Carbon fiber out of the low end of the Breakthrough Road

recently, Jiangsu Lianyungang Shenying Bicycle Co., Ltd. produced a 6kg carbon fiber bicycle with independent intellectual property rights, and its main raw material carbon fiber was all provided by Zhongfu Shenying Carbon Fiber Co., Ltd. This kind of bicycle has passed the European carbon fiber bicycle quality certification, and the price is only one third of the same kind of imported carbon fiber bicycle. The first phase of the company’s annual output of 100000 carbon fiber bicycles will start construction within this year. Compared with ordinary bicycles, carbon fiber bicycles are light, durable and energy-saving. As a bicycle body material, this is only a small example of the application of carbon fiber

carbon fiber is getting closer and closer to our daily life. The density of this fibrous carbon material is less than 1 / 4 of that of steel, but its tensile strength is 7-9 times of that of steel, and its tensile elasticity is also higher than that of steel. Carbon fiber is lighter and harder than aluminum. Because of its light weight, the carbon fiber composite is about 20% of steel. According to the fiber grade and directivity, it can even reach the strength of similar steel. 1n addition, carbon fiber is not rusty. Using carbon fiber materials can greatly reduce the weight of products, thus significantly improving fuel efficiency. Aircraft and automobiles produced with carbon fiber materials can save a lot of fuel

