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 quant itative methods. Weight loss experiments were performed on carbon fiber/epo xy laminates under both isothermal and dynamic conditions using various fib er directions and lay-up sequences in the laminate specimens. Weight loss r ates 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 lo ss 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. (C) 2000 Elsevier Science Ltd. All right s reserved.