Stephanie Kwolek, Pioneering Inventor of Kevlar, Dies at 90
Chemist Stephanie Kwolek at work in DuPont's Pioneering Research Lab in 1967.
Credit: Courtesy of DuPont

Scientist Stephanie Kwolek, who invented the ultra-tough synthetic fibers used in Kevlar body armor, has died at the age of 90, her colleagues announced today (June 20).

Kwolek died Wednesday (June 18) in Wilmington, Delaware, following a weeklong illness, reported the Associated Press.

The pioneering scientist made her fateful discovery in the mid-1960s, as a scientist for the American chemical company DuPont, according to the AP. She invented a liquid crystal solution that, when spun at blistering temperatures of more than 392 degrees Fahrenheit (200 degrees Celsius), could produce lightweight fibers that are stronger than steel.

Kevlar is now widely used in protective armor for soldiers and police officers. The material is also used in some tires, sports equipment and electronics.

Kwolek retired from DuPont in 1989, and was inducted into the National Inventors Hall of Fame in 1994.

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