The Development Status And Problems of The Seven High-performance Fibers And Future Development

The Development Status & Problems of The Seven High-performance Fibers And Future Development

I. Overview of high-performance fibers

High-performance fibers are chemical fibers with special physicochemical structure, properties and uses, or with special functions, generally with very high tensile strength, Young's modulus, and at the same time have high temperature resistance, radiation resistance, combustion resistance, high pressure resistance, acid, alkali, oxidant corrosion and other characteristics, are widely used in aerospace, defense and military, transportation, industrial engineering, geotechnical construction, and even the biomedical and Electronic industry and other fields.

High-performance fibers are an important part of the new materials industry, and are the key materials for the development of China's chemical fiber industry, whose development level is related to the development of national economy and national strategic security. After decades of development, under the joint efforts of the government, enterprises, research institutes and industry associations, China's high-performance fiber industry has paid close attention to key technology research and development, focused on expanding downstream applications, industrial scale, technological advances, system construction, etc., and significantly shorten the gap with developed countries in the last 30 years, and made breakthrough progress and significant achievements. At present, the domestic production capacity of carbon fiber accounts for about 28% of the total global production capacity, aramid accounts for about 23%, and ultra-high molecular weight polyethylene fiber accounts for about 66%.

On the whole, China's high-performance fibers have become the country with the widest product coverage and application scope in the world, and the production scale of carbon fibers, aramid and ultra-high molecular weight polyethylene fibers and basalt fibers ranks among the top three in the world, and the technological level, output and quality of the mainstream products have ranked among the world's advanced level.

The rapid development of domestic high-performance fibers to enhance the core competitiveness of China's manufacturing industry has injected a new impetus to the aerospace, national defense industry, wind power generation, civil engineering and construction, automotive lightweight, marine engineering and other areas of high-quality development has made a significant contribution.

II. The current status of domestic development of high-performance fiber industry

In the national policy support and the strong support of relevant ministries and commissions, through the implementation of various types of science and technology projects, special capacity building and the establishment of national innovation and research institutions, etc., China's high-performance fibers after decades of development, basic research, technology and industry have made great progress, and has established a complete system of high-performance fiber preparation, research and development, engineering practice and industrialization, and continue to make breakthroughs, significantly reducing the gap with developed countries, and now has become one of the most advanced high-performance fiber industry in China. The gap with the developed countries, has become the most extensive coverage of high-performance fiber production varieties in the world. The following is an introduction to the domestic development status of the main high-performance fibers.

1.Carbon Fiber

The research and development of polyacrylonitrile-based carbon fiber in China has a history of more than 60 years. In the early 1960s, Jilin Institute of Applied Chemistry firstly began to study the production technology and process of polyacrylonitrile-based carbon fiber, and completed the continuous pilot plant of carbon fiber production in the early 1970s.

After that, Donghua University, Shanghai Research Institute of Synthetic Fibers, Shanxi Institute of Coal Chemistry of Chinese Academy of Sciences and other scientific research institutions and colleges and universities have also carried out the research and development of polyacrylonitrile-based carbon fiber. After the "11th Five-Year Plan" to "14th Five-Year Plan" period of concentrated technical research, the performance of domestic T300-grade carbon fiber basically reaches the international level, and its application in aerospace field is becoming mature; dry-sprayed wet-processed T700-grade carbon fiber has achieved the production of 1,000 tons, but it is mainly used in the civil field, and its application in aerospace field is mainly used in the civil field, and its application in aerospace field is not. The dry-sprayed wet T700 grade carbon fiber has realized the production of 1,000 tons, but it is mainly used in civil field, and the application in aerospace field is in the primary stage.

At present, China is still in the stage of expanding the application of the 1st generation advanced composite materials with T300 and T700 as the main reinforcing body, and the engineering application of T800-grade carbon fiber is still in the development stage, while foreign aerospace and other fields have already applied the 2nd generation advanced composite materials with T800-grade carbon fiber as the main reinforcing body on a large scale. In the field of carbon fiber, our country is in the running position.

Domestic carbon fiber raw silk formed dimethyl sulfoxide (DMSO), dimethyl acetamide (DMAc), sodium thiocyanate (NaSCN) three kinds of production process system, dry spraying wet spinning and wet spinning process technology is gradually perfected, and the production efficiency is further improved; the core technology of carbon fiber continues to break through, and on the basis of realizing the industrialization of T300-grade carbon fibers, T700-grade, T800-grade, and more than 24K industrial composites are realized successively. level, as well as more than 24K industrial large tow carbon fiber industrial production, at the same time, M40J, M55J and other high-strength and high-modulus carbon fiber breakthroughs in key technologies, in the engineering stage.

