Stephanie Louise Kwolek (1923-2014) was an American chemist known for inventing Kevlar. Kwolek was born July 31, 1923 in New Kensington, Pennsylvania. She earned a bachelor’s degree in Chemistry from Margaret Morrison Carnegie College of the Carnegie Institute of Technology (now Carnegie-Mellon University). In 1946, after graduating from what is now Carnegie-Mellon University with a B.S. in Chemistry, Kwolek began her career as a research chemist at DuPont's textile fabrics laboratory in Buffalo, New York. Six years later, she was transferred to the newly built Textile Fibers Pioneering Research Laboratory at DuPont’s Experimental Station in Wilmington, Delaware. It was in Wilmington where Kwolek began researching low temperature processes for the preparation of condensation polymers. Many of these processes were eventually found in products such as Lycra, Nomex, and Kevlar.

In 1964, Kwolek was charged with searching for a new high performance fiber which unexpectedly resulted in the discovery of liquid crystalline solutions of synthetic extended-chain aromatic polyamides and their strong and stiff fibers. It was that technology which was the base of Kevlar fiber. Kwolek then began to work with other scientists to turn the fiber into a commercial product. Kevlar, which is primarily used as a composite, is five times stronger than steel on a weight basis. Kwolek was promoted to Senior Research Chemist in 1967 and a Research Associate in 1974.

By the time of her retirement from DuPont in 1986, Kwolek held sixteen patents, published thirty articles, and has been the recipient of numerous awards such as the American Chemical Society Awards for Creative Innovation (1995), DuPont Lavoisier Medal for Technical Achievement (1995), the National Medal of Technology (1996), the Perkin Medal (1997) as well as the Lemelson-MIT Lifetime Achievement Award (1999). Kwolek also held honorary doctorates from Worcester Polytechnic Institute, Clarkson University, Carnegie-Mellon University, and the University of Delaware.

Kwolek died on June 18, 2014 at the age of ninety. After a forty-year career at DuPont and because of her contributions to the safety of countless policemen across the country with the development of Kevlar, Kwolek received a posthumous honor form the City of Chicago for her contributions to safety. Today, Kevlar has over two hundred uses in ballistics, aircraft, ropes, cables, aerospace, and boating, and industrial fabrics.