4002.19.00.16 - Styrene-butadiene rubber produced by solution polymerization (S-SBR) in bales

This HTS classification covers styrene-butadiene rubber (S-SBR) that has been produced through a solution polymerization process and is presented in bales. S-SBR is a synthetic rubber known for its specific properties derived from the styrene and butadiene monomers, and its production method by solution polymerization imparts characteristics distinct from rubbers produced by other methods. The "in bales" presentation signifies the common commercial form for this type of raw rubber material.

This category is distinguished from its siblings primarily by its specific production method and physical form. Unlike HTS 4002.19.00.14, which covers styrene-butadiene-styrene block copolymers in granular, crumb, or powder forms, this classification is for S-SBR in bales. Furthermore, it differs from HTS 4002.19.00.15, which specifically classifies styrene-butadiene rubber produced by emulsion polymerization (E-SBR) in bales, highlighting the crucial distinction between solution and emulsion polymerization methods for SBR.

As this is a leaf node within the HTS, there are no further subcategories. Therefore, the classification hinges on the precise identification of the material as styrene-butadiene rubber produced via solution polymerization and its presentation in bales. This ensures accurate differentiation from other forms of synthetic rubber or related copolymers that may share similar monomer compositions but differ in production process or final form.