Elevated temperature mechanical behavior of nano Al2O3 embedded interpenetrating polymer network/glass fiber composites

Two methods of enhancing the mechanical performance of glass fiber reinforced polymer (GFRP) composites, namely the formation of an interpenetrating polymer network (IPN) of two thermoset polymers (epoxy and vinyl ester) and the addition of nanofillers (nano Al2O3) have been implemented simultaneously. The content of nano Al2O3 (0.1, 0.4, and 0.7 wt% of the polymer matrix) in the glass fiber reinforced epoxy‐vinyl ester IPN (GEVIPN) composite significantly affected its mechanical performance. Incorporation of 0.1 wt% nano Al2O3 in GEVIPN composite exhibited 17.69% and 27.64% improvement in flexural strength and toughness, respectively. Additionally, when the composites were subjected to elevated temperature testing, their mechanical performance was drastically affected. However, the test results revealed that nano Al2O3/GEVIPN composites possessed significantly improved mechanical degradation resistance at elevated temperatures. This new composite material could be utilized as structural materials in the civil, automotive, and marine industries. Dynamic mechanical thermal analysis was performed to assess the composites' thermomechanical behavior. Fractography analysis of tested samples revealed the underlying phenomena, which dictate the mechanical performance at each testing temperature. A constitutive deformation model assessed the reliability of this new material at ambient and elevated test temperatures.