Polybutene-1 Resin PB-1 from China

Polybutene-1 (PB-1) is a high-molecular-weight polymer of butene-1, classified under HTS 3902.90.0050 as an 'other' olefin polymer in primary form (pellets or granules) where the butene-1 monomer exceeds 95% by weight. It is used in sealants, hot-melt adhesives, and pipe applications due to its flexibility and sealing properties. This falls into the 'Other' subheading after specific polypropylene and ethylene copolymers.

Duty Rate — China → United States

31.5%

Rate breakdown

9903.88.0225%Except as provided in headings 9903.88.12, 9903.88.17, 9903.88.20, 9903.88.54, 9903.88.59, 9903.88.61, 9903.88.63, 9903.88.66, 9903.88.67, 9903.88.68, 9903.88.69, or 9903.88.70, articles the product of China, as provided for in U.S. note 20(c) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(d)
9903.03.030%Articles the product of any country, as provided for in subdivision (aa)(ii) of U.S. note 2 to this subchapter

Import Tips

Verify monomer composition via lab analysis to confirm >95% butene-1 content for 3902 classification

Provide supplier certificates showing primary form (granules/pellets) and no chemical modification

Avoid misclassification as polyethylene by detailing predominant monomer in documentation