What is special engineering plastics
Special engineering plastics refer to some plastics with more excellent and unique properties, which have not been industrialized in large scale or produced in small scale, and have relatively narrow applications, such as polyphenylene sulfide (PPS), polyimide (PI), polysulfone (PSF), polyether ketone (PEK), liquid crystal polymer (LCP), etc.
Characteristics of special engineering plastics
Compared with general engineering plastics, special engineering plastics have more superior and unique properties. The long-term service temperature can exceed 177 ° C. At present, it has not been mass produced. According to the stage division, special engineering plastics are defined as the third generation of polymer materials after general plastics and engineering plastics. Special engineering plastics have the following characteristics:
(1) Exceptional stability and performance beyond traditional polymers when exposed to certain harsh environments.
(2) It is mainly made of non elastic thermoplastic materials, which are mainly processed by extrusion or injection molding.
(3) Research, development and promotion costs are high, and the price is high. The high performance and high cost of special engineering plastics coexist, which makes its cost performance ratio not superior to that of general engineering plastics. For many years, the application of special engineering plastics has been concentrated in military, aerospace and other fields. In recent years, it has been gradually transferred to the civil fields such as electronics, electricity and automobiles. In addition, the price of special engineering plastics is usually 10 dollars/kg, and some varieties even reach 40~100 dollars/kg, while the price of general engineering plastics is generally 4~7 dollars/kg.
At present, several kinds of materials have the characteristics of special engineering plastics: aromatic polyketones [PEEK and PEKK]; High performance polyamide, liquid crystal polymer, polyaryl ester, poly (cyclohexyl dimethyl terephthalate), polyphenylene sulfide (PPS), sulfone polymer, thermoplastic PI, etc.
Application of special engineering plastics
A typical feature of special engineering plastics is that the production volume is relatively small and the use is special. This kind of material zui was originally born to meet the needs of national defense forces or human scientific exploration. At present, its application is moving towards civilian use.
1. Aerospace
2. Electronic information field
3. Medical field
4. Energy field