Word: teflon
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...ball valve is rougher on blood cells than nature's leaflet valves, so surgeons at the University of Wisconsin have developed butterfly valves of Teflon that come closer to the original in design. The demands on the plastic in such valves are tremendous: the leaflets must bend back and forth 40 million times a year. But so far, 39 patients have had them installed as replacements for aortic or mitral valves, and they are still working after as long as 20 months...
...outer part of the transplanted human cornea can be left in place, cloudy as it is. Dr. Stone removes most of the thickness in the center, and sets in place a narrow, artificial cornea made of polymethyl methacrylate surrounded by a Teflon skirt (see diagram). The very center of the device is threaded so that it can be moved in or out to adjust its optical characteristics. And if the patient should need further major surgery, the plug can be unscrewed all the way, giving the surgeon direct access to the inside of the eyeball. As for the inside, where...
...family's clothes are probably dry-cleaned with Du Pont Perclene, waterproofed with Zelan, bleached with Oxone. Their food comes in packages that are glued together with Elvacet and wrapped in Mylar, stored in a refrigerator cooled by Freon and cooked on a greaseless griddle coated with Teflon. Their car may be finished with Lucite, their furniture lacquered with...
1/20,000th of an Inch. Silicone rubber is one of the most permeable substances (60 times more so than Teflon film), and General Electric Researcher Walter L. Robb, 36, had long known that it could be made to act like a membrane. Two years ago, Robb hit on a way to stretch the rubber into sheets 1/20,000th of an inch thick, set about trying to devise a way to eliminate the tiny holes that somehow showed up in each square foot of film. His solution was simple: since the probability of two holes being in the same spot...
...fluorine atoms in a molecule of Teflon form such a tightly bonded structure around the substance's carbon atoms that the molecules of other materials that touch Teflon have little opportunity to stick...