The preparation method of the film is as follows: Casting polyamic acid solution into a film, stretching, and then imidizing at high temperature. The film is yellow and transparent, and the relative density is 1.39~1.45. It has excellent high temperature resistance, radiation resistance, chemical corrosion resistance and electrical insulation performance. It can be used in air at 250 to 280 ° C for a long time. The glass transition temperatures were 280 ° C (upilex R), 385 ° C (Kapton) and above 500 ° C (upilex s), respectively. The tensile strength is 200MPa at 20 ° C and greater than 100MPa at 200 ° C. It is particularly suitable for use as a flexible printed circuit board substrate and various high temperature resistant electrical and electrical insulation materials.
physical property
Thermosetting polyimide has excellent thermal stability, chemical resistance and mechanical properties, usually orange. The bending strength of graphite or glass fiber reinforced polyimide can reach 345mpa and the bending modulus can reach 20GPa. Thermosetting polyimide has small creep and high tensile strength. Polyimide can be used in a wide range of temperatures, ranging from minus 100 ℃ to twoorthree Baidu.
chemical property
Polyimide has chemical stability. Polyimide does not require the addition of flame retardants to prevent combustion. Common polyimides are resistant to chemical solvents, such as hydrocarbons, esters, ethers, alcohols, and chlorofluorocarbons. They are also resistant to weak acids, but are not recommended for use in environments with strong bases and inorganic acids. Some polyimides, such as CP1 and Corin XLS, are soluble in solvents, which helps to develop their applications in spraying and low-temperature crosslinking.
