Product classification
HS code for Polyisobutylene: 3902.20
Propylene, other olefin polymers, polyisobutylene in primary forms.
Classification of polyisobutylene under HS 3902.20
Polyisobutylene (PIB) is classified under HS code 3902.20. This classification falls within Chapter 39 (Plastics and articles thereof) and heading 3902, which covers polymers of propylene or of other olefins in primary forms. Polyisobutylene is a synthetic hydrocarbon polymer produced by the polymerization of isobutylene. The term "primary forms" is strictly defined in Note 6 to Chapter 39 and includes liquids, pastes, dispersions, solutions, and blocks of irregular shape, granules, or powders. PIB is widely used in the production of adhesives, sealants, and as an additive in fuels and lubricants. Because it is a polymer of an olefin (isobutylene) and is typically traded in bulk liquid or semi-solid forms, it is specifically assigned to the 3902.20 subheading. The classification remains consistent regardless of the molecular weight, provided it remains a homopolymer of isobutylene.
- Covers
- Liquid polyisobutylene (low molecular weight)
- Semi-solid PIB resins
- PIB used as a viscosity index improver
- Polyisobutylene in primary blocks or lumps
- High molecular weight PIB for adhesive bases
- Also under 3902.20
- BASF Oppanol
- ExxonMobil Vistanex
- Lanxess Krynac
- TPC Polybutene
- INEOS Oronite
Codes often confused with 3902.20
Common mistake. Polyisobutylene is often confused with HS code 4002.31 or 4002.39, which cover halo-isobutene-isoprene rubber (CIIR or BIIR) and butyl rubber (IIR). While PIB is chemically related to butyl rubber, Chapter 40 is reserved for synthetic rubber that can be vulcanized. Pure polyisobutylene cannot be vulcanized in the same manner as butyl rubber and therefore must stay in Chapter 39. Another misclassification occurs in 3811.21, where PIB-based lubricant additives are sometimes placed; however, pure PIB in primary form belongs in 3902.20.
Top exporters and importers of HS 390220 (the code used for polyisobutylene), 2025
In 2025, the largest exporter of HS 390220 (the code used for polyisobutylene) in UN Comtrade data was South Korea, with 28% of world exports; the largest importer in UN Comtrade data was China, with 19% of world imports. Countries that did not report 2025 data are estimated from partner records, which can understate them.
Figures cover everything classified under HS 390220, not only polyisobutylene.
Top exporters 2025 · share of world exports
- 1 South Korea $329M 28% of world exports
- 2 United States $158M 14% of world exports
- 3 Belgium $156M 13% of world exports
World total: $1.2B Reported figures on UN Comtrade ↗
Top importers 2025 · share of world imports
- 1 China $226M 19% of world imports
- 2 France $148M 13% of world imports
- 3 Singapore $130M 11% of world imports
World total: $1.2B Reported figures on UN Comtrade ↗
How these figures are built
109 countries reported 2025 trade to UN Comtrade in HS 2022, and their own totals are used. Countries that did not report are estimated from what other countries recorded trading with them. Those estimates miss trade with other non-reporting countries, so they can be low, and a non-reporting country can rank higher than shown or be missing from the list. World totals add both and leave out trade between two non-reporting countries. Figures are in current US dollars; reported imports are mostly valued CIF and exports FOB, and exports include re-exports. The UN Comtrade links show the underlying records; they can also list a few reporters left out here (regional groups and older HS editions).
Source: UN Comtrade (United Nations Statistics Division), 2025 annual data.
Brazil NCM code for polyisobutylene
Brazil classifies polyisobutylene under NCM 3902.20.00: HS 3902.20 with 00 added.
Source: Siscomex NCM table, updated Oct 2026. The Portuguese text on each NCM page is the official one.
Questions about polyisobutylene
What is the HS code for Polyisobutylene?
The HS code for Polyisobutylene is 390220 (Propylene, other olefin polymers; polyisobutylene in primary forms). The HS code for polyisobutylene in primary forms is 3902.20.
How do I classify Polyisobutylene for customs?
Polyisobutylene is classified under HS code 390220 — Propylene, other olefin polymers; polyisobutylene in primary forms. This is a 6-digit subheading level code.
Is polyisobutylene classified as a rubber?
No, polyisobutylene is classified as a plastic under 3902.20, whereas butyl rubber (a copolymer) is classified under 4002.
Which countries are the top exporters of polyisobutylene (HS 390220)?
In 2025, the top exporters of HS 390220 (the code used for polyisobutylene) in UN Comtrade data were South Korea ($329M, 28% of world exports), the United States ($158M) and Belgium ($156M). World exports came to about $1.2B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Which countries are the top importers of polyisobutylene (HS 390220)?
In 2025, the top importers of HS 390220 (the code used for polyisobutylene) in UN Comtrade data were China ($226M, 19% of world imports), France ($148M) and Singapore ($130M). World imports came to about $1.2B, adding countries' reported figures and partner-based estimates for those that did not report (UN Comtrade data). Countries that did not report 2025 data are estimated from partner records, which can understate them.
Is the HS code for Polyisobutylene the same in all countries?
The base HS code 390220 for Polyisobutylene is internationally standardized for the first 6 digits across 200+ countries. Individual countries may add additional digits for national tariff lines and specific classifications.
What is the NCM code for polyisobutylene in Brazil?
In Brazil, polyisobutylene (HS 390220) is classified under NCM 3902.20.00.