To make clay strong, just add glue.
Nanotechnology promises to deliver materials that will possess, on a large scale, the exceptional mechanical properties of tiny particles such as carbon nanotubes or the mineral grains that constitute clay. But because a chain is only as strong as its weakest link, it's crucial that in materials made of strong building blocks, those blocks stick together robustly.
Nicholas Kotov and his collaborators at the University of Michigan in Ann Arbor have created high-strength films by linking clay particles and polymers. The researchers dissolved clay in water, freeing its component particles—nanometer-thick flakes composed of aluminum, oxygen, and silicon atoms. They let the sheets deposit onto a glass surface, alternating them with layers of the polymer polyvinyl alcohol, "a chemical cousin of the glue that you used at school," as Kotov describes it.