Perfluorobutyric Acid Methyl Ester from Mexico
Methyl ester of perfluorobutanoic acid, maintaining full perhalogenation on acyclic chain. Classified 2903.78.00.00 as ester remains with parent perhalogenated hydrocarbon per chapter classification rules. Used as fluorinated solvent intermediate.
Duty Rate — Mexico → United States
100%
Rate breakdown
9903.04.6096.3%Pharmaceuticals Annex IV: patented pharma articles — 100% floor rate
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)
Import Tips
• Esters classified with parent acid; reference corresponding acid HTS in documentation
• Lower flammability than typical esters; still requires UN 1760 shipping papers
• Avoid water contamination during storage to prevent hydrolysis back to acid