In this NBC News Learn video, part of a series on “Chance Discoveries” in chemistry, veteran NBC News war correspondent Richard Engel tells the story of lab work done in 1965 by DuPont chemist Stephanie Kwolek that unexpectedly produced Kevlar, a lightweight fiber five times stronger than steel. Kevlar fibers can be spun into anti-ballistic, shrapnel-resistant material for protective body armor worn by police forces, military troops and those in combat zones, including Engel himself.
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