Additive Manufacturing of Continuous Carbon Fiber Reinforced Phthalonitriles for Thermal Protection

The KAI-UD team proposes to develop a methodology to manufacture continuous carbon fiber-reinforced high-temperature thermoset composite TPS via state-of-the-art (SOTA) additive manufacturing technique. In this proposal, commercially available phthalonitrile (PN) thermoset resin developed by NRL will be used for our Phase I study. As a class of high-temperature high-performance thermosetting polymer, PN resins exhibit many excellent properties including high thermal and oxidative stability, flame retardance, the absence of a Tg before the thermal decomposition temperature, as well as water and chemical resistance. Dr. Kun Fursquo;s lab at the University of Delaware (UD) has recently developed an additive manufacturing technique, called localized in-plane thermal assisted (LITA) 3D printer, which can print continuous carbon fiber-reinforced thermoset composites. The LITA 3D printing technique overcomes the challenge of traditional 3D printing techniques with high volume fractions of carbon fibers, reduced the fiber misalignment, and minimized the void content. We have high confidence that the combination of the high-temperature resin with the newly-developed LITA 3D printing technique, these new carbon fiber-reinforced thermoset composites will exhibit excellent ablation resistance, insulative and mechanical properties.The objective for this Phase I project to develop 3D printable continuous carbon fiber-reinforced PN resin composites with low porosity and fiber volume ratios up to 60%. The developed TPS material must be 3D printable to produce a significantly less labor-intensive operation than the current SOTA TPS manufacturing while maintaining the critically rigorous manufacturing standards associated with space flight engineering.