1.Special engineering plastics: products at the top of the plastic pyramid, with excellent performance and high added value
1.1.Special engineering plastics have excellent physical and chemical properties
Special engineering plastics have excellent performance and are products at the top of the plastic pyramid. Plastics can be roughly divided into three categories: general plastics, engineering plastics and special engineering plastics according to production scale, product performance and added value. General plastics include common plastics, ABS (Acrylonitrile butadiene styrene), polyethylene PE, polypropylene PP, etc., which are characterized by large production scale. However their performance is relatively low and their price is cheap. The production scale of special engineering plastics is smaller than that of general-purpose plastics, but because of its superior temperature resistance, light resistance and mechanical properties, it is the product at the top of the plastic pyramid.
Special engineering plastics are mainly divided into six categories: polyimide, polyphenylene sulfide, polysulfone, liquid crystal polymer, high temperature nylon and polyaryl ether ketone. They can be used in electronics, transportation, aerospace and other fields. Special engineering plastics are also known as high temperature resistant polymer materials in the early days. They have excellent high temperature resistance. Its long-term working temperature can be 150°C or above. In addition, the comprehensive performance of special engineering plastics is excellent.
Polyimide is stable. It has strong corrosion resistance, and low smoke generation rate. It will not break in liquid helium for a period of time. It is used in aerospace, electronic appliances, machinery, electronic display and other fields.
Polyphenylene sulfide has certain fluidity, fast crystallization, good heat resistance and excellent corrosion resistance. It is mainly used in automobiles, electronic appliances and other fields.
Polysulfone has the advantages of heat resistance and damp heat resistance. And it has excellent mechanical properties and processing properties. It is used in machinery industry, electronic appliances, transportation, medical equipment and other fields.
Liquid crystal polymers have excellent mechanical properties, low hygroscopicity, low dielectric constant and dielectric loss, good dimensional stability and other excellent properties. They are used in electronic appliances, defense and military industry, aerospace, automotive, medical and other fields.
High temperature resistant nylon has high temperature resistance and good mechanical properties, and is mainly used in electronic appliances, automobile industry and other fields.
Polyaryletherketone has excellent high temperature resistance, wear resistance, mechanical properties, dimensional stability, insulation and biocompatibility. It is widely used in automobiles, electronic appliances, aerospace, medical and health and other fields. In China, the import dependence of polyimide has been reduced to 25%, and polyphenylene sulfide has broken complete import dependence. And the rest of the import dependence is relatively high.
1.2. The added value of special engineering plastics is higher, and the localization process is accelerated
In terms of product added value, special engineering plastics, bigger than general engineering plastics, which is bigger than traditional general purpose plastics. Special engineering plastics are difficult to replace, so the price is higher.
Taking special engineering plastic liquid crystal polymer LCP, general engineering plastic polycarbonate PC and traditional general plastic polyethylene PE as examples, the prices of LCP, PC and PE are about RMB 55,000/ton, RMB 25,000/ton, and RMB 9,000. / ton. The price of special engineering plastics is significantly higher than the other two types of plastics. And it has a higher gross profit level.
The development of domestic special engineering plastics started late, but the localization process has accelerated in recent years.
- Special engineering plastics were developed in the 1960s, starting with the advent of polyimide. A variety of special engineering plastics have been developed in the following 20 years.
- In 1961, DuPont prepared polypyromellitic tetracarboximide film (Kapton) through the condensation reaction of aromatic diamine and aromatic dianhydride. It is used as engineering plastics.
- In 1965, Union Carbide Company developed polysulfone. And in the same year, a production line (Udel) with an annual output of 4,500 tons was built.
- In 1972, lyotropic liquid crystal Kevlar fiber was successfully developed.
- In 1967, Phillips Company obtained a patent for synthesizing polyphenylene sulfide in N-methylpyrrolidone solvent using p-dichlorobenzene and sodium sulfide as raw materials, which was realized in 1971. Industrial production, and built a 2,600-ton production line in 1973.
- In 1979, high molecular weight PEK was produced, and in 1977, PEEK was developed and put into production in 1980.
- The research on special engineering plastics in my country also started in the 1960s, but it did not develop until the 1980s.
