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Thermoplastic Materials Compatibility for Hydrogen Service

Project Code: 34250

Start date and planned duration: February 2021, 36 months


  • Develop test methodologies for evaluation of polymeric materials performance on exposure to hydrogen, thermal cycling, UV radiation and moisture.
  • Determine the effect of chosen degradation mechanisms on the micro- and macrostructure of the thermoplastics utilised in this study.
  • Characterise a number of selected polymers pre and post-exposure to determine the effect of hydrogen, thermal cycling, UV radiation and moisture individually and in a number of combinations.

Project Outline

The use of hydrogen as an energy resource is expected to play an important role in the transition to a low carbon economy. A full understanding of the effect of hydrogen on the behaviour of materials and joints in engineering structures is critical for the safe deployment of hydrogen infrastructure. A wide range of non-metallic materials is used in hydrogen production, transmission, distribution, delivery, and storage. Fibreglass, carbon-fibre, and aramid are commonly used in hydrogen storage tanks. High-density polyethylene (HDPE) and polyphenylene sulfide (PPS) are used as piping or tank liner materials. Polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), acetal, polyfluoroalkoxy (PFA), Buna-N, and fluoroelastomer (FKM) are some common sealing materials in valves.

This project will focus on the effect of hydrogen on thermoplastics that are used or considered for use in hydrogen service. In hydrogen service these materials may be exposed to pressures up to 15,000 psi (100 MPa) and temperatures from -70°C to +120°C, potentially under thermal cycling conditions. Little research has been carried out to explore the effects of such conditions. A number of representative thermoplastics will be selected for preliminary assessment of the effects of hydrogen, UV radiation, thermal cycling and moisture on their mechanical performance and microstructure.

Based on the outcomes of these individual tests, an appropriate, representative, testing regime will be proposed which combines elements of hydrogen, thermal cycling, UV radiation and moisture exposure into a single programme. The visual and mechanical properties of thermoplastics after this combined regime will be compared with specimens that have been subjected to only one of the tests.

The project will therefore include:

  • Hydrogen exposure.
  • Accelerated weathering.
  • Thermal cycling.
  • Moisture exposure.
  • Combinations of the above.

Industry Sectors


Surface Transport

Construction and Engineering

Polymers and Composites

 Benefits to Industry

The knowledge gained through a fundamental testing scheme of different environmental conditions will assist industry with material and process selection for products operating in a hydrogen environment. Availability of suitable test facilities and an agreed test regime will allow industry to carry out bespoke testing for the development and qualification of new products, leading to improved performance, reliability, safety and cost reduction.

For more information please email: