Isobutylene from China
Isobutylene (2-methylpropene, C4H8) is a branched unsaturated hydrocarbon from petroleum refinery C4 streams. HTS 2901.29.1050 applies as 'other' petroleum-derived acyclic unsaturated hydrocarbon, separated via extractive distillation. Primary use in butyl rubber and methacrylate production.
Duty Rate — China → United States
37.5%
Rate breakdown
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China
Import Tips
• Typically imported refrigerated (-7°C) or as 55% aqueous solution; specify physical form
• UN1055, Hazard Class 2.1; ensure proper cylinder valve protection for refrigerated liquid
• Avoid confusion with 1-butene; CAS 75-28-5 and branched structure confirmation required