielectric constant and dielectric loss tangent of the test samples were obtained.

[0098] A smaller dielectric constant and dielectric loss tangent indicate better wave transmission performance. The test results are shown in Table 4.

[0099] sample Dielectric constant Dielectric loss tangent Example 1 2.6 0.00085 Example 2 2.6 0.0009 Example 3 2.8 0.0007 Comparative Example 1 3.8 0.0014 Comparative Example 3 3.5 0.0010

[0100] Table 4

[0101] As shown in Table 4, the dielectric constant and dielectric loss tangent of Examples 1-4 of the present invention are all lower than those of Comparative Example 1, indicating that the microwave-transparent polyphenylene sulfide composite material prepared by the present invention has better microwave transmission performance. Compared with Example 1, the dielectric constant and dielectric loss tangent of Comparative Example 3 are both increased, indicating that gadolinium oxide in the low dielectric filler prepared by the present invention can effectively improve the microwave transmission performance of the microwave-transparent polyphenylene sulfide composite material.

[0102] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis, and radiation, characterized in that: It is made from the following raw materials in parts by weight: 40-65 parts of polyphenylene sulfide resin, 10-25 parts of high-density polystyrene resin, 15-35 parts of low-dielectric glass fiber, 3-8 parts of compatibilizer, 10-25 parts of low-dielectric filler, 1-3 parts of lubricant, 3-6 parts of compatibilizer, and 1-2 parts of antioxidant. The method for preparing the low-dielectric filler is as follows: (1) Dissolve hafnium oxychloride octahydrate and gadolinium nitrate hexahydrate in a mixed solvent consisting of anhydrous ethanol, ethylene glycol monoether and distilled water, and stir at 85°C for 2-3 hours to obtain a mixed sol. Add alumina dried at 100°C for 1 hour to the mixed sol and stir at room temperature for 3-4 hours to obtain a mixed solution. (2) Centrifuge the mixture obtained in step (1) for 15-20 min to obtain a solid. Dry the solid at 80°C for 10-12 h and then transfer it to a resistance furnace. Heat it to 400°C and calcine it for 2-3 h to obtain a low dielectric filler.

2. The microwave-transparent polyphenylene sulfide composite material resistant to high and low temperatures, acids and alkalis, and radiation as described in claim 1, characterized in that: The melt flow rate of the polyphenylene sulfide resin is 1000-1500 g / 10 min, and the test conditions are 316℃ and 5 kg; the density of the high-density polystyrene resin is 1.05-1.10 g / cm³.

3. The microwave-transparent polyphenylene sulfide composite material resistant to high and low temperatures, acids and alkalis, and radiation as described in claim 1, characterized in that: The low-dielectric glass fiber has a length of 200-220 μm, a dielectric constant of 2, and is tested at 1 GHz.

4. The microwave-transparent polyphenylene sulfide composite material resistant to high and low temperatures, acids and alkalis, and radiation as described in claim 1, characterized in that: The compatibilizer is an ethylene-acrylate-glycidyl methacrylate copolymer.

5. The microwave-transparent polyphenylene sulfide composite material resistant to high and low temperatures, acids and alkalis, and radiation as described in claim 1, characterized in that: In the preparation method of the low dielectric filler, the particle size of alumina is 800 mesh, and the ratio of hafnium oxychloride octahydrate, gadolinium nitrate hexahydrate, anhydrous ethanol, ethylene glycol monoether, distilled water and alumina is 3g:1.6g:100mL:90mL:(120-150mL):2g; the centrifugation speed is 1000rpm, and the heating rate of the resistance furnace is 20℃ / min.

6. The microwave-transparent polyphenylene sulfide composite material resistant to high and low temperatures, acids and alkalis, and radiation as described in claim 1, characterized in that: The lubricant is silicone powder.

7. The microwave-transparent polyphenylene sulfide composite material resistant to high and low temperatures, acids and alkalis, and radiation as described in claim 1, characterized in that: The compatibilizer is nano-silica with a particle size of 50-80 nm.

8. The microwave-transparent polyphenylene sulfide composite material resistant to high and low temperatures, acids and alkalis, and radiation as described in claim 1, characterized in that: The antioxidant is composed of antioxidant 168 and antioxidant 1010 in a mass ratio of 1:

1.

9. The method for preparing the high and low temperature resistant, acid and alkali resistant, and radiation-resistant microwave-transparent polyphenylene sulfide composite material according to any one of claims 1-8, characterized in that: Includes the following steps: S1. Weigh each raw material according to the weight parts, and dry the polyphenylene sulfide resin and high-density polystyrene resin at 80-110℃ for 4-8 hours to obtain the pretreated resin. S2. Add the low dielectric filler and compatibilizer to the mixer and mix at 800-1200 rpm and 85-95℃ for 8-10 minutes. Then add KH550 coupling agent to the mixer. The mass of KH550 coupling agent is 1% of the sum of the masses of the low dielectric filler and compatibilizer. Mix at 2500-3500 rpm and 110-115℃ for 2 minutes. Then adjust the speed to 800-1200 rpm and start the mixer cooling device to cool to 50℃ to obtain activated material. S3. Add the pretreated resin obtained in step S1 to the mixer and mix at 350-500 rpm and 50-55°C for 2-3 minutes. Then add the compatibilizer, lubricant, and antioxidant to the mixer and mix at 350-500 rpm and 50-55°C for 5 minutes. Then add the activated material obtained in step S2 to the mixer and mix at 350-500 rpm and 50-55°C for 5 minutes to obtain the mixture. S4. The mixture obtained in step S3 is fed into a twin-screw extruder, plasticized, sheared and mixed into the screw block, and fed into the fifth side feed port of the twin-screw extruder. Low dielectric glass fiber is added through the side feeder, and then plasticized, sheared, dispersed and mixed to obtain the extrudate. The extrudate is cooled, granulated and dried to obtain a microwave-transparent polyphenylene sulfide composite material that is resistant to high and low temperatures, acids and alkalis and radiation. The twin-screw extruder has a length-to-diameter ratio of 40:1, a plasticizing temperature of 285-320℃, an extrusion pressure of 10-20MPa, a vacuum degassing pressure of -0.08MPa and a rotation speed of 200-300rpm. The drying temperature is 110-130℃ and the time is 2-4h.

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