Technologically1 valuable
ultrastable(超稳定的) glasses can be produced in days or hours with properties corresponding to those that have been
aged2 for thousands of years, computational and laboratory studies have confirmed. Aging makes for higher quality glassy materials because they have slowly evolved toward a more stable
molecular3 condition. This evolution can take thousands or millions of years, but manufacturers must work faster. Armed with a better understanding of how glasses age and evolve, researchers at the universities of Chicago and Wisconsin-Madison raise the possibility of designing a new class of materials at the molecular level via a vapor-deposition process.
"In attempts to work with aged glasses, for example, people have examined
amber4(琥珀)," said Juan de Pablo, UChicago's Liew Family Professor in Molecular Theory and Simulations. "Amber is a glass that has been aged millions of years, but you cannot engineer that material. You get what you get." de Pablo and Wisconsin co-authors Sadanand Singh and Mark Ediger report their findings in the latest issue of Nature Materials.
Ultrastable glasses could find potential applications in the production of stronger metals and in faster-acting
pharmaceuticals5. The latter may sound surprising, but drugs with the
amorphous6(无定形的) molecular structure of ultrastable glass could avoid crystallization during storage and be delivered more rapidly in the bloodstream than pharmaceuticals with a semi-crystalline structure. Amorphous metals, likewise, are better for high-impact applications than crystalline metals because of their greater strength.
The Nature Materials paper describes computer simulations that Singh, a doctoral student in chemical engineering at UW-Madison, carried out with de Pablo to follow-up some
intriguing7(有趣的) results from Ediger's laboratory.