3902.10.00.00 - Polypropylene

This HTS category, 3902.10.00.00, specifically covers polypropylene when it is in its primary forms. Primary forms, as defined by Chapter 39 of the Harmonized Tariff Schedule, generally refer to liquids and pastes, including dispersions, solutions, and emulsions, as well as powders, granules, lumps, flakes, and blocks. Therefore, this classification applies to bulk polypropylene materials that have not yet undergone further processing into articles, such as films, sheets, or molded goods.

Distinguishing this category from its siblings, 3902.20 covers polyisobutylene, which is a distinct polymer of isobutylene. 3902.30.00.00 is for propylene copolymers, meaning materials that are made from both propylene and at least one other olefin. Finally, 3902.90.00 encompasses "other" polymers of propylene or other olefins not specifically enumerated in the preceding headings of 3902, making it a residual category for less common or specifically defined olefin polymers. This heading, 3902.10.00.00, is exclusively for homopolymer polypropylene.

As this is a leaf node within the HTS structure, there are no further subcategories under 3902.10.00.00. Classification at this level focuses solely on identifying the material as polypropylene in its primary form, distinct from other polymers of propylene or other olefins or any processed articles made from such materials. Practical classification criteria would include the chemical composition and physical state of the material as imported or exported.