There is still a certain gap between the overall and the international market, but China domestic companies have broken through Celanese, Poly, Sumitomo and Solvay in recent years. Monopolized by other overseas companies, the expansion of special engineering plastics is mainly concentrated in domestic leading companies such as Kingfa Technology, Water Shares, and Plitte.
The expansion rate of domestic enterprises exceeded market expectations, and the localization process accelerated. Kingfa Technology has its own patented high-temperature nylon PA 10T, which took 10 years to develop from scratch to 3,000 tons. The 2022 semi-annual report disclosed that the annual output will increase by 15,000 tons. The PES synthetic resin project has completed the process and civil engineering design. In 2021, Wote Co., Ltd. will start a project with an annual output of 20,000 tons of LCP and an annual output of 10,000 tons of high-performance new materials, of which the main equipment installation of the LCP project has been completed. The main enterprises in the industry continue to expand production, which confirms the explosive trend of the industry.
New application scenarios continue to emerge, and sales of special engineering plastics are expected to explode. Usually, the launch of new products often requires the joint guidance and promotion of relevant head modification companies. And it takes the lead by virtue of performance advantages. At present, we have witnessed emerging industries with rapid development of electric vehicles, photovoltaics, energy storage, and power exchange industries. And we also have seen the continuous iteration of new application scenarios, such as the introduction of new models of electric vehicles at a higher frequency. This gives special engineering plastics continuous testing and strengthening of application value. At present, special engineering plastics have shown a certain cost-effectiveness advantage. We judge that with the large-scale increase of domestic production capacity, the price center moves down, and the cost-effectiveness is further highlighted. The explosion of sales is an inevitable trend.
2. The rapid development of downstream high-tech industries drives the demand for special engineering plastics
2.1. Liquid crystal polymer: The 5G field is widely used, and domestic substitution is accelerating
2.1.1. LCP has excellent high temperature resistance and dielectric properties, and is mainly synthesized by acid hydrolysis
Liquid crystal polymers (LCPs) are widely used in electronics due to their excellent high temperature resistance and dielectric properties. Liquid Crystal Polyester (LCP, Liquid Crystal Polyester) is composed of rigid molecular chains and has a certain (one-dimensional or two-dimensional) order. Anisotropic, aromatic polyester materials with a large number of rigid benzene ring structures on the main chain.
LCP can be divided into three types: lyotropic liquid crystal (LLCP), thermotropic liquid crystal (TLCP) and piezotropic liquid crystal. LLCP is in liquid crystal state in solvent. It can only be processed in solution, cannot be melted, and can be used as fibers and coatings. TLCP is in liquid crystal state due to temperature changes. It has excellent comprehensive properties, and can be processed by injection molding and extrusion. According to heat distortion temperature (HDT), TLCP can also be subdivided into high heat resistance type (HDT≥300℃), medium heat resistance type (280℃≥HDT≥240℃) and low heat resistance type (HDT≤210℃) . LCP has excellent mechanical properties, and also has the characteristics of low moisture absorption, weather resistance, heat resistance, flame retardancy, low dielectric constant and dielectric loss factor, etc. It is widely used in the field of electronics.
Acid hydrolysis is the mainstream LCP industrial production method. At present, there are four main synthesis methods of LCP, namely oxidative esterification method, silicon ester method, phenyl ester method and acid hydrolysis reaction method. Among them, acid hydrolysis reaction method is the most important method for industrial production of LCP. The acid hydrolysis method is to melt polycondensation of aromatic dibasic acids and acetylated phenolic monomers, remove the by-product acetic acid to obtain LCP, and then obtain LCP through processing methods such as injection molding, extrusion, solution casting, blow molding and film drawing. Through this methods, we get various forms of LCP products.
2.1.2. The global LCP production capacity is concentrated in the United States and Japan, and the domestic LCP production capacity is developing rapidly
The global LCP production capacity is mainly concentrated in Japan and the United States. However, China domestic LCP production capacity is growing rapidly. The current global LCP material production capacity is about 82,000 tons, mainly concentrated in Japan and the United States, with a high industry concentration. Celanese in the United States ranks first in the world with a production capacity of 22,000 tons. It is followed by Poly and Sumitomo of Japan, with production capacities of 15,000 tons and 10,000 tons respectively. The development of domestic LCP started late, with a total production capacity of about 16,000 tons. In recent years, with the rapid development of companies such as Kingfa Technology, Plitte, and Water, the domestic production capacity has grown rapidly. Among them, Water is expected to put into production 15,000 tons and 5,000 tons of LCP respectively in 2022-2023. It is expected to become the world’s largest supplier of LCP materials.
