PPQ (Polyphenylquinoxaline) Resin Systems for High-Temperature Composite Materials

摘要

The subject program has been directed toward the development of the high-temperature resin system, polyphenylquinoxaline (PPQ), based on 3,3'-diaminobenzidine (DAB) and 4,4'-oxybisbenzil (OBB), through the use of a designed trifunctional crosslinking mechanism to provide a unified cured resin system with requisite thermomechanical capability as a laminating resin for end-use application in advanced weapons systems. Linear PPQ composites with Modmor-II carbon fiber reinforcement have displayed RT-flexural strengths as high as 301,300 psi, with residual thermoplasticity, however, at 700F. On the other hand, trifunctionally cured WRD X-361 PPQ homopolymer has demonstrated complete retention of RT-flexural performance in Modmor-II flat laminates at 700F. Each of these copolymer resin compositions could be readily fabricated into Modmor-II laminates exhibiting room temperature flexural strengths in excess of 200,000 psi. (Author)