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1,3,5-Trioxane Crystals from China

1,3,5-Trioxane forms six-membered ring with three oxygen hetero-atoms from formaldehyde cyclization. Used in polymers despite chapter note exclusion reference. HTS 2932.99.90 as defined oxygen heterocycle.

Duty Rate — China → United States

16.2%

Rate breakdown

9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China

Import Tips

Acid stabilizer prevents depolymerization during shipping

Melting point 62°C confirms crystalline form

Distinguish from paraformaldehyde (Chapter 39)