However, compared with Japan Toray, China's dimethyl sulfoxide series products have not yet covered the same series of carbon fiber varieties of Japan Toray. T1000 level and above higher performance carbon fiber industrial production technology has not yet made a complete breakthrough, and can not effectively meet the needs of aerospace and defense industry and other fields.

China's carbon fiber production enterprises have Zhongfu Shenying, Lightway Group, Hengshen shares, Jilin Jinggong, Shanghai Petrochemical, in the Jane science and technology enterprises, but due to the lack of basic scientific issues and laws, core technologies and key equipment for systematic and in-depth research and development, product performance and production stability and the gap between the international leading enterprises. High-precision metering pumps, corrosion-resistant spinnerets, ultra-high-temperature graphitization furnace and other equipment is still dependent on imports.

2.Aramid

(1) Para-aramid

Domestic annual consumption of para-aramid is about 1.1kt, of which the amount of fiber optic field is nearly 6000t, the amount of protective materials is about 1000t, the amount of automotive field (hose, brake pads, etc.) is about 2500t, and about 1500t of other industrial use, but 80% of the products still need to rely on imports.

With the rapid development of China's transportation, fiber optic communications, high-speed railroads, aviation reinforcement, lightweight automotive radial tires with cord fabric and brake pads and other fields and protective applications, the demand for para-aramid will show a more vigorous situation, is expected to 2025 domestic demand for para-aramid reached 30kt.

China's early para-aramid producers mainly include Zhonglan Chenguang, Suzhou Zhaoda, Yantai Taihe and Yizheng Chemical Fiber. 2017 Sinochem International Group began to invest in the production of para-aramid, and with the technical support of Donghua University, it relocated the para-aramid production line of Suzhou Zhaoda to Yangzhou and set up a joint venture with it to establish Sinochem High-performance Fibre Materials Ltd. and began the construction of the second phase of the production line of 5kt/a in 2019, which was successfully constructed by the end of 2020. The construction of its second phase 5kt/a production line will start in 2019 and be successfully completed by the end of 2020, with a total production capacity of 5.5kt/a.

Yantai Taihe New Material Co., Ltd. expanded 3kt/a para-aramid production line in Ningxia region in 2020, superimposed on Yantai's 1.5kt/a, there is a total of 4.5kt/a para-aramid production capacity at present, in addition, Taihe New Material is carrying out a technological reform project, which is expected to further increase the production capacity by 1.5kt/a.Taihe New Material acquired Minsdale in 2020 to raise funds for the construction of a 3kt/a production line of High-performance aramid paper-based material industrialization project.

(2) Meta-aramid

Mesoaramid downstream market downturn as a whole, and filtration materials in the field of fierce competition, product prices lower, in addition, mesoaramid raw material prices rose sharply, the double factors lead to greater pressure on business operations.

In this market environment, some companies (including Guangdong Caiyan and Hangzhou Jiulong) have shut down their mesoaramid production lines, resulting in the domestic mesoaramid industry concentration. Currently, the domestic mesoaramid producers are mainly Yantai Taihe New Material Co. and Chaomeis New Material Co. (formerly Sheng'ou Aramid), with production capacities of 7kt/a and 5kt/a, respectively.

In 2018, due to the U.S. military changeover led to the supply of DuPont fiber supply tension and aramid raw material supply tension, caused by the mesoaramid market demand exceeds supply, fiber prices have been increased. 2019, the domestic mesoaramid production to achieve a greater growth, the product is still based on filtration materials and protective materials, the proportion of high-end products domestically produced is still relatively low. The overall operation of the industry is stable, and the products are gradually developing towards differentiation, functionalization and fashion, expanding the application of high-end fields.

At present, the domestic meso aramid manufacturers and the military to cooperate in the production of combat suits, the army and the armed police of the large personnel base and high-frequency battle damage to open up the meso aramid production digestive channels, but also to provide a huge market space. Driven by market demand, taihe new material announced the addition of 4kt/a mesoaramid production line, and put into production in August 2021, the company's mesoaramid production capacity to reach 10,000 tons.

(3) Aramid III

Aramid Ⅲ production line was firstly built by China Blue Chenguang Chemical Research Institute Co., Ltd. in 2009, and started the production of Staramid F-368 and F-358 series products, with the performance comparable to that of Russian Armos, and the capacity of 50t/a, which solves the problem of "availability" of heterocyclic aramid localization in China, and fills the gap in China. The domestic blank.

