Antioxidant 552 (3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide)
Antioxidant 552 is the commercial grade of 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, a non-halogenated organo-phosphorus stabilizer used in polymers. Even as a commercial product, it is the same chemically defined compound and is classified under tariff item 2931.48.00.
Import Duty Rates by Country of Origin
| Origin Country | MFN Tariff | Surtaxes | Total Effective Rate |
|---|---|---|---|
| 🇨🇳China | Free | — | Free |
| 🇲🇽Mexico | Free | — | Free |
| 🇺🇸United States | Free | — | Free |
| 🇩🇪Germany | Free | — | Free |
| 🇯🇵Japan | Free | — | Free |
More Specific Codes
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Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If the product contains halogenated derivatives
Halogenated organo-phosphorus derivatives are classified separately.
If the product is not the specific compound
Other organo-inorganic compounds fall under this residual item.
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• anti-caking agents) do not render the product suitable for a specific use, which could affect classification
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Related Products under Tariff item 2931.48.00
3,9-Dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide
This is the pure chemical compound 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, a non-halogenated organo-phosphorus derivative. It is a separate chemically defined organic compound with phosphorus atoms directly linked to carbon, falling under heading 29.31 and specifically under tariff item 2931.48.00.
CAS 65481-32-7 3,9-Dimethylspiro[5.5]undecane Phosphonate Dioxide
This is the pure compound identified by CAS 65481-32-7, which is 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide. It is a non-halogenated organo-phosphorus compound used as a building block for ligands, and it falls under tariff item 2931.48.00.
DOPO Derivative 3,9-Dimethylspiro Phosphonate
This DOPO derivative is precisely 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, a non-halogenated organo-phosphorus compound used in flame-retardant synthesis. It is classified under tariff item 2931.48.00 as the specific named compound.
Spiro Phosphonate Monomer for Polymer Synthesis
This research-grade spiro phosphonate monomer is chemically 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, used in copolymer production. It is a non-halogenated organo-phosphorus compound and is classified under tariff item 2931.48.00.