HDI Biuret Trimer (Desmodur N 100)
HDI Biuret trimer is a high-functionality polyisocyanate derived from 1,6-hexamethylene diisocyanate, containing residual monomeric HDI (<0.25%). It qualifies under HTS 2929.10.3500 as an isocyanate per Chapter notes allowing derivatives of listed compounds. Primarily used as crosslinking agent in durable industrial coatings.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If diluted in >30% solvent for spray application rather than pure reactive form
Chapter note (e) excludes solutions 'particularly suitable for specific use' from Chapter 29
If polymerized beyond reactive isocyanate stage into polyurethane polyisocyanate resin
Advanced polymerization changes from low-MW isocyanate (2929) to polymer (Ch.39)
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right HTS code — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Provide analytical certificate showing NCO content (typically 21-22%) and residual monomer <0.3% to confirm isocyanate identity
• Moisture exclusion critical—use nitrogen-blanketed containers to prevent gelling during ocean transit
• Avoid classification disputes by documenting it's not a 'finished coating' (3208/3209) but reactive intermediate
Related Products under HTS 2929.10.35.00
1,6-Hexamethylene Diisocyanate (HDI)
1,6-Hexamethylene diisocyanate (HDI) is a chemically defined aliphatic diisocyanate with the formula OCNC6H12NCO, used primarily as a reactive intermediate in polyurethane production. It falls under HTS 2929.10.3500 as an isocyanate compound with other nitrogen function, specifically named in the tariff schedule. This clear, colorless liquid is essential for creating durable coatings and adhesives.
Desmodur H Diisocyanate
Desmodur H is the commercial trade name for high-purity 1,6-hexamethylene diisocyanate (HDI) produced by Covestro, stabilized with <0.1% benzoyl chloride for transport. Classed under HTS 2929.10.3500 as the specifically named isocyanate per Chapter 29 notes (f) allowing stabilizers. Used in two-component polyurethane paints for automotive clearcoats.
Monodisperse HDI (Purified 99.5%)
Laboratory-grade 1,6-hexamethylene diisocyanate with 99.5% purity, minimal isomeric impurities, packaged in 1-5kg quantities for R&D. Falls squarely under HTS 2929.10.3500 as chemically defined isocyanate per Chapter note (a). Used in synthesis of biomedical polyurethanes and adhesives.
HDI Stabilized with 0.02% HDB Catapult
Industrial 1,6-hexamethylene diisocyanate stabilized with proprietary 0.02% HDB Catapult additive to prevent yellowing during storage. HTS 2929.10.3500 applies per Chapter note (f) for added stabilizers necessary for transport. Standard for non-yellowing wood floor coatings.