Polyisobutylene Rubber PIB from Mexico
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 — Mexico → United States
16.5%
Rate breakdown
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
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