After 2013, China Blue Chenguang began to devote to the research and development of the production technology of second-generation aramid Ⅲ, and obtained a kilogram grade fiber sample in early 2015, with excellent mechanical properties. After that, the design of spinning assembly was further optimized, and the spinning of single spinning position 200-300tex tow was realized, with the same performance level as 75-100tex tow, i.e., the density of stranded tow was increased by 3 times.

At present, the domestic aramid Ⅲ tensile strength of 5.0GPa, modulus of elasticity of 130 ~ 160GPa, performance of the domestic batch production of organic fibers in the first, to the level of Russia Rusar batch products, has been batch stabilization of production and used in the field of military industry, to solve the national defense urgently needs, is of great significance. In addition to the blue Chenguang, domestic and Guangdong Caiyan Co., Ltd. and Sichuan Huiteng Technology Co., Ltd. and China Aerospace Science and Technology Sixth Academy 46 have carried out the research and development work of heterocyclic aramid.

In 2008, the national "Ninth Five-Year Plan" key scientific and technological research projects undertaken by Guangdong Caiyan heterocyclic aramid project and the core raw material of heterocyclic aramid M-3 monomer development project passed the acceptance of the Ministry of Science and Technology. 2010, the independent research and development of Sichuan Huiteng production of the commodity called "Fusite "Heterocyclic aramid passed the test of national authoritative institutions, and further developed heterocyclic aramid composite plate profiles and molded components, now has 50t/a aramid Ⅲ and 100t/a aramid Ⅲ advanced composite materials production capacity.

China Aerospace Science and Technology Sixth Academy 46 began to study F-12 heterocyclic aramid in the 1990s, through the polymerization - spinning - post-processing fiber process continues to optimize and improve the success of the research in 1999, followed by 3t/a pilot, 5t/a amplification and 20t/a industrialization and product application technology, the first to design and develop a variety of specifications of the F12 fibers and their fabrics in China, and its performance has reached the international advanced level, with a capacity of 50t/a advanced composite materials. It has reached the international advanced level with the production capacity of 50t/a, and is preparing to expand the F-12 production capacity to 100t/a recently to meet the demand of China's aerospace and high-end strategic weapons.

3.UHMEPE fiber

With the development of UHMWPE fiber in the military, civilian products, especially a large number of various types of cables and home textiles and other areas of application, the domestic demand for UHMWPE fiber steadily increasing, fiber production capacity has been gradually expanding. 2010 China's UHMWPE fiber manufacturers more than 20, with a total production capacity of 17kt/a, to the development of more than 30 to 2015, with a total capacity of 26.6kt/a.

However, there are only 8 enterprises with annual production capacity of 1,000 tons among more than 30 UHMWPE fiber producers, and most of them have a capacity of only about 300t/a, with a single product and high production cost.

In 2016, Jiangsu Jiujiu purchased the patent of Donghua University and began to build a UHMWPE fiber production line, becoming the first domestic enterprise with a production scale of 10,000 tons of UHMWPE fibers, and its fiber products were put into the market, which triggered a price war of domestic UHMWPE fibers. After that, some of the enterprises with backward technology and process gradually withdrew from the UHMWPE fiber market, while some of them rebuilt their fiber production line through restructuring or absorbing capital, and a number of new enterprises invested in UHMWPE fiber industry.

At present, the UHMWPE fiber production capacity of JiuJiu has reached 16kt/a. In addition, Shandong Ruyi Group announced in 2018 to invest in the construction of UHMWPE fiber production line, with a production capacity of 10kt/a; Zhejiang YiJu and Jiangsu Leader also started to invest in the UHMWPE fiber industry after 2018, with an expected production capacity of more than 3kt/a. After the completion of all these enterprises production line, China's UHMWPE fiber production capacity will exceed 60kt/a, accounting for 3/4 of the global production capacity.

Domestic UHMWPE fiber and products in the international market competitiveness has also been improving, foreign trade exports have gradually increased from 50% to more than 70%. At present, there are more than 20 domestic UHMWPE fiber production enterprises, of which the production capacity of more than 1,000 tons of production enterprises as shown in Table 8.

4.PPS fiber

Domestic polyphenylene sulfide resin manufacturers are mainly Zhejiang Xinhecheng, Chongqing Poly Lion, Inner Mongolia Panxun and Zhuhai Changxian. 2020 October, the State Ministry of Commerce issued a policy on the United States, Japan, South Korea, and Malaysia's four imports of PPS, the implementation of the deposit form of anti-dumping measures, significantly increase the price of imported products, prompting domestic enterprises to enhance the cost-effectiveness of the product, for China's PPS resin industry Rapid development of China's PPS resin industry to provide the basis.