due to its high strength, high modulus, high temperature resistance, corrosion resistance, electrical and thermal conductivity, carbon fiber has become a new chemical material with two characteristics of strong tensile strength of carbon material and soft processability of fiber, which is a new generation of reinforced fiber. At present, carbon fiber is not only widely used in aerospace, military industry, but also in automotive components, wind turbine blades, nuclear power, oilfield drilling, sporting goods, carbon fiber composite cable and building reinforcement materials< The first dilemma is that the production technology of carbon fiber is far behind that of developed countries. For a long time, Japan, the United States and other major production companies have not only kept the high-performance special precursor preparation technology highly confidential, refused to transfer, nor sold high-performance special precursor products, but also had little possibility of introducing complete sets of technology< According to he Fu, a researcher of Shanxi 1nstitute of coal chemistry, Chinese Academy of Sciences, a breakthrough has been made in the industrialization of T300, with 100 ton and 1000 ton carbon fibers put into production; T700 is under pilot scale-up and T800 is under laboratory development. At present, the product quality of one or two units in China has exceeded the performance index of T300, reached the level of T400, and can be produced in small batch. This is at the level of Toray's carbon fiber research and development in the 1980s. From the overall situation, China is currently in the transition period from T300 universal level to T700 and T800 with high performance< However, due to different application fields, the quality requirements of carbon fiber and its composites are also different. 1n other words, only general-purpose T300 is far from meeting the market demand. Therefore, Hefu believes that it is necessary to develop T700, T800 and T1000 grade carbon fibers with high performance. For example, he said that the primary structural materials for manufacturing large aircraft need to use t800h grade and its composite material p2302 (t800h / 3902-2); T700s grade is also required for manufacturing carbon fiber composite core aluminum stranded cable (ACCC). Therefore, it is urgent to develop high performance carbon fiber. The leading products in the future should be T700 and T800, and T700 will gradually replace T300 to become a new generation of general-purpose carbon fiber< The second dilemma is: small scale, large quantity and repeated research and development. The research on carbon fiber in China is not too late. Although some progress has been made, the development is relatively slow for many years. According to Qian Bozhang, founder of Jinqiu energy and chemical workshop of Shanghai Qingdu 1nformation Technology Co., Ltd., the research on PAN based carbon fiber was initiated by Changchun 1nstitute of Applied Chemistry, Chinese Academy of Sciences in the 1960s, and the continuous pilot plant was completed in the early 1970s. Since then, Shanghai Synthetic Fiber Research 1nstitute, Shanxi 1nstitute of coal chemistry, Chinese Academy of Sciences, Beijing University of chemical technology and Shandong University of technology have also started their research work. They passed the pilot plant in the mid-1980s and entered the stage of industrial pilot production. They have successively built small-scale pilot plants with an annual output of several hundred kilograms to several tons and pilot plants with an annual output of dozens of tons. But on the whole, there is a big gap between China and foreign countries in terms of technology level, production capacity and product quality since the beginning of the 21st century, the domestic carbon fiber industry has developed rapidly. Anhui Huawan Carbon Fiber Co., Ltd. has taken the lead in introducing an annual production unit of 500 tons of precursor fiber and 200 tons of PAN based carbon fiber, successfully filling the gap in the industrial production of carbon fiber and precursor fiber in China since 2000, China’s carbon fiber technology has been diversified, abandoning the original nitric acid precursor manufacturing technology and adopting the one-step wet spinning technology with dimethyl sulfoxide as solvent. At present, a few domestic carbon fiber products developed with independent technology have reached the international level of similar products< According to Qian Bozhang, in recent years, the industrialization of carbon fiber technology has been regarded as a strategic task in China by relevant ministries and commissions. Subsequently, some enterprises have joined the ranks of carbon fiber production. At present, China has Jilin Shenzhou Carbon Fiber Co., Ltd., Shandong Tiantai New Material Co., Ltd., Zhejiang Jiaxing Zhongbao Carbon Fiber Co., Ltd., Baoding swan chemical fiber group, Dalian Xingke Carbon Fiber Co., Ltd., Shanxi Hengtian Textile New Fiber Technology Co., Ltd. and other carbon fiber manufacturers with different production sizes, with a total annual production capacity of 2310 tons. According to incomplete statistics, there are 11 proposed and under construction carbon fiber production enterprises, with a total production capacity of 7100 tons of precursor fiber and 1560 tons of carbon fiber. Among them, there are 4 enterprises under construction, with a total production capacity of 1100 tons of precursor fiber and 470 tons of carbon fiber< 1n contrast, there are no more than 12 large-scale enterprises in the world due to the complex production process of carbon fiber. They are Toray, topang and Mitsubishi Liyang in Japan, Cytec, Hexcel, Zoltek and Amoco in the United States, SGL in Germany, Taiguang in Korea and Formosa Plastics in Taiwan. Among them, the leading manufacturers are Mitsubishi Liyang, Toho and Toray of Japan, as well as Cytec and Hexcel of the United States< 1n 2008, many new chemical material projects including carbon fiber were launched and implemented in China. With the increasing demand for carbon fiber products in various fields, many carbon fiber research projects or thousand ton industrialization projects were launched. However, due to the lack of core industrialization technology with independent intellectual property rights in China's carbon fiber industry, industrial development will not be achieved overnight, but the development opportunity has come according to the introduction, it is more difficult from technology research and development to industrial transformation, so it will take a long time for carbon fiber to truly realize localization. Due to the shortage of market, there has been a “carbon fiber fever” in China in recent years. However, it should be pointed out that although there is a large demand for carbon fiber products in the domestic market at present, there is a great risk of blind development. After a few years of implementation of these thousand ton projects, it is inevitable that the market will be surplus according to the prediction of relevant departments, the world demand for carbon fiber will grow rapidly at a rate of about 13% every year. The global demand for PAN based carbon fiber will reach 50000 tons in 2010, 60000 tons in 2012 and 100000 tons in 2018< To this end, seven global carbon fiber manufacturers (Toray, Toho, Mitsubishi, SGL, Hexcel, Cytec and Zoltek) have announced plans to expand production by 78% in the next three to five years, with a total investment of 879.7 million euros. Relevant experts predict that in the short run, carbon fiber will be in short supply, but by 2012, supply may exceed demand the first way to break through the encirclement: clench your fist to form a joint force how to quickly improve the upgrading pace of China’s carbon fiber industry under the prospect of supply exceeding demand? Qian Bozhang believes that among the many reasons restricting the development of carbon fiber in China, the backward level of PAN precursor is the bottleneck restricting the improvement of carbon fiber production level, which not only affects the quality of carbon fiber, but also affects its output, production cost and market competitiveness at present, it is urgent for China to master the production technology of high-performance PAN based precursor and seize the market opportunity. On the premise of improving the production technology of carbon fiber, we should make a breakthrough in the manufacturing technology of PAN based precursor as soon as possible, develop high-quality upstream product lines, ensure the stable production of carbon fiber and high-quality products, so as to break the blockade and monopoly of foreign countries in key technologies for this reason, major scientific research institutions and enterprises should make joint efforts to avoid the phenomenon of repeated introduction and research, avoid detours and save costs< Qian Bozhang suggested that the state's support should mainly focus on the establishment of a systematic research network, and increase investment, tax, credit and other policies to encourage carbon fiber production enterprises, raw material production enterprises and powerful investment enterprises, especially for pioneering enterprises. Although China has a clear plan and target for the production of carbon fiber, the phenomenon of repeated introduction and repeated research is still very serious. The state should focus on supporting several successful enterprises, vigorously cooperate, optimize the layout, integrate resources, cooperate in tackling key problems, prevent low-level repeated construction and blind development, and achieve the goal of letting more enterprises avoid detours and save costs. So that China will become an independent country with technology and industrialization< At the same time, Qian Bozhang suggested that we should learn from foreign advanced experience, strengthen the close combination of production, study, research and application, establish relevant mechanisms, and raise the development of high-performance fiber industry to the national strategic height, so as to make China's carbon fiber industry develop rapidly and healthily< 1n recent years, foreign research and development of carbon fiber technology focus on improving performance and reducing cost. According to the demand of advanced composite market development, Toray company of Japan has decided to phase out T300 type carbon fiber and focus on developing carbon fiber varieties with tensile strength of 4000-5000mpa and price equivalent to T300. At the same time, due to the high cost performance of large tow carbon fiber, Toray company of Japan has also started to develop large tow carbon fiber, such as t6005, t7005, t700g, etc in addition, some enterprises attach importance to the research and development of environment-friendly recycled carbon fiber. Japan’s Toray, teiren and Mitsubishi Liyang plan to jointly produce recycled carbon fibers on a large scale to promote the recycling of high-strength and light-weight materials carbon fiber products are mostly used in special fields, and their service life and renewal cycle are strictly required. A large number of discarded carbon fiber products need to be treated. According to the estimation of Japan’s Mitsubishi Liyang, the global waste carbon fiber is about 10000 tons at present, and it can reach 20000 tons in 2010. With the expansion of carbon fiber production capacity and the extensive use of reinforced materials, the trend of environment-friendly is to be improved

Back to list