Ageing of pultruded glass fibre reinforced polymer composites exposed to combined environmental agents

This paper presents an experimental research on the durability of pultruded Glass Fibre Reinforced Polymer (GFRP) composites applied in building construction. Three different matrices have been used with E-glass fibres: isophthalic polyester, orthophthalic polyester and vinylester. The degradation of the mechanical and aesthetical performance of the composites has been monitored through a process of accelerated artificial ageing in a climatic chamber, simulating the combined effect of high temperature, freeze–thaw cycles, moisture and ultraviolet (UV) radiation. Tensile, bending and interlinear shear strength tests have been performed to measure the variation of some mechanical properties during six months of artificial exposition. A consistent reduction of the mechanical performance has been observed. Aesthetical appearance has been affected as well both in terms of loss of lightness and colour variation. The data collected have been compared to those after one year of natural ageing in external atmosphere. It has been observed that the considered artificial ageing produces a higher degradation of some mechanical properties if compared to the natural ageing in north Italy climate, accelerating the effects of the environment.