Abstract
Prepreg processing conditions of a polyimide (PI)-based GFRP and their effect on the tensile strength and modulus under low-pressure formation has been investigated. Formation below common pressure at 1.4MPa for PI-based FRP using an autoclave has been attempted. A wet-prepreg with the appropriate solvent retention abilities was prepared with an available poly amic-acid and glass-clothes. The preperg was heated at 373K for 2〜24h in a furnace. Four-ply-laminates on a direction of (0/90) were formed at a pressure of 0.7MPa using an autoclave. The tensile strength and modulus increase with increase in drying time of the prepreg with the fiber volume fraction of the GFRP was normalized to 60vol%. Even with the low-pressure formation, the equivalent tensile strength and elastic modulus of PI-based GFRP using the prepreg heated for periods over 10〜12h to 373K was shown beside that of common GFRP.
