Isotactic Polybutene Granules from Japan
Isotactic polybutene granules, a stereoregular polymer of butene with high crystallinity, fall under HTS 3902.90.0050 as 'other' primary olefin polymers (>95% butene content). Used in films and molded parts for its strength and chemical resistance. Classified per note (a)(1) for named poly- prefixes.
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 stereochemistry details in technical data sheets for CBP review
• Segregate from polyethylene shipments to prevent co-mingling errors
• Watch for moisture content affecting primary form integrity