Nearly resigned to the trash bin, super strong Kevlar now saves lives

Stephanie Kwolek

They call Superman the “Man of Steel” because steel ranks among the strongest known materials. But modern synthetic materials, like Kevlar, are far stronger and lighter.

Kevlar is used to make bulletproof vests and other lifesaving protective equipment. However, it was discovered by accident and nearly ended up thrown in the trash.

In the mid-1960s, a chemist at DuPont, Stephanie Kwolek, was looking for a way to make lighter, stronger tires to improve fuel efficiency. Policy experts then feared global gas and oil shortages. In the lab, Kwolek noticed a batch of synthetic polymers that had formed into a cloudy, runny consistency rather than the usual and expected clear syrupy consistency.

Colleagues advised her to chuck it in the trash. However, Kwolek decided to investigate and discovered that the material could be spun into fibers of extraordinary strength and stiffness, especially given their light weight. Thus, Kevlar was born. Five times stronger than steel (based on equal weight) but lighter than fiberglass, Kevlar is a choice material when strength and light weights are needed.

These days, Kevlar is most famous for its use in bulletproof vests. Over a million Kevlar vests have been sold, and more than 3,000 police officers so far have been saved by the vests. Soldiers rely on Kevlar vests, but you’ll also find them in kayaks and spacecraft.