Zhejiang Xinhecheng, Chongqing poly lion production accounted for 9.6% of global production and 6.4%, the future is expected to expand production capacity to become a global PPS production capacity of the top five companies. However, due to the PPS fiber industry applications are not fully developed, the demand is much lower than the application of PPS resin in the field of electrical and electronic. Therefore, Chongqing poly lion company mainly focuses on PPS injection molding raw materials research, fiber-grade slice product research is less, a single product.

At present, only Zhejiang Xinhecheng built 5kt / a capacity of fiber grade resin production line, the production of a variety of batch number of meltblown grade, staple fiber grade chips, but its lack of filament grade and modified grade spinning chips, fiber product quality is lower than the international level.

Domestic also only Zhejiang Xinhecheng and Sichuan Anfer Polymer Material Technology Co., Ltd. can achieve continuous production of PPS staple fibers, with a capacity of 5kt/a and 3kt/a respectively; Jiangsu Ruitai Science and Technology Co., Ltd. and other staple fiber producers such as Sichuan Deyang Technology Co.

In 2016, Suzhou Jinquan New Materials Co., Ltd. and Donghua University jointly undertook the transformation of scientific and technological achievements in Jiangsu Province, to achieve the modification of PPS staple fibers research, and built a 3kt/a flexible production line, significantly improve the flame retardancy of PPS fibers, the service temperature and life, and improve the competitiveness of PPS staple fibers in the international market, but due to the shortage of raw materials for fiber-grade resins, it is not possible to sustain production.

To sum up, the polymerization production technology of domestic PPS resin has been accumulated to a certain extent, and under the dual support of national policy and market demand, the industrial scale has been gradually expanded and the market share has been greatly increased, but there are still problems such as lower level of production technology, fewer product categories, lack of filament-grade and meltblown-grade products, and lower than the international advanced level of high-end products; in terms of the fiber industry, the production capacity of high-end fiber-grade chips is insufficient, the market application field is narrow, and the production capacity of medium-grade fiber is lower than the international advanced level. In the fiber industry, the production capacity of high-end fiber-grade slices is insufficient, the market application field is narrow, the competitive environment of the low-end product market is poor, and the high-end application market is seriously lacking.

High-temperature soot filter bag field, although there is still more than 50% of the market vacancy, but with the optimization and upgrading of electrostatic precipitator technology and new high-performance fiber market impact, PPS fiber market saturation, the urgent need to expand the field of application. Industrial clusters, based on fierce market competition and fiber production process difficulty, conventional product price competition, low profits, high entry threshold, most small and medium-sized enterprises are forced to transform and develop, it is difficult to achieve the industrial cluster effect, the domestic PPS high-quality development of slow speed.

5. PBO fiber

Domestic research on PBO fiber started late in the 1980s, East China University of Science and Technology took the lead in the study of PBO monomers and polymers, the tensile strength of the prepared fiber is only 1.20GPa, modulus of 10GPa, the performance is far from reaching the level of Kevlar fiber. Due to the monomer 4,6-diaminoresorcinol hydrochloride (DAR), the monomer for synthesizing PBO, is completely dependent on imports, which is expensive, restricting the research related to PBO, and the research of PBO fibers has been interrupted for several times. In order to fill this gap, the state has included PBO high-performance fibers as a key material in the 863 national program for support.

In this context, East China University of Science and Technology, Shanghai Jiao Tong University, Harbin Institute of Technology and other special research on the synthesis of DAR monomer; Harbin Institute of Technology, East China University of Science and Technology, Donghua University and other units of PBO polymerization and fiber preparation research, and a number of other research institutes on the applications and reinforcing materials for PBO research.

After two to three decades of development, domestic universities and research institutes have made some progress in the synthesis and spinning of PBO polymers. Donghua University and Shanghai Jiao Tong University since 1999 began to carry out PBO polymerization, fiber forming research, has conquered the monomer synthesis and purification technology, designed and manufactured for high viscosity polymerization system of special stirrers, invented the PBO reaction extrusion - Liquid Crystal Spinning integrated process, the first time in China, successfully built a ton scale PBO fiber test line, completed in 2005, the project was identified, the resulting PBO polymer synthesis and spinning. Appraisal, produced PBO polymer characteristic viscosity of 25dL / g or more, strength of 4.16GPa, modulus of 139GPa; after that, continue to expand the test, on the original scale to improve and expand the production of PBO polymerization, spinning pilot line built on the scale of 5t, completed in 2008 the project appraisal, the production of PBO fiber strength stabilized at 4.95GPa or more, close to the level of the Japanese Toyobo fiber product level.

Around 2016, Harbin Institute of Technology to trichlorobenzene as raw material synthesized DAR monomer purity of 99.5% or more, using the monomer for the polymerization of PBO and spinning, spun PBO fiber tensile strength of 5.0GPa, modulus of 240GPa.

