Stephanie Kwolek Dies At 90

Stephanie L. Kwolek, the DuPont chemist whose synthesis of the first liquid-crystal polymer led to the development of Kevlar, the light, superstrong aramid fiber used in bulletproof vests, body armor, tires, and countless types of sports equipment, died in Wilmington, Del., on June 18. She was 90 years old.

“We are all saddened at the passing of DuPont scientist Stephanie Kwolek, a creative and determined chemist and a true pioneer for women in science,” DuPont Chief Executive Officer Ellen J. Kullman said in a statement. “She leaves a wonderful legacy of thousands of lives saved and countless injuries prevented by products made possible by her discovery.”

Early in her career, Kwolek joined the search for polymers and lower-temperature condensation processes needed to produce specialty fibers, including those that could be used in lighter, more fuel-efficient tires. Researchers struggled to develop a stiffer and tougher nylon-related fiber until 1965, when Kwolek experimented with polyamide molecules and synthesized a liquid-crystal solution that could be cold-spun into fibers of unprecedented strength and stiffness. That research led to the introduction of Kevlar in the early 1970s.

Born to Polish immigrant parents in New Kensington, Pa., Kwolek became enthralled with science while exploring nature with her naturalist father, who died when she was just 10 years old. She earned a bachelor’s degree in chemistry from Margaret Morrison Carnegie College (now Carnegie Mellon University) in Pittsburgh in 1946. She then joined DuPont as a laboratory chemist in Buffalo, intending to stay with the company just long enough to save up for medical school. However, she found her work to be so exciting that she decided to remain with the company, eventually moving to DuPont’s Pioneering Lab in Wilmington. She retired in 1986.

Kwolek received the Perkin Medal in 1997 and the National Medal of Technology in 1996. She was inducted into the National Inventors Hall of Fame in 1995. She was an emerita member of ACS, joining in 1947.

Kwolek leaves no survivors.