3911.90.91.50/Polyimide Prepolymer Powder/Japan

Polyimide Prepolymer Powder from Japan

Thermosetting polyimide prepolymer powder in primary form for aerospace composites. Under 3911.90.91.50 as NES thermosetting product, classified by predominant imide monomer units.

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%

Calculate with your customs value Verify classification with AI

Import Tips

• Include cure cycle instructions proving thermoset transformation from prepolymer state

• Test for 95% imide content to rule out copolymer shifts per subheading note (a)(2)

• Comply with ITAR if for defense applications; separate from tariff classification