Carbon fibers can be obtained by carbonization of polyacrylonitrile fibers, asphalt fibers, viscose fibers or phenolic fibers, respectively. The most common carbon fibers used are polyacrylonitrile carbon fiber and pitch carbon fiber. The production of carbon fiber includes four processes of fiber spinning, heat stabilization (pre-oxidation), carbonization, and graphitization. The accompanying chemical changes include dehydrogenation, cyclization, pre-oxidation, oxidation, and deoxidation.
The carbon fiber with high mechanical properties obtained from viscose fiber must be graphitized by high temperature, the carbonization yield is low, the technical difficulty is large, the equipment is complicated, the product is mainly used for ablation resistant material and heat insulating material; the carbon fiber is made from asphalt. The raw materials are abundant and the carbonization yield is high. However, due to the complicated preparation of raw materials and low product performance, it has not been developed on a large scale. The high-performance carbon fiber can be obtained from the polyacrylonitrile fiber precursor, and the production process is simpler than other methods. Excellent performance, developed well in the carbon fiber industry since the 1960s.