Polyisobutylene Rubber PIB
Polyisobutylene (PIB) is a synthetic rubber polymer derived from isobutylene monomer, imported in primary pellet form. With isobutylene comprising over 95% by weight, it is classified as 'other' olefin polymers under tariff item 3902.90.00, as it is not specifically named in other subheadings of heading 39.02.
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 |
PGA flags
No agency flag on this HTS number in the CBSA Single Window matching criteria.
CBSA Single Window matching criteria, unknown
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If the PIB is compounded with additives and has rubber-like properties for use as synthetic rubber
Chapter 40 covers synthetic rubber; if the product meets the definition of synthetic rubber, it may be classified there rather than in Chapter 39.
If the polymer is predominantly polyisobutylene but in a form not meeting primary forms definition
Subheading 3902.20.00 specifically covers polyisobutylene; if it meets the primary forms criteria, it would be classified there rather than as 'other'.
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 that the PIB is in primary forms (pellets, granules) and that isobutylene monomer content exceeds 95% by weight
• Maintain supplier certificates of analysis to support classification
• Check if the PIB qualifies as a synthetic rubber under Chapter 40, which may affect classification and duties
Related Products under Tariff item 3902.90.00
1-Hexene Polymer Pellets
1-Hexene Polymer Pellets are a homopolymer of 1-hexene in primary form, with more than 95% hexene units. Used in film applications, this olefin polymer falls under tariff item 3902.90.00 as an 'Other' polymer of olefins, since 1-hexene is not specifically named in heading 3902.
4-Methyl-1-Pentene Copolymer Pellets
4-Methyl-1-Pentene Copolymer Pellets are a copolymer where the named monomer, 4-methyl-1-pentene, predominates by weight. Used in high-temperature films and containers, these pellets fall under tariff item 3902.90.00 as 'Other' olefin polymers, since 4-methyl-1-pentene is not specifically named in heading 3902.
Butene-Propylene Random Copolymer Granules
Butene-Propylene Random Copolymer Granules are a random copolymer where butene predominates by weight over propylene. In primary form, these granules fall under tariff item 3902.90.00 as 'Other' olefin polymers, since butene is not specifically named in heading 3902.
Copolymer Polybutene PB-0300 MFI Pellets
Copolymer polybutene pellets with a melt flow index of 0.3 g/10min, used in film blowing applications. The butene monomer units predominate by weight, classifying it as a polymer of other olefins in primary forms under tariff item 3902.90.00.
Cyclic Olefin Copolymer COC Pellets
Cyclic Olefin Copolymer (COC) Pellets are made from norbornene and ethylene, with norbornene as the predominant monomer. Used in optical media and medical packaging, these pellets fall under tariff item 3902.90.00 as 'Other' olefin polymers, since norbornene is not specifically named in heading 3902.
Duraflex PB8400 Polybutene
Polybutene resin with medium melt flow index, designed for blow molding pipes. This primary form olefin polymer has butene as the predominant monomer, placing it under tariff item 3902.90.00 for other olefin polymers.