Chlorobutyl Rubber (CIIR)
Chlorinated isobutylene-isoprene rubber (CIIR) in primary pellet or bale form, where chlorinated monomer units predominate >95% by weight. Widely used in tire inner liners and pharmaceutical stoppers for air impermeability. Classified in 3911.90.70.00 as chlorinated synthetic rubber.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If unchlorinated isobutylene-isoprene rubber
Non-chlorinated butyl rubber remains in Chapter 40 synthetic rubbers.
If blends with <95% chlorinated content
Subheading note (a)(4) directs to predominant monomer subheading if purity threshold unmet.
If supplied in plates/sheets for retail
Non-primary forms like sheets classify as other plastic plates under 3920.
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Import Tips & Compliance
• Include monomer weight breakdown certificate to satisfy note (a)(1) 'poly' designation rules
• Label as 'primary form' explicitly; compounded versions risk moving to 3926.90
• Avoid misdeclaration as regular butyl (4002.31); chlorination shifts to Chapter 39
Related Products under HTS 3911.90.70.00
Hypalon Chlorinated Rubber (CSM-20)
Chlorosulfonated polyethylene (Hypalon CSM-20), a chlorinated synthetic rubber with >95% polyethylene-derived chlorinated units. Excels in chemical-resistant hoses and cables. Primary form classification under 3911.90.70.00.
Chlorinated Styrene-Butadiene Rubber (Cl-SBR)
Chlorinated copolymer of styrene-butadiene rubber, meeting 95% chlorinated unit threshold. Used in tire treads and conveyor belts for enhanced adhesion. 3911.90.70.00 for this primary chlorinated synthetic rubber.
Baymod CN Chlorinated Rubber
Commercial chlorinated synthetic rubber resin (Baymod CN series) from chlorination of natural/synthetic base, >95% purity. For marine coatings and adhesives. HTS 3911.90.70.00 applies.
Chlorinated Polyisoprene Rubber (Cl-IR)
Chlorinated synthetic polyisoprene rubber in latex or solid form, predominant chlorinated units. Used in medical gloves and seals. Primary form under 3911.90.70.00.
Permalyn Chlorinated Resin
Chlorinated terpene-phenolic synthetic rubber resin for adhesives. 95%+ chlorinated content. 3911.90.70.00.
Cloroprene Chlorinated Elastomer
Specialty chlorinated neoprene elastomer powder for coatings. Primary form, HTS 3911.90.70.00.