Obituary: Kevlar inventor Stephanie Kwolek

By Bill Bregar
Senior Staff Reporter

Published: June 20, 2014 11:55 am ET
Updated: June 20, 2014 2:25 pm ET

Image By: DuPont Co. Stephanie Kwolek and her invention, Kevlar, have been credited with saving countless lives.

Related to this story

Topics Materials, Materials Suppliers, Obituaries
Companies & Associations DuPont Co.

Stephanie Kwolek, the inventor of Kevlar — the aramid-fiber body armor that has saved countless lives of soldiers, police and other safety personnel — died June 18, following a brief illness. She was 90.

A low-key industrial chemist at DuPont Co. who achieved international fame, Kwolek discovered Kevlar in the mid-1960s. DuPont commercialized it in 1971. Kevlar most famously goes into bulletproof vests, but it also is used to make super-strong rope, protective gloves for meatpackers, fiber-optic cables and as a reinforcement for composites used in a host of products.

Kwolek was inducted into the Plastics Hall of Fame in 1997 — she is still the only woman in the hall today. That same year, she received the prestigious Perkin Medal from the Society of Chemical Industry’s American Section. Kwolek entered the National Inventors Hall of Fame in 1995. She also is a member of the Engineering and Science Hall of Fame. In 1996, she received the National Medal of Technology in a White House ceremony. 

Kevlar aramid fibers are, by weight, five times stronger than steel.

The International Association of Chiefs of Police reports that more than 3,100 law enforcement officers have been inducted into the IADP/DuPont Kevlar Survivors’ Club. The organization documents when a bulletproof vest saves a life. Many of these survivors met Kwolek and poured out their emotions and thanks. She signed many of their Kevlar vests.

She also starred in DuPont advertisements.

But Kwolek did her work quietly, in the laboratory. She had joined DuPont in 1946. DuPont already was a well-known fiber innovator thanks to nylon, Dacron polyester and Lycra spandex when Kwolek began her work leading to Kevlar. At first, the researchers wanted to develop a lightweight fiber for tires that would boost gas mileage in cars, she recalled in a Plastics News profile when she entered the Plastics Hall of Fame.

Kwolek was trying to find a good solution for spinning the fibers. She hit on dissolving PBA in amide/salt solvents. She described the details of invention in a 1993 speech: “The solution was unusually (low viscosity), turbid, stir-opalescent and buttermilk in appearance. Conventional polymer solutions are usually clear or translucent and have the viscosity of molasses, more or less. The solution that I prepared looked like a dispersion but was totally filterable through a fine pore filter. This was a liquid crystalline solution, but I did now know it at the time.”

The researchers were surprised when the fibers appeared to be super-strong. “Lest a mistake had been made, I did not report these unexpected results until I had the fibers retested several times,” she said.

Kwolek learned that the fibers could be made even stronger by heat-treating them. The polymer molecules, shaped like rods or matchsticks, are highly oriented, which gives Kevlar its extraordinary strength.

Kwolek gave frequent talks to students, encouraging them to get into science. Tire-makers eventually adopted cheaper steel-belted radials, deciding against Kwolek’s invention.

Kevlar went onto greater fame: Stopping bullets and saving lives.

Kwolek was “exceptional”, said Jay Gardiner, president of the Plastics Academy, which administers the Plastics Hall of Fame. Kevlar is an example of a super-tough material that shows the public that plastics are far more than “cheap” and disposable, he said.

DuPont Chairman and CEO Ellen Kullman said in a statement: “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. … She leaves a wonderful legacy of thousands of lives saved and countless injuries prevented by products made possible by her discovery.”

Kwolek spoke about her life and work in this 2013 video from the Museum of Science in Boston.


Comments

Obituary: Kevlar inventor Stephanie Kwolek

By Bill Bregar
Senior Staff Reporter

Published: June 20, 2014 11:55 am ET
Updated: June 20, 2014 2:25 pm ET

Post Your Comments


Back to story


More stories

Image

Total to buy majority stake in Polyblend

November 20, 2014 10:04 am ET

French oil and gas giant Total SA will buy a 68 percent stake in Germany's Polyblend GmbH, a subsidiary of Polymer-Chemie GmbH.    More

Image

Silica can replace plastic microbeads

November 19, 2014 6:00 am ET

As cosmetics and soap makers face pressure to remove plastic microbeads from their products, Evonik Industries touts its new silica-based microbeads...    More

Chase Plastics building new Indiana distribution center

November 18, 2014 11:13 am ET

Resin distributor Chase Plastics will invest $5.4 million to build a new distribution center in South Bend, Ind.    More

Image

Dow Corning opens European health care center

November 18, 2014 6:00 am ET

Dow Corning Corp. has opened an expanded health care application center at its European headquarters in Seneffe, Belgium.    More

Image

Bayer flame-retardant PC blends keep evolving

November 18, 2014 6:00 am ET

Bayer MaterialScience (BMS) introduced a further development on the back of the 3000 flame-retardant polycarbonate blends it introduced in 2005.    More

Market Reports

Plastics in Brazil - State of the Industry Report

This in-depth report examines the Brazilian plastics industry from a historical and geographical context. Our analysts provide insight on economic trends and forecasts, growing manufacturing sectors that utilize plastics, private investment opportunities, market environment challenges, and innovations in R&D.

Data tables and charts on producer prices, trade, plastics production and end market indicators is also included.

Learn more

Plastics Recycling Trends in North America

This report is a review and analysis of the North American Plastics Recycling Industry, including key trends and statistics based on 2013 performance. We examine market environment factors, regulatory issues, industry challenges, key drivers and emerging trends in post-consumer and post-industrial recycling.

Learn more

Injection Molders Market Report & Ranking 2014

This special package contains our 132-page 2014 Market Report on the Injection Molding segment and our exclusive 2014 RANKINGS database of 500+ Injection Molders for a discounted package price.

Learn more

Upcoming Plastics News Events

January 14, 2015 - January 14, 2015Plastics in Automotive

February 4, 2015 - February 6, 2015Plastics News Executive Forum 2015

June 2, 2015 - June 3, 2015Plastics Financial Summit - Chicago 2015

September 16, 2015 - September 18, 2015Plastics Caps & Closures - September 2015

October 27, 2015 - October 29, 2015Plastics Financial Summit - New York - 2015

More Events