Colleagues say Stephanie Kwolek, the DuPont chemist who invented the body-armor component Kevlar, has died at age 90.
Her friend Rita Vasta said Friday that Kwolek died Wednesday at St. Francis Hospital in Wilmington. Vasta didn't know the cause of death but said Kwolek had been ill for about a week.
Kwolek made her discovery in the mid-1960s while working on fiber for radial tires.
She invented a liquid crystalline solution that could be spun into fibers five times stronger than steel. Kevlar is widely used in protective equipment by police and the military.
Vasta says Kwolek was proud of her invention and worked to get more women into science.
Visitation is planned June 27 at a Wilmington funeral home, followed by a Catholic funeral Mass June 28.
