The inventor of Kevlar was the chemist Stephanie Kwolek, working for duPont Chemical in 1966.
Kevlar is five times stronger than the same weight of steel. It is a polymer--an important class of compounds starting with the polyester in your socks and ending with the materials that repair arteries.
Kevlar does not rust or corrode. It is used as bullet-resistant shielding, from vests to windows. There might also be Kevlar in your brake cables, your skis, and in the materials for your building.
Ms. Kwolek invented many other polymers we use today. She was born in 1923, and worked for 40 years at DuPont. Twenty-eight patents are held by her in that 40 years. She was inducted into the Inventor's Hall of Fame in 1995 (heck, what took them so long?) I learned about her right after I learned about pop-up books, right there at the Smithsonian.
She was originally planning to be a doctor. She's saved a lot of lives out there without medical school. Nowadays she's semi-retired, serving on a lot of Science Foundation boards.
Some people just never give up.
Wikipedia has an article about her here.