Properties of Epoxy Based Hybrid Composites

Abstract

Epoxy resins have very important chemical and mechanical properties, however they have a small elongation at break, poor impact strength and resistance to crack propagation i.e. they exhibit a brittle behaviour. This study investigates the effects of inorganic and polymeric modifiers on the fracture toughness, thermal properties and creep modulus of epoxy resin. The obtained results show that a specific amount of kaolin and polyesters (Desmophen 1100 and Desmophen 1200) improved maximally the impact strength, the critical stress intensity factor as well as the flexural strength. As expected, creep modulus increased with addition of kaolin and decreased with polyesters modifiers. Similar results to those were obtained with the deflection temperature under load. Moreover, the results confirmed that hybrid composites had higher fracture toughness than unmodified epoxy resins or composites containing one modifier. No synergism effect was observed with the hybrid composites mechanical properties.