Tensile Properties of Fiber-Reinforced Plastic-Based Epoxy Prepregs Storable at Room Temperature

Carbon fiber-reinforced plastics (CFRPs) are widely used in various parts of the engineering field. Carbon fibers are among the materials with the highest specific strengths that are commonly applied in fiber-reinforced plastics. In many cases, epoxy resins are utilized as CFRP matrices, which can exhibit various physical properties, such as adhesiveness and heat resistance, depending on the curing agent. These resins are also attracting significant attention in the field of composite materials owing to their high strength and low weight. Composite materials containing epoxy resins are often stored in the form of prepregs at low temperatures (generally below 0 °C). If the mass-produced prepregs could be stored at room temperature, it would eliminate the need for bulky equipment (such as freezers) and considerably reduce manufacturing costs and environmental burden (including energy consumption). Consequently, many currently used transportation methods and conventional manufacturing processes would be changed dramatically. Thus, the purpose of this study is to investigate the possibility of using a pre-cured resin storable at room temperature as a CFRP matrix material.