Thermo-oxidative stability of polyimides—I. Effect of prepolymer molecular weights

doi:10.1016/S0141-3910(96)00125-5

Polymer Degradation and Stability

Volume 58, Issues 1–2, 1997, Pages 11-14

https://doi.org/10.1016/S0141-3910(96)00125-5 Get rights and content

Abstract

Thermo-oxidative stability of polyimides under long-term isothermal exposure was studied. Model polyimides of various prepolymer molecular weights were synthesized and fabricated into graphite fiber reinforced composites. These composites were exposed to isothermal aging for up to 6000 h. Dynamic mechanical properties and weight loss measurements indicate that for polyimides prepared from prepolymers with low molecular weight, activation energy for oxidative degradation is decreased, resulting in higher total weight loss in long-term isothermal aging.

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Thermo-oxidative stability of polyimides—I. Effect of prepolymer molecular weights

Abstract

J. Compos. Mater.