Seawater durability of glass- and carbon-polymer composites

The effect of seawater immersion on the durability of glass- and carbon-fibre reinforced polymer composites was experimentally investigated. The materials studied were glass/polyester, carbon/polyester, glass/vinyl ester and carbon/vinyl ester composites used in marine structures. When immersed in seawater at a temperature of 30 °C for over two years, the composites experienced significant moisture absorption and suffered chemical degradation of the resin matrix and fibre/matrix interphase region. This degraded the flexural modulus and strength of the composites, although the mode I interlaminar fracture toughness was only marginally affected by immersion.