Prehnitic Acid from Japan
Prehnitic acid (benzene-1,2,4,5-tetracarboxylic acid) used in polyimide films and high-performance composites. Identical reactivity to pyromellitic acid but different substitution pattern. HTS 2917.39.70.00 as aromatic polycarboxylic acid, other.
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
• Synonymous with pyromellitic acid in commerce; position isomers rarely distinguished
• Composite prepreg manufacturers require lot-specific DSC thermal analysis
• Distinguish monomer from Chapter 39 low MW prepolymer by GPC analysis