Stephanie L. Kwolek, Inventor of Kevlar, Is Dead at 90 kevlar-er Stephanie L. Kwolek, Inventor of Kevlar, Is Dead at 90 Stephanie L. Kwolek, Inventor of Kevlar, Is Dead at 90 kevlar-er Stephanie L. Kwolek, Inventor of Kevlar, Is Dead at 90. Stephanie L. Kwolek, Inventor of Kevlar, Is Dead at 90