Thermal, oxidative and radiation stability of polyimides I. Bismaleimidoethane and different diamine-based polyimides

The syntheses of 1,2-ethane-bis-maleamidoacid, N,N'-1,2-bis-maleimidoethane (BME), and polyimide resins based on BME and four different diamines are g iven. The thermal and thermooxidative stability of the resins was studied b y thermogravimetry (TG) following parameters such as temperatures for defin ed weight loss and initial decomposition rate, i.e. shape of TG and first d erivative TG curves. Samples have been irradiated and their radiation stabi lity evaluated on the basis of the thermal and thermooxidative behavior of the irradiated samples. The thermal behaviors have been analyzed and the re sin based on the diamine with the benzene ring showed the best thermal stab ility. Radiation in the applied dose range showed an increase of thermal st ability. (C) 2000 Elsevier Science Ltd. All rights reserved.