What material did DuPont scientists originally call Polymer 6.6 when it was first produced in 1935? Nylon. The name referred to nylon 6,6, a synthetic polyamide made from two six-carbon building blocks.
The material was developed by a DuPont research team led by American chemist Wallace Carothers. On February 28, 1935, researchers produced a promising nylon 6,6 polymer at DuPont’s Experimental Station in Delaware. Its strength, elasticity, high melting point, and resistance to water made it especially useful as a fiber.
The “6,6” identifies the six carbon atoms in each of the two starting monomers: hexamethylenediamine and adipic acid. It is not a grade number or a date. DuPont later patented the material in 1938 and introduced nylon commercially in 1939, first promoting it for toothbrush bristles before nylon stockings made it famous.
Nylon is a family of polymers, so nylon 6,6 is only one type. Nylon 6, made from a different starting material, is another major form.