Phthalonitrile-carbon fiber composites produced by vacuum infusion process

High-temperature carbon fiber-reinforced plastics based on phthalonitrile resins are obtained for the first time by vacuum infusion process. For this purpose, formulations based on low-melting bis(3-(3,4-dicyanophenoxy) phenyl) phenyl phosphate monomer in combination with 1,3-bis(3,4-dicyanophenoxy) benzene and 4-[3-(prop-2-yn-1-yloxy) phenoxy] benzene-1,2-dicarbonitrile were developed. Resin viscosities eta <= 600 mPa.s were suitable for VIP and at the same time the thermal and mechanical properties of the cured matrices were in high level featured to phthalonitriles (HDT >= 420 degrees C, E >= 5.1 GPa). CFRP samples were manufactured by vacuum infusion process with carbon fabric and demonstrated thermal stability over 400 degrees C and a change of mechanical properties by less than 10% at 300 degrees C. Present results sufficiently extend the application field of phthalonitriles as matrices for complex-shape high temperature composite parts in aerospace or high-temperature composite tooling for PEEK-like thermoplastics processing.