In the industrialization of PBO fiber, the country has also made important progress in recent years, several PBO fiber production enterprises have been put into production. During the 12th Five-Year Plan period, China Blue Chenguang Chemical Co., Ltd. built a 2t/a capacity PBO fiber military small pilot line, whose fiber strength is stable to more than 5.2GPa, and is expanding it to 20t/a capacity.

In January 2018, Chengdu New Morning New Material Technology Co., Ltd. invested about 500 million yuan to build a high-performance PBO fiber production line with an output of 380t/a, which is the largest production line in China at present; in August 2018, Jiangsu Zhonghui Special Fiber New Material Company's high-performance PBO special fiber project was successfully test-produced, and the project's first phase has a production capacity of 50t/a; in the same year, Zhongke Jinqi New Material Science and Technology Co. Ltd. invested 145 million, built 150t / a PBO production line.

In recent years, Shandong Institute of Non-metallic Materials for military demand and Donghua University to jointly promote the industrialization of PBO fiber construction, in 2021 in Jinan, Shandong Province, built a hundred tons of PBO fiber production line. From a comprehensive point of view, the country is still in the early stages of industrialization of PBO fiber, fewer products on the market, yet to be further developed.

6.Silicon carbide fiber

In order to break the United States, Japan and other developed countries on the SiC fiber technology and products of the tight blockade, the National University of Defense Technology from 1980 to take the lead in the preparation of continuous SiC fibers in the country's research, independent research and development and the establishment of the first domestic production of continuous SiC fibers test line, in the precursor synthesis, spinning, non-melting and sintering, etc., have achieved products and technologies with independent intellectual property rights.

The performance of the prepared KD-type first-generation and second-generation continuous SiC fibers are in the domestic leading and international advanced level, which have been used by many research units and application departments in domestic aviation, aerospace and other fields, and have been awarded the first prize of the Army's Scientific and Technological Progress (2014), the first prize of the Hunan Provincial Technological Invention (2014), and the second prize of the National Scientific and Technological Progress (2015).

For the development of third-generation SiC fibers, through hydrodecarburization pre-sintering, the third-generation continuous SiC fibers of type KD-S with near stoichiometric ratio were prepared, and the performance was comparable to the level of Japan's Hi-Nicalon S fibers, which also used the hydrodecarburization process; the technology of high-temperature sintering and densification of SiC fibers was conquered in 2016, and the first time in China that the continuous high-crystalline near stoichiometric ratio of SiC fibers, i.e., KD-S fibers, was successfully prepared. SiC fiber, i.e., KD-SA type third-generation SiC fiber, which is comparable to the level of foreign third-generation SiC fiber Tyranno SA in terms of composition and structure, high temperature resistance and creep resistance.

At present, the fiber has been realized in small batch production and provided to the application departments to use, filling the gaps in the country, so that China has become the world's third country capable of preparing a high crystalline near stoichiometric ratio of continuous SiC fibers.

Xiamen University from 2002 into the preparation of continuous SiC fiber research field, using electron beam irradiation crosslinking method to obtain a low oxygen content of the second generation of continuous SiC fibers, and the use of electron beam irradiation and then hydrodecarbonization method to prepare the third-generation continuous SiC fibers similar to the Japanese Hi-Nicalon S fibers, the composition, structure and performance of the fibers are comparable to the Japanese corresponding to the level of the second and third generation of continuous SiC fibers. The composition, structure and performance of the fiber are comparable to the corresponding second- and third-generation continuous SiC fibers from Japan.

Since 2015, Ningbo Institute of Materials, Chinese Academy of Sciences (NIMCS) has been carrying out the development of third-generation SiC fibers similar to Japan's Hi-Nicalon S fibers in response to the application needs in the nuclear industry. In addition, the Institute of Process of Chinese Academy of Sciences has conducted relevant research on zirconium-containing complex-phase SiC fibers, and Zhongnan University has conducted relevant research on beryllium-containing SiC fibers.

In terms of industrialization, in 2005, Suzhou Saifi Group Co., Ltd. docked with the University of National Defense Technology to transform the results, and in 2010, the first time in China to realize the industrialization of continuous SiC fibers. 2016, Ningbo Zhongxing New Materials Co., Ltd. signed a cooperation agreement with the University of National Defense Technology to carry out the industrialization of the second generation of continuous SiC fibers, and has completed the production line of the polycarbon-silane pioneer with a capacity of 40t/a and 10t/a of the polycarbon-silane pioneer. body production line and 10t/a second-generation continuous SiC fiber production line (Shincolon-II).

