Liquid Polyisoprene Rubber (LIR)
Liquid polyisoprene rubber (LIR) is a low molecular weight liquid derivative of natural cis-1,4-polyisoprene, used as a reactive plasticizer in tires and sealants. It is supplied in primary liquid form in drums. As a modified natural polymer, it is classified under this tariff item.
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
• Document that the LIR is derived from natural rubber, not synthetic polyisoprene, to support classification
• Ensure the liquid form qualifies as primary forms under Chapter 39
• Verify the product is not excluded as a lubricating preparation under heading 27.10 or 34.03
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.