In the Middle Ages, knights used armor to protect their bodies against the sword slashes of their opponents. Today that armor would be no match for a rifle or pistol bullet. However, new technology that came out of basic research in plastics has developed a material that can withstandmost bullets.
News You Can Use
- Kevlar is a long-chain polymer with structural similarities to nylon. It was developed at DuPont by Stephanie Kwolek. Originally interested in medical school, she soon became very enthusiastic about her work on new polymers. She noted one mixture was cloudy instead of clear and sensed that it might form a strong polymer. Her hunch was correct and Kevlar was born.
- The material needs to be kept inside of some sort of protective fabric. The polymer itself cannot be exposed to direct sunlight because it will become less dense and will lose some of its capabilities. Similar problems are seen if the material gets wet.
- Kevlar is an extremely strong material. It is widely used for the interior of bicycle tires. Protective gloves and boots will often contain Kevlar as one component of the material. Some cellular phones have an interior pad of Kevlar that protects the components if the phone is dropped. Kevlar is used in some boat hulls because it is lightweight and can withstand impact better than fiberglass or other materials.
- Watch a video demonstrating the protective capabilities of Kevlar armor: https://www.youtube.com/watch?v=CDfehw6LIR0
Show What You Know
Use the links below to learn more about Kevlar. Then answer the following questions.
- What were two qualities of the new material that Stephanie Kwolek discovered?
- What type of compound is Kevlar?
- What are some problems in working with Kevlar?
- Work through the interactive lesson about Kevlar on the following web page: http://www.lbl.gov/MicroWorlds/Kevlar/KevlarPutting.html
- What is one rather unique application for Kevlar?