Perfluorobutyl Sulfonamide (FC 401)

Perfluorobutyl Sulfonamide, identified by its CAS registry number 1896-62-4 and often designated as FC 401, represents a critical specialized fluorochemical intermediate within the perfluorinated compound family. Structurally characterized by a four-carbon perfluorinated chain attached to a sulfonamide functional group, this white crystalline solid serves as a foundational building block for synthesizing high-performance fluorinated surfactants, specialty polymers, and repellent finishes. Its unique chemical architecture provides exceptional thermal stability and chemical resistance, derived from the high strength of the carbon-fluorine bonds within the nonafluorobutyl tail. As environmental regulations evolve, FC 401 has emerged as a shorter-chain alternative to perfluorooctane-based materials, maintaining effective surface-active properties while offering a different toxicological profile. It is primarily utilized in industrial settings where low surface tension and high wetting efficiency are required under extreme conditions. Professionals value this reagent for its precise reactivity in nucleophilic substitutions and its consistent purity during large-scale chemical manufacturing processes utilized globally.