| 摘要 |
PURPOSE: To increase a thermal capacity by sealing a layup of preprgs formed of a carbon fiber reinforcing agent and a specific amount of polyimide precursor monomer, sucking a content, heating a bag at specific pressure and temperature, thereby enhancing durability and performing a multiple use. CONSTITUTION: A layup of prepregs containing a mixture of about 95% of p-phenylenediamine of a stoichometrical amount for obtaining 35 to 45 vol% of a polyimide and a diamine of its residue of m-phenylenediamine and 2,2- bis-(3',4'-dicarboxyphenyl) hexafluoropropane in a carbon fiber reinforcing agent and prepreg is formed. The layup is sealed in a vacuum bag, and a content of the bag is vacuum sucked. And, a pressure of about 180 lbs/square inch is applied to the bag. Then, the layup is heated to about 250 to 400 deg. F, a deposit is cooled while releasing the pressure and vacuum. And, in vacuum for removing a polymer by-product, it is heated to 700 to 725 deg. F at a speed of 1 to 3 deg. F/min in an oven until Tg of a composite mold arrives at 730 deg. F. |
