A BRIEF HISTORY OF CARBON FIBER: starting with carbon fiber technology in Japan

In the late 1950s and early 1970s, Japanese scientists developed polyacrylonitrile and pitch based carbon fiber technologies, which Japanese companies effectively commercialized and continued to hold a global leadership position for nearly 50 years. As a follower, we need to look at the path of growth of the front-runner to discover some useful lessons.

1. people, institutions and events that have played a key role in the technological breakthrough of PAN-based carbon fibers.

In terms of time sequence, eight major factors played an important role in the early success of PAN-based carbon fiber technology research and industrial construction in Japan, a newspaper newsletter, a young scientist, a patent for an invention, a research institute, an American Visitor, a group of innovative companies, a business opportunity, and a national standard.

1.1.A newspaper newsletter

On May 29,1959, the “overseas technology column” of the Nikkan Kogyo Shimbun published a brief news about the research progress of man-made silk-based Carbon fibers of US National Carbon Company. SEE FIGURE 1. The content of the news is: The National Carbon Materials Company has successfully researched the technology of producing graphite fiber from Rayon by 3000 heat treatment. The obtained graphite fiber has a carbon content of 99.98% , and is resistant to high temperature, oxidation, chemical corrosion and thermal shock, and the small heat Neutron capture, which can be processed into felt, cloth, rope and other products, it can also be used as a heat resistant filler for plastics and Refractory, thermoelectric components, tube barriers, infrared radiators, self lubricating gaskets, filaments, and heat resistant conveyor belts. It was this short message that opened the prelude to Japan’s carbon fiber technology research.

1.2. a young scientist

Dr. Akio Shindo, a 33-year-old young scientist (1926 -- 2016) , happened upon the news and became interested in carbon fiber. He graduated from Hiroshima University in 1951, and in 1952 joined ŌSAKA’s Government Industrial Research Institute, part of Ministry of Economy, Trade and Industry (Japan)’s Ministry of International Trade and Industry (Miti) , eNGAGED IN HIGH-DENSITY CARBON PRODUCTS AND CARBON MATERIALS TECHNOLOGY FOR NUCLEAR REACTORS AT CARBON MATERIALS RESEARCH LAB 1.

In the 1950s, you couldn’t make carbon or graphite self-forming products, you could only make molded products. Because graphite melts at nearly 4,000 pressures, it can not be melt spun into fibers, which can only be made by carbonizing organic fibers, as is the case with other carbon materials. The organic fibers used for carbonization are called carbon fiber precursors. In order to find suitable precursor, from 1966 to 1976, scientists have studied more than 20 organic compounds, including phenolic, phenol Formaldehyde, furan resins, polynaphthylacetic acid, polyacrylether, polyamide, polybenzene, polyacetylene, polyimide, polybenzimidazole, polybenzimidazole cationic salts, polytriazole, modified polyethylene, modified polypropylene, polyvinyl chloride, polymethyl vinyl ketone, polyvinyl alcohol and polyvinyl acetate, but they have no commercial value as carbon fiber precursors. The Mechanical Properties of rayon-based carbon fibers are too low, and the carbon conversion is only about 20% .

Only a month after reading the newsletter, Akio INARI launched his research. In order to find the right precursor, he went to the department store and collected all kinds of fabrics. The cloth is then heat treated in nitrogen 1000 and its variation is observed using a quartz differential thermal balance (Fig. 2)[3] . Among the materials collected, only the cloth woven by the American dupont company Orlon Pan Fiber, after heat treatment, can still exist in the form of black fluff ball, this is the first PAN-based carbon fiber [4] . In the process of heat treatment, the nitrogen and hydrogen in the molecule were converted into ammonia and hydrocyanic acid, and the carbonized composition contained a high proportion of carbon, which maintained the fiber shape and had good strength, modulus and heat resistance After further heat treatment at higher temperature, fibrous graphite can be obtained. He also found that higher quality PAN-based carbon fibers can be obtained by heat treatment in air, with a carbon conversion of 50% to 60% . This has laid the technical foundation for the industrialization of carbon fiber.