Modeling the pressure dependent solubility in a thermoset resin for simulating pressure accelerated thermo-oxidation tests

• Approach for modeling high pressure thermo-oxidative conditioning (epoxy resin).
• Correlation between chemical and mechanical properties (accelerated ageing).
• Accelerated thermo-oxidation tests and EIT measures for samples tested up to 8 bars.
• Oxygen pressure as a pertinent accelerating parameter for thermo-oxidation degradation.

This paper presents an approach for modeling high pressure thermo-oxidative conditioning, for an epoxy resin material.A coupled reaction–diffusion chemical “mechanistic” model of thermo-oxidation with classical boundary conditions, successfully applied for samples aged under air at atmospheric pressure but failing at high pressures, has been enhanced by formulating a new nonlinear sorption law, correlated with the results of Elastic Indentation modulus (EIT) measures at 5 bars of pure oxygen, and validated for pressures up to 8 bars of pure oxygen.The approach allows justifying the employment of the oxygen pressure as a pertinent accelerating parameter for thermo-oxidation degradation: moreover the proposed model can be employed for the design and the optimization of accelerated thermo-oxidation tests.