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Kevlar inventor dies

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  • Kevlar inventor dies

    Stephanie Kwolek, inventor of Kevlar, dies at 90
    June 21, 2014

    Stephanie Kwolek, the DuPont Co. scientist whose research on polymers in the 1960s led to the creation of Kevlar, the light, super-strong synthetic fabric used in bulletproof vests and body armor credited with saving thousands of lives, has died. She was 90. During an achievement-laden career as a chemist at DuPont, Kwolek made her greatest mark with her 1965 work on a liquid crystal polymer that, dissolved in solvent and pressed through a device resembling a very fine colander, became a fiber five times stronger than steel, ounce for ounce.

    By 1964, she said, the DuPont lab “had made hundreds of polymers” — materials including nylon and spandex — “and had devised many new ways of making polymers, but there was still one block.” That was the lack of a breakthrough on so-called para-aramids, a type of polymer with rigid, rod-type molecules. After six months of experimenting with solvents on two of the polymers, she came up with an “extremely odd” chemical solution, one that was watery and cloudy rather than the typical viscous and transparent. She said she had to persuade the worker in charge of the lab’s spinneret to give it a try. “It formed very strong fibers and the stiffness was absolutely spectacular,” Kwolek recalled in a 1999 interview with the Pittsburgh Post-Gazette. “That’s when I said ‘Aha.’ I knew then and there it was an important discovery.” Fiber B as it was originally called was initially envisioned by DuPont as a lightweight means to strengthen tires.

    Patented as Kevlar, it found many industrial applications, most notably protecting soldiers and police officers from bullets and shrapnel. In the 1970s, it was adopted as the preferred material in bullet-resistant vests, replacing earlier alternatives such as nylon, fiberglass and boron carbide. The lives of more than 3,000 U.S. law-enforcement officers have been saved by vests and other body armor since the mid-1970s, according to the National Institute of Justice in Washington. “Not in a thousand years did I think the discovery of this liquid solution would save thousands of lives,” Kwolek said in 2003, according to USA Today.

    Rest in Blessed Peace