Dioxolane Monomer from Japan
1,3-Dioxolane features a five-membered ring with two oxygen hetero-atoms, used as comonomer in polyacetal resin production and pharma intermediates. Pure monomer form qualifies as heterocyclic oxygen compound under HTS 2932.99.90.90. Excluded from cyclic ester provisions by Chapter note 5.
Duty Rate — Japan → United States
23.8%
Rate breakdown
9903.04.6211.3%Patented pharmaceutical articles that are the product of Japan, of a European Union member country, of South Korea, of Switzerland, or of Liechtenstein as provided for in subdivisions (c) and (f) of U.S. note 40 to this subchapter
9903.05.4912.5%Except for products described in headings 9903.05.85–9903.05.92, articles the product of Japan, with an ad valorem (or ad valorem equivalent) rate of duty under column 1 less than 12.5 percent, as provided for in U.S. note 52 to this subchapter
Import Tips
• Polymerization inhibitor content <50ppm required to maintain monomer classification
• Formaldehyde residual limits <0.1% prevent reclassification as formaldehyde derivative
• Glass-lined containers mandatory for moisture-sensitive dioxolane shipments