Cyclized Rubber (Alkylated Chlorosulfonated Rubber)
Cyclized rubber is produced by treating natural rubber with acids to create cyclic structures, resulting in a harder derivative used in paints and varnishes. It is supplied in primary flake or powder form. As a chemically modified natural polymer, it falls under this tariff item for natural polymers not elsewhere specified.
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
This product may fall under a more specific subheading:
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right tariff item — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Confirm the cyclized rubber is chemically modified natural rubber, not a synthetic polymer, to justify classification under this item
• Provide technical data sheets showing the modification process
• Check if the product is excluded by Chapter 40 notes on synthetic rubber
Related Products under Tariff item 3913.90.00
Alginic Acid Powder
Alginic acid powder is a natural polymer extracted from brown seaweed, used in food gelling and pharmaceutical encapsulation. It is supplied in primary powder form. As a natural polymer not elsewhere specified, it falls under tariff item 3913.90.00.
Carboxymethyl Guar Gum
Carboxymethyl guar gum is a chemically modified derivative of guar gum, a natural polysaccharide, with carboxymethyl groups added to enhance water solubility for cosmetics and oil recovery applications. It is supplied in primary powder form. As a modified natural polymer, it is classified under tariff item 3913.90.00.
Carboxymethyl Starch Powder
Carboxymethyl starch powder is a starch derivative modified with carboxymethyl groups, used as a binder in paper and pharmaceutical tablets. It is supplied in primary powder form. As a chemically modified natural polymer, it falls under tariff item 3913.90.00.
Casein Modified Powder
Casein modified powder is chemically hardened casein protein derived from milk, used in industrial coatings and adhesives. It is supplied in primary powder form. As a hardened protein, a modified natural polymer, it is classified under tariff item 3913.90.00.
Cassia Gum Powder
Cassia gum powder derived from cassia tora seeds, a polysaccharide thickener for pet food and industrial applications, in primary powder form. This natural galactomannan polysaccharide derivative is classified under tariff item 3913.90.00 as a modified natural polymer in primary form, not elsewhere specified.
Chitosan Flakes
Chitosan flakes are a natural polymer derived from chitin through deacetylation, sourced from crustacean shells. They are used in water treatment and biomedical applications. Supplied in primary flake form, they qualify as a modified natural polymer under tariff item 3913.90.00.