4,4'-Thiodiphenol cyanate from China
Also known as 4,4'-thiodiphenol cyanate, this compound features a thioether linkage between two phenolic rings with cyanate groups, used in polymer synthesis and flame retardants. Named specifically in HTS 2930.90.26.00 as aromatic organo-sulfur compound per chapter 29 organo-sulfur definitions. The S-C aromatic bonds define its classification.
Duty Rate — China → United States
35%
Rate breakdown
9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
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)
Import Tips
• Cyanate hazard declarations mandatory (UN2922); include flash point data
• Verify no isocyanate impurities that could shift to 2929
• Polymer manufacturers need specific CoA for molecular weight confirmation