Investigation into features of fracture toughness of a transparent E-glass fiber reinforced polyester composites at extreme temperatures.

In recent years, several investigators have made efforts to satisfy industrial and transportation demands with respect to high mechanical properties. Moreover, the transparent composites are needed for automotive and aircraft applications. Thus, developing more efficient and advanced transparent composite techniques has recently got more attention but seldom studied in harsh conditions. The main goal of the present study is to investigate the impact of exposing a transparent polyester composite to different temperatures ranging from high to very low (60, room temperature, 0, -30, -60, and -80 °C) and 50% humidity. The study of the effect on both fibers and matrix upon exposure to the different conditions and the composite represents an attempt towards climate resistance. In this research, fracture toughness of E-glass fiber reinforced unsaturated polyester composite at high and very low temperatures and humid environments were investigated. The investigation deals with the characterization of fracture strength properties according to the ASTM standards and mechanism of fracture by scanning electron microscopy. The transparent composite was fabricated from the unsaturated polyester matrix and E-glass fibers. Using of E-glass fiber for reinforcing with 15% volume percent for preparation of the transparent composite exhibits fracture toughness at very low temperatures. It was also noted that the technique of giving an excellent transparent polyester composite can be utilized confidently to architect and aircraft structures.