Investigation of thermal degradation behavior of polymeric composites: Prediction of thermal cycling effect from isothermal data

Composite degradation was investigated by measuring weight loss using quantitative methods. Weight loss experiments were performed on carbon fiber/epoxy laminates under both isothermal and dynamic conditions using various fiber directions and lay-up sequences in the laminate specimens. Weight loss rates were specimen geometry dependent, implying an anisotropic degradation behavior. A model was used to describe the sample weight loss at isothermal temperatures. The model was also used in combination with time-temperature superposition theory to predict the effect of thermal cycling on weight loss to understand the long-term properties of composites. It was found that the model successfully quantified the thermal degradation behavior observed under thermal cycling conditions.