Stephanie Kwolek was an American chemist who is best known for inventing the first of a family of synthetic fibers of exceptional strength and stiffness: poly-paraphenylene terephthalamide—better known as Kevlar.
Kwolek was born in 1923 in New Kensington, Pennsylvania. Her father, John Kwolek, was a naturalist and Kwolek spent hours exploring the woods and fields near her home and filling scrapbooks with leaves, wildflowers, seeds, grasses annotated with descriptions. He died when Kwolek was 10, and her mother, Nellie was forced to take over financial responsibility for the family. Kwolek inherited a love of fabrics and sewing from her mother, and briefly entertained the idea of becoming a fashion designer.
In 1946, Kwolek gained a Bachelor of Science degree with a major in chemistry from Margaret Morrison Carnegie College of Carnegie Mellon University. She had planned to become a doctor, and took a position at DuPont’s Buffalo, New York, facility to save up enough money to attend medical school. Kwolek was interviewed for the position by
W. Hale Charch, and her assertiveness in asking him to make a decision on whether or not she would be offered the position led to him dictating an offer letter while she waited. In addition to her assertiveness, there were a shortage of male applicants for the post due to World War II which is said to have influenced the fact that Kwolek was hired for a job in a male dominated area of research. She was One of the first women research chemists. Kwolek’s work on polymer research proved so interesting that she abandoned her plans for medical school and instead focused her attention on chemistry. In 1950, she moved to Wilmington, Delaware to continue working for DuPont. In 1959 Kwolek won what would become the first of many awards, a publication award from the American Chemical Society(ACS) for her paper, The Nylon Rope Trick. The paper demonstrated a way of producing nylon in a beaker at room temperature. It is still the basis of a common classroom experiment.
In 1964, Kwolek and a team of chemists called the Pioneering Research Laboratory were exploring new polymer fibers and ways to make them in order to create a high-performance fiber. It was predicted that there would be a gasoline shortage, and Kwolek and her team were convinced that strong, lightweight fibers could be used to reinforce car tyres – lighter, stiffer tyres would lead to less gasoline usage. Kwolek discovered that under certain conditions, molecules of the polymers poly-p-phenylene terephthalate and polybenzamide line up in parallel and form liquid crystalline solutions. These solutions could then be spun directly into oriented fibers of very high strength and stiffness. After this breakthrough, many fibres were spun from liquid crystalline solutions and this led to a new field of polymer chemistry. In 1971, Kwolek’s discovery that fibres could be made far stronger by treat treating them led to the invention of Kevlar, a synthetic material that is five times as strong as steel. She signed over the Kevlar patent to DuPoint and was not a part of the team that went on to develop practical uses for Kevlar. It is now used in more than 200 applications, including bullet-proof vets, tennis rackets, cut-resistant gloves, armoured cars and hurricane safe rooms and as part of mobile phones. In 1980, Kwolek received the Chemical Pioneer Award from the American Institute of Chemists, and an Award for Creative Invention from the American Chemical Society.
In 1986, Kwolek retired from her position as a research associate at DuPont but she continued to consult for them, and served on both the National Research Council and the National Academy of Sciences. Kwolek also turned her attention to recruiting young children, especially girls into scientific fields and tutored students in chemistry. Kwolek invited and wrote numerous classroom demonstrations that are still used in schools, including the Nylon Rope Trick.
Kwolek’s research has resulted in her being the recipient or co-recipient of 17 U.S. patents. In 1995, Kwolek became the fourth woman to be inducted into the National Inventors Hall of Fame. That same year, she was awarded the DuPont company’s Lavoisier Medal for outstanding technical achievement for her discovery of Kevlar. At the time of her death in 2014, she was the only female employee to receive that honour. In 1996, Kwolek received the National Medal of Technology and the IRI Achievement Award, a year later she was awarded the Perkin Medal from the American Chemical Society. In 2003 she was inducted into the National Women’s Hall of Fame. Kwolek has been awarded honorary degrees from Carnegie Mellon University (2001), Worcester Polytechnic Institute (1981) and Clarkson University (1997). The Royal Society of Chemistry grants a biennial ‘Stephanie L Kwolek Award’, “to recognise exceptional contributions to the area of materials chemistry from a scientist working outside the UK”. In addition to these accolades, police officers and others who depend on the Kevlar in their bulletproof vests would often come up to Kwolek and tell her of their experiences, with one police officer even having her autograph his bulletproof vest. Kwolek was pleased with her discovery, as “So many people work all their lives and they don’t make a discovery that’s of benefit to other people”, whereas she did exactly that with the invention of Kevlar.