Thiol-Terminated Polysulfide Prepolymer LP-3 from Mexico
Thiol-Terminated Polysulfide Prepolymer LP-3 is a viscous, elastomeric liquid used in aerospace sealants and coatings. Classified under HTS 3911.90.10.00 for elastomeric polysulfides in primary forms per subheading rules on polymer content. Its mercaptan-terminated structure provides elasticity for high-performance applications.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
Import Tips
• Submit technical data sheets proving >95% polysulfide monomer content to qualify under 3911.90.10
• Avoid misdeclaration as rubber by confirming it's unvulcanized primary form, not Chapter 40 material