Testing for the Effects of Pressurized Hydrogen on Polymeric Elastomers

This work demonstrated an experimental testing process to quantitatively test for the effects of pressurized hydrogen on polymeric materials. It was shown that some o-ring materials are susceptible to deleterious property changes. A high-pressure hydrogen testing system with a window was fabricated and was used to soak elastomeric o-rings in hydrogen at temperatures from 22 to 40°C and 13.8 to 16.5 MPa for up to 96 hours. Next, the o-rings were observed through the window during the depressurization. Finally, the o-rings were characterized before and after hydrogen exposure for hardness, weight, tensile strength, and ultimate elongation. The data showed the following four quantitative trends 1) durometer decreased up to 14%, 2) weight was mostly unchanged, 3) tensile strength decreased up to 35%, 4) ultimate elongation decreased up to 55%.