Increased Durability of Astroquartz-Reinforced Polymer Matrix Composites

The development of AFR-PE-4 or RM-1100 polyimide composites has increased the high-temperature performance of military engine and airframe structures due to weight reduction. In order to take full advantage of these polyimide resin systems, Astroquartz® reinforced composites are needed for low-dielectric applications.  Current B-2 (Spirit) and B-21 (Raider) Northrop Grumman airframe components require composite structures that can provide long-term use under hot/wet environments.  AFR-PE-4/Astroquartz® composite materials have been selected for these structures where continuous service temperatures in excess of 316şC (600şF) are needed while retaining maximum physical properties. The main objective of the Phase II Small Business Innovative Research (SBIR) effort is to increase the environmental and thermal durability of Astroquartz®-Reinforced Polymer Matrix Composites (PMCs).  Maverick will focus on 6FDA-containing polyimide resin systems but will also include epoxy systems, when appropriate, such as Renegade Materials’ RM-2014-LDK low-dielectric prepreg material.  Chemical characterization and physical mechanical testing will be conducted to provide a thorough assessment of the current fiber-matrix interface in order to determine the root cause of mechanical property strength reduction when exposed to thermal and hot/wet conditioning. To this end, Maverick plans to work with Industry partners to provide the Air Force and their subcontractors with new Astroquartz® fiber coupling agents, finishes, and novel fabric surface treatments that will be tailored to the matrix resin.  By understanding the fiber-matrix degradation mechanism and then fixing the Astroquartz®/PMC interface, a robust prepreg material will be ready for qualification testing and transition into Department of Defense (DoD) platforms.