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%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
• 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