Special engineering plastics are a kind of engineering plastics with high comprehensive properties and long-term service temperature above 150 ℃. Internationally, special engineering plastics originated in the late 1960s. From polyimide in the 1960s to peek in the early 1980s, large companies in Europe and the United States have carried out a lot of research and development on special engineering plastics. At present, more than ten kinds of varieties with application value and industrialization have been formed, which are widely used in electronics, automobile, aerospace, etc Precision instruments and other high-tech industries.