Most people are familiar with Kevlar, a material with a high tensile strength-to-weight ratio that makes it five times stronger than steel. What you may not know is that Kevlar is the registered trademark for a para-aramid synthetic fiber developed by organic chemist Stephanie Kwolek.
With dreams of practicing medicine, Kwolek earned her bachelor’s degree in chemistry. Looking for work before heading to medical school she applied at various labs including the DuPont Company. When interviewed at DuPont she was told a decision about the position would be made in the next two weeks, Kwolek looked at the interviewer and asked if she could know more quickly as she had other offers on the table. The story goes that she was offered the job on the spot partially due to her assertiveness. She started working at what she thought would be a temporary job in 1946. But once she discovered how much she loved the work, it turned into a forty-year career in organic chemistry research.
In 1964, seeing the gas crisis looming, Kwolek’s research group began searching for a strong lightweight fiber to be used in tires. During experimentation she created a liquid crystal solution that was different than most polymer solutions. This cloudy solution was usually thrown away, but she persuaded a technician to try and spin it into fibers.
What she found was this new fiber wouldn’t break and was incredibly strong. This fiber was the back bone of Kevlar which was introduced to the public in the early 1970s and can now be found in hundreds of applications.
Kwolek won the first of numerous awards in 1959 after publishing a paper with a colleague that explained a way to demonstrate the production of nylon in a beaker at room temperature. The Nylon Rope Trick won a publication award and is still the basis for a popular classroom experiment. For her discovery of Kevlar she was awarded DuPont’s Lavoisier Medal, the Perkin Medal, and was inducted into the National Inventors Hall of Fame. In 2008 the Royal Society of Chemistry created the Stephanie L. Kwolek Award given biennially.
Written by Angela Goad