Doverphos S-480 Phosphite Ester Antioxidant
Doverphos S-480 is the trade name for 4,4'-diphenylbisphosphonous acid di(2',2",4',4"-di-tert-butyl)phenyl ester, a high-performance secondary antioxidant for polyolefin processing. Classified specifically under HTS 2931.90.10.00 as the named aromatic organo-inorganic phosphorus compound per Chapter 29 hierarchy.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If organo-sulfur content dominates over phosphorus linkage
Chapter notes separate organo-sulfur (2930) from other organo-inorganic (2931); sulfur-carbon priority determines heading.
If for retail-packed or diluted preparations
Consumer chemical preparations fall outside Chapter 29 per exclusion notes into prepared binders Chapter 38.
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Import Tips & Compliance
• Include TSCA certification for US import; REACH compliance docs for EU origin goods
• Avoid bulk mixtures - pure compound qualifies for 2931; admixtures go to 3824
Related Products under HTS 2931.90.10.00
4,4'-Diphenylbisphosphonous Acid Di(2',2",4',4"-di-tert-butyl)phenyl Ester
This is a specific aromatic organo-inorganic compound containing phosphorus directly linked to carbon atoms, classified under HTS 2931.90.10.00 as a named product in the 'Other' category of organo-inorganic compounds. It is used primarily as a stabilizer and antioxidant in polymer processing and high-performance plastics.
Irgafos 126 Stabilizer (4,4'-Diphenylbisphosphonous Acid Derivative)
Commercial-grade Irgafos 126, chemically 4,4'-diphenylbisphosphonous acid di(2',2",4',4"-di-tert-butyl)phenyl ester, used as a phosphite antioxidant in polypropylene and polyethylene resins. Falls under HTS 2931.90.10.00 as the specifically named aromatic organo-inorganic compound with phosphorus-carbon bonds.
Phosphonous Acid Bis(2,4-di-tert-butylphenyl) Ester Derivative
Technical-grade phosphonous acid derivative matching 4,4'-diphenylbisphosphonous acid di(2',2",4',4"-di-tert-butyl)phenyl ester specification, used in nylon and engineering plastics stabilization. HTS 2931.90.10.00 covers this exact aromatic organo-inorganic structure with direct P-C bonds.