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.