TECHNOLOGY FOCUSAluminum Nano-Foam Will Make Vehicles Safer, Lighter VIENNA, AUSTRIA - Polystyrene foam, the protective agent inside bicycle helmets and automotive components, offers protection through the shock-absorbing ability of its millions of tiny, uniform closed-cell air bubbles. Essentially, when an object impacts the foam, the energy required to crush the walls of the foam cells slows the object down. But the use of polystyrene as the material of choice is about to be challenged.