Durability of Flax FRPs Exposed to Accelerated Environmental Conditions

Abstract

It is well known that synthetic fiber reinforcements, such as glass fibers, elevate the mechanical properties of polymer materials. Considering the synthetic material’s renewability challenges, natural fibers, such as flax can provide promising mechanical behavior as a more renewable resource. However, the durability of natural fibers against moisture and other environmental conditions is not well-known. In this paper, aggressive accelerated tests were conducted in order to investigate the durability of flax fiber-reinforced polymer (FRP) composites in comparison to glass FRPs. The initial process was making FRP sheets out of two layers of fabrics and vinyl-ester resin; and then cutting them into dumbbell-shaped specimens for tensile test. The specimens were put under three different environmental conditions namely water, salt water, and alkaline solutions. Some specimens were kept in an air dry condition as control specimens. The temperature of the solutions was controlled at 20, 50, and 60 C. The durability testing was conducted at 500, 1000, 2000, and 3000 hours exposure. The results show that flax FRPs have similar and even slightly better durability performance in terms of tensile strength retention percentage in comparison to glass FRPs.