Liquefied Isobutylene (2-Methylpropene) from China
Liquefied isobutylene, an unsaturated C4 olefin used in methyl methacrylate and butyl rubber production. Covered by HTS 2711.14.00 as liquefied butylene (including branched isomers).
Duty Rate — China → United States
25%
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)
9903.05.860%Articles provided for in subdivision (b) of U.S. note 52 to this subchapter
Import Tips
• Document isobutylene >95% via mass spectrometry to distinguish from isobutane
• Ship in dedicated C4 olefin spheres with polymerization inhibitors