Nomex is a flame-resistant and heat-resistant synthetic aromatic polyamide fiber developed by DuPont in the 1960s. It is produced through a condensation reaction between m-phenylenediamine and isophthaloyl chloride monomers. The resulting long-chain polymer is spun into fibers that are less rigid than other aramids due to bends in the polymer chain. Nomex fibers are widely used for heat insulation, electrical insulation, and protective clothing such as in aviation, firefighting, and auto racing due to their flame-resistant and heat-resistant properties.