2.1.3. The rapid development of 5G drives the demand for liquid crystal polymers
In the future, the demand for LCP in China is expected to continue to grow. In 2020, the global LCP demand is 78,000 tons, and the domestic LCP demand is 32,000 tons. Electronic appliances are the most important consumer areas of LCP. With the rapid development of the electrical and electronic industry, the demand for LCP in China is expected to continue to grow in the future. According to China Chemical Information Center, total domestic LCP consumption will increase from 32,000 tons to 43,000 tons by 2026.
LCP is lightweight, resistant to high temperature and low in dielectric loss factor. It can be used as a plastic vibrator material for 5G base station antennas. The antenna element in the base station is the main component of the antenna, which can amplify the signal and control the signal radiation direction.
5G base stations have strict requirements for vibrator materials:
(1)the manufacturing process of surface mount technology (SMT) requires that the vibrator material can withstand 260 °C;
(2)lightweight;
the higher the frequency of electromagnetic waves, the shorter the wavelength, the more It is easy to attenuate in the propagation medium. Therefore the higher the frequency, the smaller the loss of the oscillator material is required.
Compared with traditional metal vibrators, plastic vibrators are not only lightweight, but also can achieve high precision through injection molding. This is the direction of 5G antenna vibrators. Compared with the current mainstream polyphenylene sulfide (PPS) plastic vibrators, LCP plastic vibrators have better injection properties, heat resistance and lower dielectric loss, It have greater competitive advantages.
It is estimated that by 2025, the new demand for 5G base station oscillators corresponding to LCP will be 10,700 tons. As of June 2022, the number of 5G base stations that have been built in China has reached 1.854 million, accounting for more than 60% of the world. According to the “14th Five-Year Plan for Information and Communication Industry Development” issued by the Ministry of Industry and Information Technology, it is planned to achieve 26 5G base stations per 10,000 people by 2025. According to this, it is estimated that by 2025, the total number of 5G base stations in China will reach 3.64 million. Usually 5G base stations have 3 antennas. Assuming that the mainstream solution of single-sided antenna uses 192 oscillators, correspondingly, one base station needs 576 oscillators. The density of LCP and PPS is close, and 96 oscillators need about 1kg of PPS in total. It is estimated that by 2025, the new demand for LCP vibrator materials will be 10,700 tons.
LCP materials have excellent dielectric properties and flexibility. It can replace traditional polyimide materials in 5G flexible printed circuit boards. LCP materials can be used as substrates in 5G high-frequency high-speed circuit boards, especially flexible printed circuit boards (FPC). The traditional circuit board substrate polyimide (PI) substrate has high dielectric constant and loss factor and high moisture absorption. Therefore it has serious loss during high-frequency transmission and cannot adapt to the current high-frequency and high-speed trend. Compared with PI, LCP material has a significant advantage in transmission loss, and the substrate loss value is only 0.2%-0.4%, which is only 1/10 of the traditional substrate. Moreover, the high mechanical strength of LCP can support the structure of multi-layer wiring. The bendability also caters to the miniaturization trend. LCP-based circuit boards are mostly used in 5G mobile phone antennas and notebook computers.
LCP can be used as a highly stable, small and precise 5G connector. Connectors serve as bridges between circuits or other components and serve as electrical or signal connections. 5G connectors are mostly used in base station antennas, BBU equipment and 5G mobile phones (FPC connectors). The transmission speed of 5G has been greatly improved, and the connector needs to have lower low dielectric and low loss. The use frequency of the connector is extremely high, and the material needs to have good dimensional stability. During the use of the connector, the current will generate heat at the contact point, resulting in a temperature rise, requiring the material to have better high temperature resistance.
