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
12.5%
Rate breakdown
9903.05.4912.5%Section 301 (forced labor) — Japan (col1 rate < 12.5 percent): MFN < 12.5% → total duty capped at 12.5%
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