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arXiv · 1011.5451

A model for the degradation of polyimides due to oxidation

Satish Karra·K. R. Rajagopal
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Abstract

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.

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Satish Karra, K. R. Rajagopal. 2010-11-24. A model for the degradation of polyimides due to oxidation. https://doi.org/10.1007/s11043-011-9165-6

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