LCP material has low dielectric loss, good dimensional stability and high temperature resistance, suitable for 5G high-speed connectors. The construction of 5G base stations and the increase in shipments of 5G mobile phones have driven the demand for high-performance 5G connectors. According to the current mainstream architecture of 5G communication base stations, each base station will use 64 RF connectors, and each macro base station needs to use 192 sets (with dielectric filter structure) or 384 sets (with metal filter structure) board-to-board connectors. The thinness and multi-function of 5G mobile phones also require high internal integration of mobile phones, and higher requirements for mobile phone connectors.
LCPs also have applications in robotic connectors and servo motors. With the launch of Xiaomi CyberOne and the upcoming release of Tesla Optimus, the development of humanoid robots has gradually increased. In the future, robots will have higher and higher requirements for weight and size. Integration is very important. There will be more applications for connectors, which is expected to bring explosive growth in demand. Connectors in robots require materials with bendability, low dielectric loss, high temperature resistance, and good dimensional and chemical stability. LCP is an important material for robotic connectors. The LCP is also included in the servo motor, the core component of the humanoid robot. Servo motors are generally installed at the joints of the robot. It is estimated that a single humanoid robot will use more than 40 servo motors. The skeleton material inside is required to be lightweight, easy to process, have good insulation and can withstand motor heat. LCP can better meet the material requirements . Due to the large output of humanoid robots in the future, it is expected to reach the output of one million units by 2025. If the LCP consumption of a single robot is 1kg, the corresponding LCP per million robots is 1,000 tons.
2.1.4. China domestic substitution of LCP is expected to be realized in the future, and LCP prices will rise due to supply and demand
At present, China’s LCP is highly dependent on foreign countries, and domestic substitution is expected to accelerate. In 2020, the domestic demand for LCP is 32,000 tons, while the domestic annual production capacity is only 16,000 tons. According to “China Chemical Industry Information Weekly”, due to the influence of technology and product quality, the actual import dependence of LCP in China is 80%. The domestic demand for LCP is expected to be 43,000 tons in 2026. With the implementation of LCP production facilities and technological progress, domestic manufacturers such as Wote Co., Ltd. and Kingfa Technology have successively increased their layout efforts. Among them, Wote Co., Ltd. is expected to put into production 15,000 tons and 5,000 tons of LCP respectively in 2022-2023. Kingfa Technology has launched the LCP project with an annual output of 15,000 tons. Civil engineering design has been completed. The process of domestic substitution of LCP is accelerated.
2.3. High-temperature nylon: excellent temperature resistance, replacing steel with plastic in line with the trend of lightweight automobiles
2.3.1. Excellent mechanical properties and high temperature resistance of high temperature nylon
High temperature nylon is widely used in electronics and automotive fields because of its excellent mechanical properties and high temperature resistance. Nylon (polyamide, PA) is a general term for polymers whose repeating units in the main chain contain amide groups (-CONH-). High-temperature nylon is a PA with a long-term use temperature above 150 °C, and is mainly divided into semi-aromatic nylon and full-aromatic nylon. Fully aromatic nylon has a high melting point, which is not conducive to processing; semi-aromatic nylon can take into account good heat resistance and processing performance. Common high temperature nylons are PPA, PA4T, PA6T, PA9T and PA10T. High temperature resistant nylon not only has good mechanical, creep resistance, flame retardant and high temperature resistance properties, but also is lighter than metal, so it is used in the automotive field as parts and pipes in the engine area. The excellent plasticity, high strength and low warpage of high temperature nylon also make it suitable for applications in the electronic field, as connectors, etc. Electronics and automobiles are the most important consumer markets for high-temperature nylon, which together account for more than 85% of the total consumption. Electronics and transportation will account for 58% and 30% of high-temperature nylon consumption, respectively, in 2020.
High temperature and high pressure solution polycondensation method is the mainstream industrial production method of high temperature resistant nylon. At present, there are five main synthesis methods of high temperature nylon, namely high temperature and high pressure solution polycondensation method, low temperature solution polycondensation method, polyester polycondensation method, interfacial polymerization method and direct melt polycondensation method. The high temperature and high pressure solution polycondensation process is under the protection of N2 atmosphere, the same amount of dibasic acid and dibasic amine, an appropriate amount of water and a small amount of reactants are in a high pressure polymerization reactor to synthesize nylon salt at a low temperature, and then heat up the prepolymer. A low molecular weight prepolymer is obtained. After the prepolymer is vacuum-dried, the final product with high melting point and high molecular weight is obtained by solid-phase polycondensation or melt polymerization. This reaction is an aqueous reaction system, and the production cost is low. After years of development, the process has been quite mature and has been successfully applied in industrial production.
