  Polyimides, due to their superior mechanical behavior at high temperatures,
are used in a variety of applications that include aerospace, automobile and
electronic packaging industries, as matrices for composites, as adhesives etc.
In this paper, we extend our previous model in [S. Karra, K. R. Rajagopal,
Modeling the non-linear viscoelastic response of high temperature polyimides,
Mechanics of Materials, In press, doi:10.1016/j.mechmat.2010.09.006], to
include oxidative degradation of these high temperature polyimides. Appropriate
forms for the Helmholtz potential and the rate of dissipation are chosen to
describe the degradation. The results for a specific boundary value problem,
using our model compares well with the experimental creep data for PMR-15 resin
that is aged in air.
