Stephanie Kwolek

Kwolek grew up in New Kensington, Pennsylvania, the daughter of Polish immigrants; her father, an amateur naturalist, died when she was ten, and her seamstress mother, a perfectionist about her own work, gently steered her daughter away from a career in fashion design toward something more exacting. Kwolek wanted to become a physician and studied chemistry at Carnegie Mellon's Margaret Morrison College as a way to fund medical school, graduating in 1946. She took a chemist's job at DuPont's Buffalo laboratory that same year purely to save tuition money, and a fast job offer from her mentor there, William Hale Charch, meant she never left the company, or the field, for the next four decades.

Kwolek spent the 1960s searching for a lighter fiber to reinforce car tires, working with a class of stiff, rod-like polymers under research fellow Paul Morgan. In one batch the resulting solution came out cloudy and thin, closer to buttermilk than the thick, clear syrup chemists expected, and most researchers would have thrown it out. Kwolek had it spun anyway, over a technician's doubts, and the resulting fiber tested five times stronger than steel by weight while weighing almost nothing. DuPont released it commercially in 1971 as Kevlar and patented it in 1974. She also helped develop Nomex, the flame-resistant fiber DuPont introduced in 1961, and held twenty-eight patents by the time she retired in 1986.

Kevlar has been credited with saving thousands of police officers and soldiers wearing body armor made from it, and it generated billions of dollars for DuPont, but Kwolek signed the patent over to the company and never received a share of that money herself. She spent her retirement doing the opposite of resting on the discovery: touring classrooms nationwide performing the "nylon rope trick" for schoolchildren, mentoring young chemists, and serving on National Academy of Sciences panels, almost all of it unpaid. For most of her forty-year career she worked as one of very few women in DuPont's research labs, largely uncredited outside the company until recognition caught up with her late in life.

Kwolek died in Talleyville, Delaware, on June 18, 2014, at ninety; the same week, DuPont sold its one millionth Kevlar bullet-resistant vest. She had already been inducted into the National Inventors Hall of Fame in 1995, the fourth woman to receive that honor, and had received the National Medal of Technology and Innovation in 1996. Kevlar now appears in more than two hundred products, from tires to undersea cables to smartphone cases, and the Royal Society of Chemistry named a biennial award in materials chemistry after her. The rope trick she performed for children is still taught by chemistry educators as a way to make polymer science visible.

Stephanie Kwolek's life against the full span of the corpus.

• "Nylon Rope Trick" (ACS award paper) article
  A classroom demonstration of nylon synthesis she helped popularize 1959
• Nomex invention
  Flame-resistant aramid fiber, developed with DuPont colleagues 1961
• Kevlar invention
  Discovered in 1965, released commercially in 1971 1965
• U.S. Patent 3,819,587 patent
  The Kevlar patent, assigned to DuPont 1974

• 1933 aged ~10 Her father dies when she is ten
• 1946 aged ~23 Graduates Carnegie Mellon and is hired by DuPont in Buffalo
• 1950 aged ~27 Her research group relocates to Wilmington, Delaware
• 1965 aged ~42 Discovers the liquid-crystal polymer solution that becomes Kevlar
• 1971 aged ~48 DuPont releases Kevlar commercially
• 1974 aged ~51 Granted the Kevlar patent
• 1986 aged ~63 Retires from DuPont as a research associate
• 1995 aged ~72 Inducted into the National Inventors Hall of Fame The fourth woman ever inducted.
• June 18, 2014 aged 90 Dies in Talleyville, Delaware, at ninety

• Wallace Carothers 1896–1937
  Led the DuPont research that produced neoprene and nylon and established polymer science. carried forward the DuPont polymer program of
• Grace Hopper 1906–1992
  Computer scientist and Navy rear admiral who helped develop early programming languages and computing. broke similar ground for women in science
• Katherine Johnson 1918–2020
  NASA mathematician whose orbital trajectory calculations supported the Mercury and Apollo crewed flights. broke similar ground for women in science
• Rachel Carson 1907–1964
  Marine biologist whose book Silent Spring launched the modern environmental movement. published a landmark work of American science alongside