Mechanical behavior of multiaxial reinforced composites sun light degraded

We have studied the mechanical behavior of polyester composites reinforced with glass fiber cloth, taffeta, or multiaxial 2D which is degraded under sun light conditions. The elaboration procedure was the hand contact method, which is supposed to be the worst; so it could represent the most unfavorable conditions. Eight reinforced sheets were disposed asymmetrically. Laminates were exposed to a UV-visible IR light source, up to 7000 hr. A mathematic correlation has been obtained on the mechanical properties. The degradation follows a damped exponential model. We studied the Influence of kind of resin, reinforcement distribution, and cure conditions. Laminates done with resins with higher reactivity shows better behavior against fracture and higher plasticity. The cure heat treatment increases the mechanical properties.