Ultra-High Temperature Elastomer Sealing Materials

This proposal addresses subtopic A1.01 Hyersonic/High Speed Technology - Seals and Thermal Barriers, specifically the listed interest in high temperature elastomeric materials for use at temperatures of 700? (371 ?) or greater. O-rings and other low leakage seals are frequently employed in a broad range of industries. These O-rings are frequently used to seal one environment from another especially in mechanical designs incorporating moving components at the interface. As supersonic and hypersonic vehicles increase in importance, materials capable of meeting their demanding applications are sought. Current high temperature elastomers encounter an upper temperature limit near 600? - a new material that surpasses this limitation may offer new utility. We propose an oligomeric pre-polymer strategy to synthesize tractable oligomers - a proven technique derivative of ATSPrsquo;s core chemical strategy for synthesis of high glass transition temperature aromatic thermosetting copolyester resins but redesigned to incorprate the flexible chains necessary to form an extremely thermally stable new elastomer -offering continuous performance at 700? (371?) and above, thus meeting the high-end requirements for hypersonic vehicles requested in the solicitation.The synthesized chemistry will be examined via nuclear magnetic resonance. Differential scanning calorimetry (DSC) will then be used to determine a rational thermal cure cycle. Thermal stability will be assessed through thermogravimetry. The combined process cycle will be developed through multiple iterative cycles while being evaluated through density determination and x-ray micro-computed tomography to determine void content and converge on the ideal density in the produced article. Produced articles will be examined in terms of their mechanical properties (including compression set and high temperature aging) as well as their glass transition. A single best-performing composition will be selected for a dynamic sealing test.