Kapton

Kapton is a polyimide film developed by DuPont which can remain stable in a wide range of temperatures, from −273 to +400 °C (−459 – 752 °F / 0 – 673 K). Kapton is used in, among other things, flexible printed circuits (flexible electronics) and thermal micrometeoroid garments, the outside layer of space suits.

The chemical name for Kapton K and HN is poly(4,4'-oxydiphenylene-pyromellitimide). It is produced from the condensation of pyromellitic dianhydride and 4,4'-oxydiphenylamine. Kapton synthesis is an example of the use of a dianhydride in step polymerization. The intermediate polymer, known as a "poly(amic acid)," is soluble because of strong hydrogen bonds to the polar solvents usually employed in the reaction. The ring closure is carried out at high temperatures (200–300 °C, 473–573 K).