2.3.2. The domestic high temperature nylon is highly dependent on imports, and the domestic high temperature nylon accelerates the layout
High-temperature nylon production enterprises are mainly overseas, and there is still a gap between domestic high-temperature nylon enterprises and overseas. In 2020, the global high-temperature nylon production capacity will be 264,000 tons. The main producers are DuPont, DSM, Emmans, Solvay, BASF, and Japan’s Mitsui Chemicals and Kuraray. The domestic production capacity is about 16,500 tons/year. The domestic high-temperature nylon enterprises started late, the number is still small, the production scale is small, the category is relatively single, and the product performance stability is insufficient.
2.3.3. High temperature nylon is mainly used in electronics and automotive fields
Electronics and automotive are the most important consumer markets for high temperature nylon. At present, the consumption of high-temperature nylon products is mainly concentrated in the fields of electronics, automobiles, consumer goods, aerospace and military industries, among which electronics and automobiles account for more than 85% of the total consumption of high-temperature nylon. Electronics and transportation will account for 58% and 30% of high-temperature nylon consumption, respectively, in 2020.
High temperature nylon withstands high temperatures in LDS and SMT processing and is used in miniaturized electronics. High temperature nylon has excellent high temperature resistance, mechanical properties, dimensional stability and dielectric properties, and is also used in the field of electronics. Compared with LCP, the high temperature nylon bond wire has higher strength and better leakage resistance, is safer, and has higher mechanical strength. High temperature nylon can use laser direct structuring technology (LDS) and surface mount technology (SMT), and has good processability.
Under the trend of lightweight automobiles, high-temperature nylon can replace metal materials and be used in multiple systems of traditional fuel vehicles. In the automotive field, traditional fuel vehicles can effectively improve fuel efficiency, reduce carbon emissions and fuel consumption by increasing the combustion temperature of the vehicle engine. Therefore, the requirements for heat resistance of engine parts are constantly increasing, and high-temperature nylon can meet relevant engine application requirements.
Moreover, under the trend of lightweight automobiles, high-temperature nylon can replace metal materials and be used in engines (decorative covers, fixed brackets), suction systems (suction ducts, buffer tanks, throttle bodies, intake manifolds), In cooling system (water chamber, bracket, water pipe, fan), oil circuit valve system (oil pan, timing pulley cover, chain guide groove) and fuel system (fuel pipe).
High temperature nylon is used in battery systems and pipelines of new energy vehicles. The new energy vehicle also adopts a lightweight design idea, using polymer materials to replace the original metal parts, requiring the materials to have good dielectric properties, thermal properties, mechanical properties and flame retardancy. And high-temperature nylon materials can be used in AC Motor housings, charger modules, battery boxes and electronic controllers, battery systems for electric vehicles. High-temperature nylon has a broad market prospect in new energy vehicle pipelines. The average cooling pipeline of a hybrid vehicle is 13.5 meters, and that of a pure electric vehicle is 16 meters, both higher than the 5.5 meters of a traditional fuel vehicle. High temperature nylon can also be used to manufacture body, chassis, etc. after being reinforced with carbon fiber. Kingfa Technology and Plitter also have 2 patents in the past five years mentioning the use of high temperature resistant nylon in automotive structures. According to Walter, BAIC Polar Fox and other models have begun to use the company’s nylon material.
The global and domestic automobile production is rejuvenating, and the lightweight design of automobiles is expected to bring a 10,000-ton application market to high-temperature nylon. The “Technical Roadmap for the Development of Energy-Saving and New Energy Vehicles” issued by the Society of Automotive Engineers of China pointed out that in 2020, 2025 and 2030, the weight of a bicycle should be reduced by 10%, 20%, and 35% compared with 2015, respectively. In the trend of replacing steel with plastic, nylon is an important steel replacement material. In 2017, the average amount of nylon used in each car in my country was about 8kg, and the average amount of nylon per vehicle in the world was 28-32kg. In terms of automobile production, since 2021, with the gradual recovery of the global economy, the situation of the automobile industry has begun to pick up. The domestic auto market trends are in line with the global auto market. According to the Association of Automobile Manufacturers, the domestic automobile production in 2025 will be 30 million units. By 2025, if the average nylon consumption of a single car is 15kg, the domestic automobile industry needs 450,000 tons of nylon materials. High-temperature nylon has performance advantages over traditional nylon 66. As high-temperature nylon gradually replaces traditional nylon applications in automobile production, automotive lightweighting is expected to bring high-temperature nylon to a 10,000-ton application market.
