Characterization by ultra-micro indentation of an oxidized epoxy polymer: Correlation with the predictions of a kinetic model of oxidation

This study aims to understand better the influence of thermo-oxidation on the degradation of an epoxy resin used as the matrix of aeronautical composite laminates. Neat epoxy resin plates have been aged at 150 °C, under vacuum and ambient air. Using an instrumented ultra-micro indentation device, modifications of mechanical properties due to oxidation at elevated temperature are characterized through the measurements of elastic indentation modulus, Vickers hardness and indentation creep. By using a kinetic model of oxidation developed specifically for this epoxy resin, the local values of oxidation product concentration are calculated and correlated to experimental indentation measurements.