Silicones in primary forms
Silicones in primary forms
Duty Rate (from China)
Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
Except as provided in headings 9903.88.12, 9903.88.17, 9903.88.20, 9903.88.54, 9903.88.59, 9903.88.61, 9903.88.63, 9903.88.66, 9903.88.67, 9903.88.68, 9903.88.69, or 9903.88.70, articles the product of China, as provided for in U.S. note 20(c) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(d)
Products classified under HTS 3910.00.00.00
Polydimethylsiloxane (PDMS) Fluid
Polydimethylsiloxane (PDMS) is a clear, viscous silicone polymer fluid used in lubricants, cosmetics, and as a release agent. It falls under HTS 3910.00.00.00 as a silicone in primary form, where the siloxane monomer units constitute 95% or more by weight of the polymer content per chapter notes.
Silicone Resin in Solid Form
Silicone resin is a heat-resistant, solid silicone polymer used in coatings and electrical insulators. Classified under HTS 3910.00.00.00 as silicones in primary forms, meeting the 95% siloxane monomer requirement per subheading notes.
Hydroxy-Terminated Polydimethylsiloxane
Hydroxy-terminated PDMS is a reactive silicone fluid used in sealants and adhesives production. It qualifies under HTS 3910.00.00.00 as a primary form silicone per note (a)(3) for chemically modified polymers not more specifically covered.
Amino-Modified Silicone Fluid
Amino-modified silicone fluid enhances adhesion in textiles and hair care products. Falls under HTS 3910.00.00.00 as chemically modified silicones in primary form, compliant with Chapter 39 polymer classification rules.
Vinyl-Functional Silicone Polymer
Vinyl-terminated silicone polymers are crosslinking agents for RTV silicones. Classified in HTS 3910.00.00.00 as primary silicones where siloxane units exceed 95% by weight.
Phenyl-Modified Silicone Oil
Phenyl-modified silicone oil offers high thermal stability for transformer fluids. HTS 3910.00.00.00 applies as primary silicone per note (a)(3) for modified polymers.
Fluorosilicone Polymer Gum
Fluorosilicone gum stock is used in aerospace seals requiring fuel resistance. Primary form classification under HTS 3910.00.00.00 when fluoroalkyl siloxane monomers predominate.
Silicone Elastomer Base Uncured
Uncured silicone elastomer base contains silica filler and peroxide catalyst. Still classified as primary form under HTS 3910.00.00.00 if polymer content predominates per notes.