2.4. Polysulfone: Excellent temperature resistance, raw material production capacity construction helps domestic substitution
2.4.1. Polysulfone resin has excellent chemical stability and heat resistance, and good biological safety
Polysulfone is resistant to high temperatures and has good chemical stability. Polysulfone is stable to general acids, alkalis, salts, alcohols, aliphatic hydrocarbons, etc. Good rigidity and toughness, high temperature resistance, thermal oxidation resistance, excellent creep resistance, corrosion resistance of inorganic acid, alkali, salt solution, ion radiation resistance, non-toxic, good insulation and self-extinguishing, easy to shape and process. And can retain the original mechanical properties under steam or other sterilization environment. It has good biological safety and is widely used in feeding bottles. According to the different polymerized monomers, polysulfone can be divided into bisphenol A polysulfone (PSU), polyarylsulfone (PAS), polyethersulfone (PES), polyphenylenesulfone (PPSU), etc., among which PSU, PES , PPSU are three kinds of mature commercial polysulfone, widely used in electrical and electronic, medical and health, food and other fields.
PSU is generally synthesized through the steps of salt formation and polycondensation. Bisphenol A polysulfone can be synthesized from bisphenol A and 4,4′-dichlorodiphenyl sulfone through salt formation and polycondensation. The choice of base and the difference in procedures make the synthesis method divided into one-step method and two-step method. The two-step method first uses water as the solvent, first reacts with bisphenol A and sodium hydroxide to form sodium salt, azeotropically dehydrates with the azeotropic agent, and then adds the solvent and 4,4′-dichlorodiphenyl sulfone to make it polycondensate; one-step method The base used is potassium carbonate, and all the raw materials can be added at the same time without a separate dehydration step, which is beneficial to simplify the process and reduce the reaction time. A two-step method is commonly used in industry.
2.4.2. Polysulfone production capacity is concentrated overseas, and domestic raw materials and product construction go hand in hand
The main production capacity of polysulfone is concentrated overseas. The production capacity of polysulfone in China is limited, and localization is still in the process. In 2021, the global polysulfone production capacity will be about 80,000 tons, mainly in the United States, Western Europe and other regions. The main manufacturers include BASF and Solvay. At present, the number of polysulfone production enterprises in my country is relatively small, and the national production capacity is about 17,000 tons per year, and the performance of domestic polysulfone products is still in the low-end position, and high-end products rely on imports.
4,4-Biphenol is the main raw material for the production of polysulfone. The production capacity of 4,4-Biphenol in my country is small, and there is a big gap with foreign countries in terms of quality. At this stage, it mainly relies on imports. The raw materials and technology limit my country’s Development of the polysulfone industry. With the launch of domestic Sichuan Shengxiao’s annual production capacity of 10,000 tons of 4,4-biphenol, as well as Kingfa Science and Technology (existing polysulfone production capacity of 1,000 tons, and new production capacity of 800 tons), Water Co., Ltd. (current polysulfone production capacity) Domestic manufacturers such as 6,000 tons, with a capacity of 8,000 tons under construction) have accelerated the construction of production lines, and my country’s polysulfone industry has ushered in the accelerated localization process from raw materials to products.
Polysulfone can be used to prepare various advanced membrane materials. The excellent thermal stability, oxidation resistance and biocompatibility of polysulfone bring it a wide range of uses. By combining different functional groups on its molecular main chain, it can be prepared into various separation membranes, etc., so as to be applied to water Processing, fuel cells, medical devices, and food packaging industries. In terms of biomedicine, by doping the surface of polysulfone membrane with antibacterial particles and modified materials, it can effectively sterilize and maintain the high-efficiency separation performance of the membrane; in terms of fuel cells, after modifying the polysulfone membrane, it can effectively meet the fuel requirements. The battery has the requirements for the swelling degree, dimensional stability, proton conductivity and other indicators of the membrane material, so as to make the proton exchange membrane. In 2019, the global consumption of polysulfone was 87,600 tons.
