KWOLEK UNIQUE MIXTURE OF CHEMISTRY, FAME: TIRE RESEARCH FIELDS LIFE-SAVING KEVLAR FIBERS

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This Thursday, Stephanie L. Kwolek will become the first woman inducted into the Plastics Hall of Fame. But she has achieved an even rarer feat for an industrial chemist—celebrity.

Kwolek, whose work led to Kevlar fibers, stars in television and magazine advertisements sponsored by her employer of 40 years, DuPont Co.

Most research chemists toil in obscurity to the outside world, although they certainly may be ``stars'' within their own company.

Kevlar aramid fibers — by weight, five times stronger than steel — go into some high-profile products, especially the bulletproof vests credited with saving the lives of more than 2,000 police officers.

Kwolek, 73, gets to meet many of those men and women, through a group called the Survivors Club. The scene is repeated across the country. A cop, whose vest stopped a gun blast from a drug dealer or bank robber, steps forward to embrace the woman whose curiosity and persistence made that vest possible.

``It's rather emotional, particularly when you meet their parents and the families,'' she said.

DuPont and the International Association of Chiefs of Police sponsor the Survivors Club. The coordinator, Bill Brierley, a retired police chief from Newark, Del., said the group documents cases when a bulletproof vest saved a life. The club holds ceremonies.

``It's usually always a formal type of an event, but there's a lot of human emotion. There's a lot of pride on her part,'' Brierly said.

The stories are gripping. Like the bicycle cop in Norfolk, Va., who interrupted a drug deal. The dealer opened fire with 9mm gun.

``It would have been a fatal round [without the vest.] It just hit him smack in the chest and he went flying over the handlebars,'' Brierley said.

He lived. Later he asked Kwolek to autograph his vest.

As criminals break out heavy artillery, police use of the vests keeps increasing. Some 64 percent of police routinely wear body armor, a dramatic increase from just few years ago.

Apparently the added protection helps. Last year, 117 police officers died in the line of duty — the lowest number of deaths in 38 years.

``We know that body armor's playing a vital role,'' Brierley said.

The DuPont ads capture Kwolek's creativity.

``DuPont wanted to honor some of its employees and so they asked some of their inventors to be in these TV programs,'' she said.

Instead of hiring actors, the advertisements feature the real thing.

Kwolek, who retired from DuPont in 1986 and holds 17 patents, also gives frequent speeches.

``I talk to children in grade school about science and the excitement connected with science. I also talk to college and university students. I've made videotapes [for the Smithsonian Institution] where I talk about my career and work.''

Even given the advertisements, her name still may not be a household word throughout America. But in a society obsessed with Michael Jackson and Dennis Rodman, Kwolek feels she is a good role model — and not just for women.

But she says that business should do more.

``I think industry is going to have to put much more emphasis on acknowledging people who are outstanding in science and who have made contributions to society other than in sports. But it's very difficult to make science understandable in a very few words.

``It isn't like sports where people can watch, and everybody understands the vocabulary to describe what's happening. It isn't that way with science.''

OK, how about words like polybenzamide?

When Kevlar was born, Kwolek was experimenting with ways to synthesize those substances and make a new fiber. It was 1964. Kwolek was working in DuPont's experimental station for fibers in Wilmington, Del.

Thanks to well-known products such as Nylon, Dacron polyester and the elastic material Lycra spandex, DuPont already was known as a fibers powerhouse when Kwolek's work started.

But Kwolek and the other researchers were thinking tires, not bulletproof vests.

``There was talk of a future energy shortage, so we were thinking about finding a very strong and stiff but lightweight fiber that would be used in lightweight tires,'' she said.

Trying to find a suitable spinning solution, Kwolek hit upon dissolving PBA in amide/salt solvents.

In a 1993 speech, she spelled out the details: ``The solution was unusually [low viscosity], turbid, stir-opalescent and buttermilklike 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 not know it at the time.''

Usually, such watery solutions cannot be spun into fibers, but Kwolek convinced the man who ran the spinning unit to try it, and it worked.

But she got another surprise: 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.

She found that the fibers could be made even stronger by heat-treating them briefly.

The polymer molecules, shaped like rods or matchsticks, line themselves up to become highly oriented, giving Kevlar its tremendous strength.

Kevlar, which was introduced commercially in 1971, goes into more than bulletproof vests. Other markets include rope, protective gloves for meatpackers, fiber-optic cables and composites for aerospace, boats and sporting goods.

Some Kevlar is used in tires, the original intended market, but tire makers turned to cheaper steel-belted radials.

Today, according to DuPont, Kevlar consists of long molecular chains produced from polyparaphenylene terephthalamide.

This year has been a busy one for Kwolek.

In March, she received the 1997 Perkin Medal from the Society of Chemical Industry's American Section.

The Perkin Medal is considered industry's highest honor for outstanding work in applied chemistry. On June 19 at NPE 1997, Kwolek will join the Plastics Hall of Fame.

In 1995, she was inducted into the National Inventors Hall of Fame in Akron, Ohio. She also is a member of the Engineering and Science Hall of Fame in Dayton, Ohio.

Last year, she went to the White House to receive a National Medal of Technology.

Kwolek also was the recipient of an American Innovator Award by the U.S. Patent and Trademark Office.