The fibers form a protective barrier against gunfire. Bullets lose their shape when they strike Kevlar. Those bullets look like mushrooms, and do not enter the body. Most threats to police and security officers come from handguns. They wear Kevlar vests to protect the upper body. Soldiers wear more extensive clothing protected with Kevlar against heavier ammunition.
Kevlar might not have been invented had Stephanie Kwolek been able to seek a career in medicine. From childhood, she wanted to be a doctor. But she lacked the money for a medical education.
Today, thousands of people are glad that Stephanie Kwolek became a research chemist. In that job, she developed the first liquid crystal polymer. The polymer was a chemical product that formed the basis for Kevlar.
Stephanie Kwolek was born in 1923 in New Kensington, Pennsylvania. As a child, Stephanie loved science. Later, she studied chemistry and other sciences at a Pennsylvania college now known as Carnegie Mellon University.
She got a job with the DuPont chemical company in 1946. It was the beginning of a career with the company that lasted about 40 years.
By the 1960s, Dupont already had produced materials like nylon and Dacron. The company wanted to develop a new fiber. Stephanie Kwolek was part of a DuPont research group that asked to work on its development.
At the time, she was searching for a way to make a material strong enough to use on automobile tires. If tires could be improved, automobiles would need less fuel. Ms. Kwolek needed a new way to make stiff, resistant fibers for the job.
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2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25
2013-11-25