2.5. Polyaryletherketone: a widely used high-performance plastic, China domestic materials have a price advantage
2.5.1. Polyaryletherketone has excellent electrical properties, wear resistance and heat resistance, and polyetheretherketone is the main variety
There are many types of poly(aryl ether ketone), all of which have excellent electrical properties, wear resistance, heat resistance and processability, of which polyether ether ketone is used in the largest amount. Polyaryletherketone (PAEK) is a crystalline polymer formed by linking phenylene rings through oxygen bridges and carbonyl groups (ketones). Due to different structures, there are various types of polyaryletherketones, mainly including polyetherketone (PEK), polyetheretherketoneketone (PEEKK), polyetherketoneetherketoneketone (PEKEKK), polyetheretherketone (PEEK) and so on. PAEK is a new type of special engineering plastic with ultra-high performance, belonging to the polyaryletherketone compound, with excellent electrical properties, flame resistance, radiation resistance, solvent resistance, etc. PEEK is the most used variety in PAEK, accounting for more than 80% of PAEK.
The mainstream synthesis method of PEEK is nucleophilic substitution, the cost of raw materials is high, and the domestic supply gap is large. There are two ways to synthesize PEEK: nucleophilic substitution and electrophilic substitution. The mainstream way is nucleophilic substitution. Nucleophilic substitution is based on 4,4-difluorobenzophenone, hydroquinone and sodium carbonate as raw materials, and diphenyl sulfone as solvent. Under the protection of nitrogen, the temperature is gradually raised to a temperature close to the melting point of the polymer ( 280℃-340℃), the polycondensation reaction occurs to obtain polymer PEEK resin.
The raw material for the nucleophilic reaction requires high-purity 4,4-difluorobenzophenone, and the cost is high, which also leads to the high price of PEEK. In industrial production, high-purity 4,4-difluorobenzophenone is mainly obtained by the Fourier alkylation method and the diazotization method. There are few domestic enterprises producing 4,4-difluorobenzophenone, the production capacity is insufficient, and there is a large gap between supply and demand in the market. In addition to the cost of raw materials, PEEK has many preparation procedures, harsh reaction conditions and high technical requirements, which also lead to the high price of PEEK.
2.5.2. The production capacity of PEEK is mainly concentrated overseas, and China domestic production capacity needs to be improved
Victrex, Solvay and Evonik together account for 88% of the world’s PEEK production capacity, and China’s production capacity accounts for 12%. Currently, Victrex is the world’s largest PEEK producer with a capacity of about 7,150 t/y, followed by Solvay (with a capacity of 1,500 t/y) and Evonik (with a capacity of about 1,250 t/y). The domestic PEEK production capacity is mainly concentrated in the four enterprises of Jilin Zhongyan Co., Ltd., Zhejiang Pengfulong, Changchun Jida Special Plastics and Shandong Haoran Special Plastics. Among them, Zhongyan Co., Ltd. has a maximum production capacity of 1,000 tons per year.
2.5.3. Polyetheretherketone is mainly used in the automotive field, semiconductor preparation field and electronic field
PEEK has applications in the automotive industry, mechanical and chemical fields, aerospace, semiconductor preparation and medical equipment. Because of its high temperature resistance, wear resistance and good mechanical properties, PEEK was first used in the aerospace field to replace aluminum and other metal materials to manufacture various aircraft parts. Later, PEEK was also used in the traditional automobile industry as a built-in engine, automobile bearings, etc., and in the mechanical and chemical fields as valves, pump bodies, piston rings, etc.Good chemical stability and flame retardancy also allowed PEEK to be used as impeller blades. And rocket engine parts are used in the aerospace field. Excellent electrical properties also allow PEEK to be used in wafer carriers, printed circuit boards. PEEK’s excellent chemical stability and corrosion resistance can be used in the field of medical devices.
