3,3'-Diaminobenzidine (Tetraaminobiphenyl) from Mexico
3,3'-Diaminobenzidine, a tetrafunctional aromatic polyamine also called tetraaminobiphenyl, is named in HTS 2921.59.1700. It is essential for polybenzimidazole polymers and high-performance engineering plastics.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• Include polymerization inhibition certificates if stabilized for transport
• High purity grades (>98%) require HPLC chromatograms for duty verification
• Prevent oxidation during shipping; use nitrogen-purged containers