Natural outdoor and laboratory-controlled ageing of epoxy adhesives and CFRP laminates after four years of exposure

Ageing of epoxy adhesive and carbon fibre reinforced polymer (CFRP) laminate was addressed in this work. The specimens were exposed to laboratory-controlled (20 °C/55% RH, and water immersion at 20 °C) and outdoor (ageing mainly promoted by carbonation, freeze-thaws, airborne chlorides, and elevated temperatures) conditioning for up to four years. The results from tensile tests showed water immersion of the epoxy adhesive as the most severe exposure condition, yielding to 66% and 75% decrease in tensile strength and elastic modulus, respectively. In contrast, CFRP laminate generally improved the same mechanical properties in outdoor environments, the highest being 16.1% and 10.4%, respectively