Other Styrene Polymers in Primary Forms (N.E.S.)

A detailed certificate of analysis identifying the comonomer(s), their weight percentages, and the absence of butadiene (which would indicate ABS) or acrylonitrile alone (which would indicate SAN) is essential. A binding ruling from CBP is advisable for novel copolymer formulations to avoid reclassification risk.

Potentially, but the classification depends on whether the material is considered a styrene polymer or a synthetic rubber under the applicable nomenclature rules. Thermoplastic elastomers with high butadiene content may be classified under rubber headings rather than plastics headings. A licensed customs broker should review the specific polymer architecture and composition before import.