A lot of folks owe their lives to Stephanie Kwolek:

Police Lt. David Spicer took four .45-caliber slugs to the chest and arms at point-blank range and lived to tell about it. Like thousands of other police officers and soldiers shot in the line of duty, he owes his life to a woman in Delaware by the name of Stephanie Kwolek.

Kwolek, who died Wednesday at 90, was a DuPont Co. chemist who in 1965 invented Kevlar, the lightweight, stronger-than-steel fiber used in bulletproof vests and other body armor around the world.

A pioneer as a woman in a heavily male field, Kwolek made the breakthrough while working on specialty fibers at a DuPont laboratory in Wilmington. At the time, DuPont was looking for strong, lightweight fibers that could replace steel in automobile tires and improve fuel economy.

Details about how she came upon her discovery are at the link.