Polyisobutylene Rubber PIB from Japan
Polyisobutylene (PIB) is a synthetic rubber polymer derived from isobutylene monomer, imported in primary pellet form under HTS 3902.90.0050 as 'other' olefin polymers. With isobutylene comprising over 95% by weight, it meets subheading note (a)(1) criteria. Used in chewing gum bases, adhesives, and sealants for its tackiness and impermeability.
Duty Rate — Japan → United States
12.5%
Rate breakdown
9903.05.4912.5%Section 301 (forced labor) — Japan (col1 rate < 12.5 percent): MFN < 12.5% → total duty capped at 12.5%
Import Tips
• Include FTIR or NMR test reports proving >95% isobutylene monomer content
• Label clearly as 'primary forms' to distinguish from compounded rubber products
• Check for copolymer content; excess may reclassify under predominant monomer rule