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There's an old murder mystery trope about using an icicle as a stabbing weapon. Kill the victim, melt the weapon - no trace left behind.
Here's the sci-fi material science analogue - a rigid polymer that can be triggered to instantly decompose once you're done with it ...
I can foresee this stuff providing the basis for a lot of future Fortean reports ...
FULL STORY: https://www.sciencedaily.com/releases/2019/08/190826092302.htm
Here's the sci-fi material science analogue - a rigid polymer that can be triggered to instantly decompose once you're done with it ...
I can foresee this stuff providing the basis for a lot of future Fortean reports ...
Disappearing act: Device vanishes on command after military missions
A polymer that self-destructs? While once a fictional idea, new polymers now exist that are rugged enough to ferry packages or sensors into hostile territory and vaporize immediately upon a military mission's completion. The material has been made into a rigid-winged glider and a nylon-like parachute fabric for airborne delivery across distances of a hundred miles or more. It could also be used someday in building materials or environmental sensors.
The researchers will present their results today at the American Chemical Society (ACS) Fall 2019 National Meeting & Exposition.
"This is not the kind of thing that slowly degrades over a year, like the biodegradable plastics that consumers might be familiar with," says Paul Kohl, Ph.D., whose team developed the material. "This polymer disappears in an instant when you push a button to trigger an internal mechanism or the sun hits it." The disappearing polymers were developed for the Department of Defense, which is interested in deploying electronic sensors and delivery vehicles that leave no trace of their existence after use, thus avoiding discovery and alleviating the need for device recovery.
The key to making a polymer disappear, or break apart, is "ceiling temperature." Below the ceiling temperature, a polymer configuration is favored, but above that temperature, the polymer will break apart into its component monomers. Common polymers, like polystyrene, have a ceiling temperature above ambient temperature and are very stable. And even when they are warmed above their ceiling temperature, some of these materials can take a long time to decompose. For example, thousands of chemical bonds link all of the monomers together in polystyrene, and all of these bonds must be broken for the materials to decompose. But with low ceiling-temperature polymers, such as the cyclic ones Kohl is using, only one bond needs to break, and then all of the other bonds come apart, so the depolymerization happens quickly. The process can be initiated by a temperature spike from an outside or embedded source, or by a light-sensitive catalyst. ...
FULL STORY: https://www.sciencedaily.com/releases/2019/08/190826092302.htm