Description: Hydrogen is used in a broad range of applications such as petroleum refining, NH3 and biofuels production, hydrogen fuel cell electric vehicles (FCEVs), as well as for energy storage through injection into natural gas pipelines. Use of hydrogen results in the need for innovative durable sealing materials for extreme use conditions that exhibit low hydrogen permeability and high durability in dynamic sealing. In particular, proposals investigating materials at high pressure (>875 bar) and extreme temperatures (>475K and < 33K) and polymeric materials for use as seals in extreme environmental conditions including high pressure (up to 130 MPa) and variable temperatures (-50 < T >200 oC) are needed for hydrogen applications. Applications include dynamic compressors seals, valve seats and fiber reinforced polymer pipeline and tank liners. In particular the seals currently used in hydrogen compressors have a lifetime of 2,000-8,000 hours. The range in the durability of the seals is largely due to the duty cycle and operating temperature of the compressors. Additionally some seal materials have been found to be susceptible to hydrogen permeation while under high pressure and subsequent blistering on depressurization. This failure mode is not the same as the rupture seen during explosive decompression. Materials development is needed for dynamic compressor seals which can contain hydrogen at pressures of 1,320 bar (1.5x the application working pressure of 875 bar) while operating for >18,000 hours under cyclic pressure loading at 200C . Materials developed would also be applicable to other balance of plant components such as the dispenser hoses, valve seals, and high pressure storage tank liners.
Phase I must include identification and preliminary testing of polymers with potential suitability for 18,000 hours of use in hydrogen at temperatures of 200C and pressures of 1,320 bar (1.5x the application working pressure of 875 bar) in dynamic sealing applications. Results of phase I should include a report summarizing the findings and suggesting modifications to the polymers to improve their performance. Phase II would include the development and in-depth characterization of the selected or modified polymers. Research should include a scientific exploration of the mechanisms of failure in cyclic high pressure and high temperature hydrogen environments of the application. Characterization should also include the hydrogen permeation, hydrogen uptake, creep, and other degradation mechanisms needed to provide a better understanding of the durability, mechanical stability, and service life of a material used in severe or extreme service.