In 2019, the company signed a cooperation agreement with the Institute of Process Technology of the Chinese Academy of Sciences to transform the second-generation continuous complex-phase SiC fiber (Sericafila Z) as well as the third-generation continuous complex-phase SiC fiber (Sericafila ZB). Since its establishment in 2015, Fuzhanya New Material Co., Ltd. has cooperated with Xiamen University to build the industrialized production line of second-generation SiC fiber and third-generation SiC fiber with a capacity of 10t/a. In 2018, Hunan Boxiang New Material Co., Ltd. has built the capacity of 10t/a beryllium-containing SiC fiber with independent intellectual property rights (10t/a beryllium-containing SiC fiber) through the transformation of scientific and technological achievements of Central South University. 10t/a beryllium-containing silicon carbide fiber production line.

7.Basalt fiber

In 2002, the Ministry of Science and Technology will be "basalt continuous fiber and its composite materials" included in the "863 program", to strengthen the independent intellectual property rights of the gas-electric mixing and all-electric melting furnace production technology development and promotion, so that the rapid development of basalt fiber. But at present, China's basalt fiber overall take the low-end route, focusing on the concrete with short-cut basalt fiber reinforcing materials. 2006, China's first basalt fiber production line developed by Shanghai Ruskin Basalt Fiber Co.

At present, there are about a dozen enterprises engaged in the production of basalt fibers in China, with a total production capacity of more than 100kt, and a number of enterprises with 10,000-ton production lines, including Jilin Tongxin, Henan Dengfeng Power Plant Group, Sichuan Glass Fiber Group, Sichuan Qianyi, Guizhou Shixin, etc. However, most of the enterprises have an actual production capacity of a few hundred to a few thousand tons.

The actual total production of basalt fiber in China is 20-30kt, specifications are mostly between 10-20μm, the price per ton is 12,000 to 20,000 yuan, mainly used in cement concrete, asphalt concrete, vehicle traffic, high temperature filter bags and thermal insulation felt and so on.

Domestic basalt fiber production enterprises are still in the low price homogenization competition stage, on how to improve the performance of basalt fibers, still need to be further explored. 1200 holes and more than the large bundle drawing technology is still unstable, need to be from the raw materials, melting and fiber technology and other aspects of the start to overcome the technical difficulties. Only by solving the large tow drawing technology, can we improve the quality and stability of basalt fiber, really play the basalt fiber high strength, high modulus and other characteristics, to broaden the scope of its application, break through the bottleneck of the development of basalt fiber. Table 9 summarizes the production situation and characteristics of the main producers of basalt fiber in China.

III. The current problems of high-performance fibers

China's high-performance fiber development did not start late, but due to financial investment, raw materials, equipment, personnel and other complex reasons progress has been slow, in the past 10 years, although a lot of progress has been made, but in terms of stability of product performance, production costs, scale and application level with Japan, the United States and other developed countries there is still a significant gap between the main common scientific problems of high-performance fibers in the proximity, long-distance and macroscopic structure (i.e., molecular chain distribution, purity of the system, and the application level). The main common scientific problem is the high performance fiber proximity, remote and macroscopic structure (i.e., molecular chain distribution, system purity, condensed structure, fiber surface structure) caused by the inhomogeneity of the product spinnability, physical and chemical properties and batch stability is insufficient. The main problems that exist at present are summarized as follows:

High-end fibers still exist generation difference, the independent guarantee ability needs to be strengthened. Foreign aerospace field has been large-scale application of T800-level carbon fiber as the main reinforcement of the second generation of advanced composite materials, while China is still in the first generation of advanced composite materials in general to expand the application of advanced composite materials, the second generation of advanced composite materials assessment and verification stage. High-strength and high-modulus, ultra-high modulus carbon fiber, differentiated para-aramid (ultra-high-strength, ultra-high model, medium modulus, high bonding, fatigue resistance, etc.), high-strength and creep-free UHMWPE fiber, high-performance heterocyclic aramid Ⅲ production technology has not yet made a breakthrough, does not have the ability to independently ensure that in the field of high-performance inorganic fibers, there is the same lack of high-end products, quality consistency and other issues.

High-performance fiber industry technology maturity is not enough, large-scale high-end equipment and complete sets of technology is still not a complete breakthrough. High-performance fiber industry is a production process and equipment is highly coupled with the long process of fine industry, the country has not yet fully mastered the large-scale complete sets of production process technology.

At this stage, domestic carbon fiber production is still 12K and the following small tow products, large tow, low-cost carbon fiber industrial production technology has not yet made a full breakthrough, while foreign countries have begun to large tow of low-cost and small tow of high-quality production technology integration, and constantly improve product quality and reduce production costs. Aramid (para-aramid, meso-aramid, heterocyclic aramid Ⅲ) in the product performance and stability, production efficiency, industrial scale, application areas and other aspects of the gap still exists.

