Français
1. Preparation
1.1 Polyimide synthesis
Linear polyimides are synthesized by polycondensation of a dianhydride and a diamine in a two-step process, illustrated in figure 1 (preparation of the polyimide PMDA-ODA, analogous to DuPont's Kapton). The high reactivity of amines towards anhydrides enables an amic polyacid to be obtained in the first step by opening the anhydride ring. Heating in the presence of a catalyst enables cyclization with elimination of water, and the polyimide is obtained. In addition to cyclization, heating to around 300°C removes the polycondensation water and solvent.
The Ultimate Scientific and Technical Reference
This article is included in
Plastics and composites
This offer includes:
Knowledge Base
Updated and enriched with articles validated by our scientific committees
Services
A set of exclusive tools to complement the resources
Practical Path
Operational and didactic, to guarantee the acquisition of transversal skills
Doc & Quiz
Interactive articles with quizzes, for constructive reading
Preparation
Polyimide properties
Economic data
Because of their high price (around thirty times that of polyamides), the market for condensation polyimides is still limited to high-performance applications, and tonnages consumed remain low, even though this market is growing steadily.
The largest market for polyimides is in the United States, with the fastest-growing sectors being film and fibers.
In Europe, the key sectors...
Bibliography
- - On pourra trouver, sur les sites internet des différents producteurs, dont les adresses sont données ci-dessous, des notices documentaires assez détaillées, d'où ont été extraites la plupart des données chiffrées du dossier ainsi que certaines figures.
References
Main producers
(non-exhaustive list)
Du Pont de Nemours : http://www.dupont.com/
Kapton : films
Vespel: parts and semi-finished products
Pyralin: photosensitive polymers
PIQ: precursor solutions
The Ultimate Scientific and Technical Reference
