Mechanical Properties of a Hybrid Nanocomposite Under Room Temperature and Hot-Wet Environments

Abstract

A thermosetting epoxy resin was hybrid modified by addition of 9 wt% of rubber micro-particles and 10 wt% of silica nanoparticles. Glass fiber reinforced plastic (GFRP) composite laminates employing the unmodified (GFRP-neat) and the hybrid modified (GFRP-hybrid) epoxy matrix was fabricated. Mechanical properties viz., tension, compression, Interlaminar shear strength, and flexure, were determined for these GFRP composites in both room temperature (RT) and in hot-wet (HW) conditions. All the mechanical tests were conducted following their respective ASTM test standard specifications. Prior to testing, HW specimens were hygrothermally aged until moisture absorption saturation was attained. The GFRP-hybrid composite absorbs moisture at a higher rate and saturates with higher moisture content than that by GFRP-neat composite. The hybrid modification of epoxy matrix of GFRP composite alters the mechanical properties in RT by about +6 to −12 % and in HW conditions by about +3 to −9 %, depending on the specific property. The degradation of mechanical properties due to moisture varies from about 0 to 23 % in both GFRP composites. Dramatic improvement of over 160 % in fracture toughness and over 400 % in fatigue life of GFRP-hybrid composite reported earlier, appear to more than compensate for minor alterations in other mechanical properties of this material.