Spotlight on Stephanie Kwolek (1923-2014), Chemist and Inventor Extraordinaire

Oct 18, 2023

Stephanie Kwolek: 100 Women of the Year. TIME


One of the most important chemists that you’ve probably never heard of is Stephanie Louise Kwolek (Polish: Chwalek), who invented polyparaphenylene terephthalamide, a stronger-than-steel and lighter-than-fiberglass polymer, which is popularly known as Kevlar®.

Born to Polish immigrant parents in New Kensington, Pennsylvania, Kwolek developed a love of textiles and fabrics from her mother, a seamstress—in fact, at one point the 4’11” Kwolek considered a career in fashion.

However, fate had other plans, and after graduation from Margaret Morrison Carnegie College in 1946 with a degree in chemistry, Kwolek signed on as a chemist with the DuPont Company. There, she was assigned to work on the development of lightweight, heat-resistant fibers.

One day, unexpectedly, in 1965, she came across a thin, milky solution of polymers that was different from any other polymer solutions she had thus far encountered.

Instead of discarding it as other chemists would probably have done, Kwolek recalled that, “Ordinarily a polymer solution sort of reminds you of molasses, although it may not be as thick. And it’s generally transparent. This polymer solution poured almost like water, and it was cloudy. I thought, ‘There’s something different about this. This may be very useful.’”[1] 

Pound for pound, Kevlar® is five times stronger than steel as well as chemical and flame resistant. Also, it is cheap to manufacture. Besides bulletproof vests, which it is perhaps best known for, Kevlar® has many other applications ranging from fiber-optic cables, helmets, aerospace products, cut-resistant gloves, and car brakes to name but a few.

In honor of the strength and durability not only of Kevlar® but also its inventor whose resiliency in an industry where women chemists were few and far between is legendary, EpicentRx has named its randomized Phase 2b clinical trial in head and neck cancer, KEVLARx. Its lead molecule, nibrozetone (RRx-001) is given with chemotherapy and radiation in KEVLARx to hopefully protect patients from the painfully debilitating complication of oral mucositis that almost 100% of patients experience.