Cyclized Rubber (Alkylated Chlorosulfonated Rubber) from Mexico
Cyclized rubber is produced by treating natural rubber with sulfuric acid or other agents to create cyclic structures, yielding a harder derivative used in paints and varnishes. It appears in primary flake or powder form. Falls under HTS 3913.90.1000 as a chemical derivative of natural rubber not elsewhere specified.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
Import Tips
• Submit chemical structure analysis proving cyclization of natural rubber polyisoprene to confirm 3913 classification
• Label clearly as 'primary form' to distinguish from finished articles in Chapter 40 or 39 headings
• Watch for misclassification as reclaimed rubber (4003) if processing involves devulcanization