UHMWPE fiber single line capacity is low, high investment costs, low production efficiency, high energy consumption, large-scale low-cost production is still difficult to achieve.PPS fiber and polyarylate fiber lack of kiloton industrialization of complete sets of technology and equipment. In addition, the industrialization of high-performance fiber complete sets of equipment design and manufacturing capacity is insufficient, the lack of design/simulation engineers, design/simulation software relies on imports, there is an obvious gap between the basic industrial technology (such as mechanical processing), precision equipment (such as metering pumps, spinnerets), the quality of raw materials for the equipment (such as high-strength steel, corrosion-resistant steel materials, etc.) and foreign countries, which leads to a lack of domestic independent equipment in terms of precision, efficiency and service life, equipment operation stability and stability of the equipment. The service life of the domestic independent equipment in terms of precision, efficiency and service life is insufficient, poor operational stability of the equipment, high failure rate, restricting the performance of China's high-performance fiber products to stabilize and improve and control production costs.

Insufficient investment in basic research, part of the key scientific issues have not been explored, the lack of cutting-edge product innovation and development momentum. Under the traction of national policy support and major tasks, China's high-performance fibers in reference to, imitation of foreign products to carry out research work, product development is the main focus, focusing on solving the country's major needs and applications of urgent needs.

Universities and research institutions are usually based on model products, high-performance fiber materials composition - structure - process - performance of the deep relationship between the law has not yet been fully grasped, the necessary basic scientific mechanisms and theories have not been revealed clearly, resulting in a lack of theoretical support for the face of new application needs, the lack of independent innovation. Enterprises are tired of blindly expanding production, investment in research and development funds are seriously inadequate, such as carbon fiber can be industrialized domestic products only a few grades, while Japan Toray has nearly 20 product models.

Sound industrial system has not yet formed, there is still low-level duplication, disorderly competition. At present, China's high-performance fiber industry system is not complete, key equipment and supporting materials, important raw materials, product standards and testing and evaluation of weak links.

In the aerospace, defense and military applications in the field of small overall scale, it is difficult to drive the development and improvement of the whole industrial chain of high-performance fibers and composites, in the automotive, pressure vessels, rail transportation and other industrial areas represented by the large-scale application has not yet been achieved. Stimulated by multiple factors such as national policy support and the urge to invest in high-tech areas, there are still low-level repetition, detached from the industry's actual investment in the chaos, the level of the project varies, which not only causes a large number of national and social resources occupied and wasted, and at the same time, is not conducive to the formation of the industry's competitiveness and sustainable industrial ecology.

IV. The future development of high-performance fibers

High-performance fibers are indispensable strategic new materials for China's national economic development and national defense construction. In recent years, China's high-performance fibers in the industrialization of technology, product variety and quality, market application and other aspects of rapid development, high-performance fibers have become a new driving force for the upgrading of the manufacturing industry, China has gradually become the world's most extensive coverage of varieties of high-performance fibers production and consumption of large countries.

This is highlighted in: First, the localization of high-performance fibers to break the Japan, the United States and other developed countries in China's long-term technology blockade and market monopoly, for China's manufacturing industry to enhance the core competitiveness of the new impetus for the aerospace, national defense and military industry, wind power generation, civil engineering and construction, automotive lightweight, marine engineering, environmental protection and other areas of high-quality development has made a significant contribution.

Relevant data show that for every 100kg of car body weight reduction, O2 emissions will be reduced by about 5g/km; for every 20% reduction in aircraft body weight, CO2 emissions will be reduced by about 140 tons per year. In the carbon peak, carbon and policy background, carbon fiber has been applied to photovoltaic, wind power, hydrogen and other green and clean energy fields, is gradually becoming an important way to achieve the "dual-carbon" strategic objectives.

Secondly, with the continuous improvement of domestic high-performance fiber market acceptance, not only the economic benefits of the main enterprises continue to improve, and gradually enter a benign stage of development, while high-performance fibers and their products exports are also growing, and the competitiveness of products in the international market continues to strengthen.

Carbon fiber industry, for example, in 2012 Weihai Guangwei Composites Co., Ltd. for the first time to achieve profitability of carbon fiber enterprises, in 2016 Zhongfu Shenying Carbon Fiber Co., Ltd. for the first time to achieve profitability of carbon fiber enterprises in the field of civil use. 2002 in the new Crown Epidemic continued to wreak havoc in the background, China's carbon fiber industry against the trend, and continue to maintain the production and sales of two booming, growing performance for two consecutive years to achieve a profit for the whole industry. Profitability of the whole industry.