China domestic PEEK consumption will increase steadily, and domestic enterprises will accelerate the production capacity layout. According to the statistics of “New Chemical Materials”, the global consumption of PEEK has increased from 3,590 tons in 2012 to 5,835 tons in 2019, and the domestic consumption of PEEK in 2021 will be 1,980 tons. According to the China Chemical Information Center, it is expected that China’s demand for PEEK will maintain a growth rate of 15% to 20% in the next five years, and domestic consumption of PEEK will reach 3,354 tons by 2026. At present, Zhongxin Fluorine Materials has begun to produce 5,000 tons of 4,4-difluorobenzophenone, a raw material for PEEK; 2,000 tons of PAEK (including PEEK and PEKK) of Wote Co., Ltd. is also under construction, and the domestic PEEK layout is accelerated.
PEEK can be used in traditional fuel vehicles as components such as bearings. Transportation is an important application area for PEEK. In the field of traditional fuel vehicles, PEEK’s good friction resistance and mechanical properties can be used to replace metal parts such as automotive seals, gaskets, bearings, etc. There are applications in all aspects, which can achieve lightweight. However, compared with high temperature nylon, PEEK is expensive, which limits its wide application in the transportation field.
PEEK has great application prospects in new energy vehicles, especially 800V high-voltage charging lines for electric vehicles. In the field of new energy vehicles, PEEK can also be used as a protective cover, seal, fixed splint for batteries, as well as current collectors, flame retardant sheets, and pole pieces for batteries. In addition, PEEK can also be used as a material for 800V fast charging high-voltage lines. The core advantage of 800V is that it can be fully charged quickly, effectively alleviating mileage and energy replenishment problems, and is the future development direction of new energy vehicles. However, the probability of corona corrosion of 800V charging increases, and the requirements for electromagnetic wires are higher.
Currently, there are two technical routes: thick paint film and thin paint film + PEEK film package. PEEK is a good insulator and can maintain good electrical insulation in harsh environments such as high temperature, high pressure, and high humidity. Compared with the thick paint film process, the thin paint film + PEEK film wrapping process has better comprehensive performance and consistency, and because PEEK has good wear resistance, it can achieve greater space utilization efficiency. According to the annual report of Victrex, as of 2021, the amount of PEEK used in new energy vehicles will be about 20g. It is expected that with the popularization of 800V charging technology and the development of lightweight vehicles, the amount of PEEK used in each new energy vehicle will reach 100g by 2025. According to Bloomberg data, the global production of new energy vehicles is expected to reach 21 million in 2025, and the demand for PEEK will reach 2,100 tons.
In the field of semiconductor manufacturing, PEEK can be used to make a variety of tools. Chemical Mechanical Polishing (CMP) is a key process technology in the wafer production process. The CMP retaining ring is used to fix the silicon wafer and wafer during the polishing process. The selected material should have good wear resistance, dimensional stability, Chemical resistance and easy processing. PEEK is a very suitable material.
Wafer carriers are generally made of materials with temperature resistance, excellent mechanical properties, dimensional stability, and durable, anti-static, low outgassing, low precipitation, and recyclable materials. PEEK can be used to make carriers for general transmission processes. PEEK can also be used to prepare tools for holding wafers or silicon wafers, such as wafer holders, vacuum pens, etc. When clamping the wafer, it is required that the material used will not scratch the surface of the wafer, and there will be no residue to ensure the surface cleanliness of the wafer. PEEK has the characteristics of high temperature resistance, wear resistance, good dimensional stability, low outgassing and low moisture absorption, and will not scratch or contaminate the surface of wafers and silicon wafers.
PEEK is used in the electronics field in connectors, printed circuit boards, high temperature connectors. PEEK has excellent insulating properties, wave permeability, dimensional stability, high temperature resistance and self-lubrication, and can ensure low dielectric constant and loss factor at various frequencies, and can be processed by laser forming technology. Catering to the trend of miniaturization, light weight and intelligence of consumer electronics, it can also be used as a hard-brush circuit board substrate in the 5G field. Other PAEKs are also used in many fields, but due to the high price and complicated preparation, the application scale is small. In addition to PEEK with the largest amount of PAEK, PEKK, PEK, PEEKK and PEKEKK are also widely used in the automotive industry, aerospace, electronic appliances, medical and health and industrial fields.