Special feature: Getting a handle on H2

The rubber industry is at the forefront of developments to harness the power of hydrogen, as evidenced by range of projects among manufacturing and R&D specialists in this fast-emerging industry.

In the field of research, Fraunhofer Institute for Structural Durability and System Reliability LBF is seeking new industrial partners for a project to develop elastomers for hydrogen sealing & transfer applications.

Project Elastolox aims to find elastomeric alternatives to high-resistance fluoropolymers, which could be impacted by proposed PFAS regulations in the EU, the Darmstadt, Germany-based institute announced in August.

The project will particularly focus on polymers offering resistance to the “extreme” oxidative-alkaline conditions that occur in electrolysers used for hydrogen technology.

“Alternative substitute materials must be identified and evaluated in terms of their resistance in alkaline environments and oxygen atmospheres and their mechanical properties,” said Fraunhofer LBF.

In particular, it said, there is “a lack of information” on the behaviour of most polymer materials, including elastomers, under long-term exposure to the aggressive media found in these applications.

“Media conditions are diverse and include gases such as hydrogen and oxygen or liquids such as coolants, product water, acidic or basic electrolytes,” it explained.

For the research work, Fraunhofer LBF said it will use “tailor-made methods” to characterise and understand the media impact on polymers used in hydrogen technology.

Furthermore, the research will encompass a wide variety of possible mechanical stresses that can occur under different loading speeds and frequencies.

To be based at Fraunhofer’s hydrogen performance centre – GreenMat4H2 – the project will also cover the analysis and development of ageing models and simulation methods for polymer materials.

Compound interest

Meanwhile, Trelleborg, Sweden-based Trelleborg has developed a range of sealing compounds for the containment and transfer of hydrogen during production, transport and storage, and end-use.

The R&D programme for the 20 H2Pro products involved the introduction of “proprietary, next-level” testing regimes to validate materials for real-world hydrogen applications, said a group announcement.

The materials, it stated, are “suitable for high pressures, low temperatures, and resist permeation, making them better able to withstand rapid gas decompression (RGD), while also demonstrating excellent wear and extrusion properties.”

As the smallest and lightest molecule, hydrogen is difficult and complex to seal, said Trelleborg’s global energy segment director James Simpson, adding that a lack of relevant industry standards to validate the new materials was a major challenge.

“Some in the nascent hydrogen industry rely on standards used typically for high-pressure gasses in the oil & gas sector, but these are often unsuitable for replicating real-world hydrogen application conditions,” explained Simpson.

Therefore, he said, Trelleborg “developed proprietary testing protocols that replicate real-world hydrogen applications”, including dedicated standards for hydrogen permeation, endurance-validation and hydrogen-compatibility, including the ability to withstand RGD.

According to Trelleborg, its extended H2Pro range “meets the diverse requirements of real-world hydrogen applications” with elastomers including EPDM, FKM, silicones and polyurethanes, as well as engineering plastics and metals.

In Nagoya City, Japan, Sumitomo Riko Co. has stepped up its activities around the development and production of components for hydrogen-powered vehicles.

In partnership with an alliance of Japanese automotive companies, called Commercial Japan Partnership Technologies, the company is now producing anti-vibration rubber, hoses, and other products for ‘small fuel cell trucks’.

According to Sumitomo Riko, it has developed an antivibration rubber mount for securing the hydrogen tank to the body part of the trucks. The mount is designed to “stably” support the hydrogen tank and contribute to reducing vibration from the tank valve.

The manufacturer is also supplying rubber seal gaskets designed to prevent leakage of hydrogen, oxygen, and water from fuel-cell stack components. The gaskets are designed to ensure effective sealing of each component across a wide temperature range, from sub-zero to over 100°C.