Development of Clay-based Film and Its Application to Gas Barrier Layers of Composite Tanks

Abstract

We have recently developed a new composite material, a clay-based film (CBF), for hydrogen tanks, with excellent hydrogen gas barrier properties and high durability. Preliminary test results showed that the hydrogen gas barrier properties of this material were approximately two to three orders of magnitude better than those of other polymer materials. We further investigated the relationship between the elongation and gas barrier properties of nanocomposite films composed of nylon and Li-exchanged smectite. As a result, we proposed films with a 70 % clay content, excellent in terms of both their elongation at break and gas barrier properties. Finally, multi-layered materials composed of carbon fiber reinforced plastic (CFRP) and CBF, and CFRP-based tanks were prepared using CBF. The developed material was shown to be highly applicable to lightweight hydrogen tanks for use in aircrafts, spacecrafts, and vehicles.