Wilmington, Del. • Stephanie Kwolek, a pioneering female chemist at DuPont who invented the exceedingly tough fibers widely used in Kevlar body armor, has died, colleagues said Friday. She was 90.
Kwolek died Wednesday at a hospital in Wilmington where she had lived, said her friend Rita Vasta, a chemist who also worked at DuPont. Vasta said Kwolek had been ill about a week though she didn't know the cause of death.
Kwolek made her discovery in the mid-1960s while working on specialty textile fibers, according to DuPont's website. She invented a liquid crystalline solution that could be spun into the exceptionally strong fibers now used worldwide in police and military protective equipment.