3,3'-Diaminobenzidine (Tetraaminobiphenyl) from China
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 — China → United States
37.5%
Rate breakdown
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China
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