In May 2022, the Ministry of Industry and Information Technology, the Development and Reform Commission and two ministries and commissions jointly issued the "Guiding Opinions on the High-Quality Development of the Chemical Fiber Industry", which mentioned that the promotion of the chemical fiber industry's innovation capacity is constantly increasing, the intensity of the industry's R & D investment has reached 2%, and the R & D and manufacturing capacity of high-performance fibers meets the needs of the national strategy.

Improve the quality consistency and batch stability of high-performance fibers, and further expand the application of high-performance fibers in aerospace, wind and photovoltaic power generation, marine engineering, environmental protection, safety and protection, geotechnical construction, transportation and other fields.2022 September, the Ministry of Industry and Information Technology, the State-owned Assets Supervision and Administration Commission (SASAC), the General Administration of Market Supervision, the Intellectual Property Office and other four departments jointly issued the "Raw Material Industry". The "Three Products" Implementation Program" proposes that by 2025, the variety of raw materials will be richer, the quality will be more stable, and the brand will be more influential.

High-temperature alloys, high-performance special alloys, semiconductor materials, high-performance fibers and composites, and other products and services in key areas to significantly enhance the support capacity. Although in the high-end field of China's high-performance fiber industry independent innovation capacity is still to be improved, but domestic enterprises have been exploring the core technology, and gradually break the foreign monopoly, the localization rate is expected to steadily increase.

In August 2023, the Ministry of Industry and Information Technology issued the "New Industry Standardization Pilot Project Implementation Plan (2023-2035)", mentioning the development of high-performance fibers, special materials and other advanced polymer material standards, research performance characterization and test method standards.

To promote the further development of China's high-performance fiber industry and improve its international competitiveness, it is recommended to:

Strengthen the top-level design and enhance the leading role of the government. Currently facing rapid changes in the international environment, should be led by the relevant state ministries and industry associations, planning the development of China's high-performance fiber industry new path, to protect the industry's sound development, to prevent the growth of homogeneous production capacity is too fast, to avoid taking the old way of conventional fiber development, affecting the future sustainable development of the industry. Support scientific and technological research and development and demonstration applications, adhere to long-term investment, encourage iterative and stable development, promote the research and development of innovative products and large-scale application, high-performance fiber materials technology progress to drive industrial upgrading.

Strengthen R&D innovation and deepen the combination of industry, academia and research. Increase independent innovation, focus on collaborative innovation, build an enterprise-oriented, market-oriented, industry-university-research combination of technological innovation system, enhance the endogenous momentum, and promote the high-quality development of the industry. Increase efforts to solve the common problems restricting the high-quality development of the industry, focus on short board problems, strengthen the research and development of high-quality raw and auxiliary materials, key equipment and components, enhance the independent and controllable ability of the industrial chain supply chain, master the deep relationship between the composition of high-performance fibers-structure-process-performance law, and comprehensively enhance the ability of independent innovation.

Expand production scale and develop low-cost process technology. While focusing on product performance and research and development of high value-added products, we attach importance to the development of a variety of molding process technologies to further reduce costs and strengthen the revenue capacity. Production cost determines market capacity and application, and accelerating the development of low-cost technologies is conducive to expanding the scope of application. Expanding the scale of production and increasing the production capacity of a single line can further improve production efficiency and reduce production costs, thus enhancing the market competitiveness of products.

Increase the development of application technology in response to market demand. Through the "downstream" to drive the "upstream", to form a series of products with independent intellectual property rights, to strengthen communication and cooperation with supporting industries, and to actively integrate into the research and development of downstream customers from the design of finished products, so as to efficiently maximize the performance of high-performance fibers in application scenarios. The performance of high-performance fibers is maximized in the application scenarios, so as to realize the accurate matching between their performance and downstream applications.

Establish a monitoring system to grasp the dynamics of the industry. Improve high-performance fiber industry statistics, focus on industry data research, strengthen industry management and guidance, planning and development, formulate and improve industry access conditions, release product guidance directory, to avoid blind development and low-level duplication of construction, and encourage the promotion of synergistic linkage between manufacturers, in-depth communication, to guide the benign development of high-performance fiber industry.

Strengthen the construction of standards and promote participation in international competition. Focus on the construction of national and industrial standards for high-performance fibers, including carbon fiber, aramid fiber, polyimide fiber, polyarylate fiber, polyphenylene sulfide fiber, UHMWPE fiber, etc., and their various downstream products, as well as product standards, in order to regulate the domestic products of high-performance fibers, and to promote the entry of the products into the international market and participate in international competition.