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Spiro Phosphonate Monomer for Polymer Synthesis from Mexico

This research-grade spiro phosphonate monomer, chemically 3,9-dimethyl-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane 3,9-dioxide, is used in copolymer production. It qualifies under HTS 2931.48.00.00 for its organo-inorganic phosphorus structure excluding halogens.

Duty Rate — Mexico → United States

13.7%

Rate breakdown

9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico

Import Tips

Request Certificate of Analysis (CoA) specifying >98% purity to meet 'chemically defined' criteria

Segregate from solvents to avoid note (e) issues

Monitor REACH-like regulations for phosphorus compounds