Chapter 39 covers plastics and articles thereof, including polymers in primary forms, semi-manufactures, and finished products. This chapter is divided by polymer type, such as polyethylene, polypropylene, polysiloxanes, etc. Primary forms refer to liquid, paste, block, powder, granule, and similar forms, excluding shaped or further processed products. The chapter notes provide detailed provisions on the definition of 'plastics', the scope of processing, and the distinction from other chapters, which form the basis for classification. Heading 3910 specifically refers to polysiloxanes (silicones) in primary forms, including liquid silicone rubber, silicone oil, silicone resin, etc. Polysiloxanes are polymers with a siloxane bond backbone and organic groups as side chains, featuring high and low temperature resistance, electrical insulation, hydrophobicity, and other properties. This heading covers all primary forms, such as emulsions, solutions, dispersions, etc., but excludes silicone rubber articles (such as tubes, sheets) or silicone oil articles (such as lubricant additives), which are generally classified under other headings. Code 391000 is a six-digit subheading: the first two digits '39' represent Chapter 39 (plastics and articles thereof); digits 3-4 '10' represent heading 3910 (polysiloxanes in primary forms); digits 5-6 '00' indicate that there is no further subdivision under this heading, i.e., all polysiloxanes in primary forms are classified under this subheading. Therefore, the full meaning of 391000 is 'polysiloxanes in primary forms', regardless of their specific type (silicone oil, silicone rubber, silicone resin) or form (liquid, powder, granule), as long as they meet the definition of primary forms, they are classified under this code. The goods are polysiloxanes, which are organosilicon polymers and meet the definition of plastics in Chapter 39. Since they are in primary forms and heading 3910 explicitly names 'polysiloxanes', they are classified under 391000. They are not classified under other headings such as 3911 (petroleum resins) or 3909 (amino-resins) because of different chemical structures; nor under Chapter 40 (rubber) because polysiloxanes are not traditional rubber, and Chapter 39 notes have specific provisions.
Chapter
Chapter 39 covers plastics and articles thereof, including polymers in primary forms, semi-manufactures, and finished products. This chapter is divided by polymer type, such as polyethylene, polypropylene, polysiloxanes, etc. Primary forms refer to liquid, paste, block, powder, granule, and similar forms, excluding shaped or further processed products. The chapter notes provide detailed provisions on the definition of 'plastics', the scope of processing, and the distinction from other chapters, which form the basis for classification.
Heading
Heading 3910 specifically refers to polysiloxanes (silicones) in primary forms, including liquid silicone rubber, silicone oil, silicone resin, etc. Polysiloxanes are polymers with a siloxane bond backbone and organic groups as side chains, featuring high and low temperature resistance, electrical insulation, hydrophobicity, and other properties. This heading covers all primary forms, such as emulsions, solutions, dispersions, etc., but excludes silicone rubber articles (such as tubes, sheets) or silicone oil articles (such as lubricant additives), which are generally classified under other headings.
Digit Breakdown
Code 391000 is a six-digit subheading: the first two digits '39' represent Chapter 39 (plastics and articles thereof); digits 3-4 '10' represent heading 3910 (polysiloxanes in primary forms); digits 5-6 '00' indicate that there is no further subdivision under this heading, i.e., all polysiloxanes in primary forms are classified under this subheading. Therefore, the full meaning of 391000 is 'polysiloxanes in primary forms', regardless of their specific type (silicone oil, silicone rubber, silicone resin) or form (liquid, powder, granule), as long as they meet the definition of primary forms, they are classified under this code.
Classification Basis
The goods are polysiloxanes, which are organosilicon polymers and meet the definition of plastics in Chapter 39. Since they are in primary forms and heading 3910 explicitly names 'polysiloxanes', they are classified under 391000. They are not classified under other headings such as 3911 (petroleum resins) or 3909 (amino-resins) because of different chemical structures; nor under Chapter 40 (rubber) because polysiloxanes are not traditional rubber, and Chapter 39 notes have specific provisions.
📝 Declaration Elements
Product Name: The specific name of the declared goods, such as silicone oil, silicone rubber, silicone resin, etc., which must be consistent with the actual product. Appearance: Describe the physical state of the primary form, such as liquid, powder, granule, block, etc. Composition and Content: Main components and content, such as polydimethylsiloxane content ≥95%, solvent or additive proportions. Use: Explain the main use of the goods, such as lubrication, sealing, mold release, insulation, etc. Brand: Manufacturer or trader brand; if no brand, indicate 'no brand'. Model: Product model or specifications, such as viscosity, molecular weight, and other parameters. Packaging Specifications: Packaging form and net weight, such as iron drum, 200kg/drum. Product Name: Polydimethylsiloxane (silicone oil); Appearance: Colorless transparent liquid; Composition and Content: Polydimethylsiloxane 99.5%, water 0.5%; Use: For insulation of electronic components; Brand: Dow Corning; Model: DC-200, viscosity 1000cSt; Packaging Specifications: 200kg/iron drum. Mistakenly declaring silicone rubber articles (such as sealing rings) as primary forms, which should actually be classified under other headings. Failure to distinguish silicone oil from silicone resin; although both belong to 391000, declaration elements should be accurate. Ignoring solvent content; if polysiloxane is dissolved in organic solvents, it is still classified under 391000, but the solvent must be indicated.
Product Name
The specific name of the declared goods, such as silicone oil, silicone rubber, silicone resin, etc., which must be consistent with the actual product.
⚠️ Writing only 'polysiloxane' without specification, or mistakenly writing 'silica gel' leading to classification disputes.
Appearance
Describe the physical state of the primary form, such as liquid, powder, granule, block, etc.
⚠️ Describing articles (such as silicone tubes) as primary forms, leading to classification errors.
Composition and Content
Main components and content, such as polydimethylsiloxane content ≥95%, solvent or additive proportions.
⚠️ Not indicating solvent content, mistakenly classifying solutions under other headings.
Use
Explain the main use of the goods, such as lubrication, sealing, mold release, insulation, etc.
⚠️ Use description is too broad, such as 'industrial use', which cannot assist classification.
Brand
Manufacturer or trader brand; if no brand, indicate 'no brand'.
⚠️ Brand inconsistent with the actual product, or omitting the brand.
Model
Product model or specifications, such as viscosity, molecular weight, and other parameters.
⚠️ Incomplete model filling, resulting in inability to distinguish different products.
Packaging Specifications
Packaging form and net weight, such as iron drum, 200kg/drum.
⚠️ Packaging specifications inconsistent with the declared quantity unit.
Example： Product Name: Polydimethylsiloxane (silicone oil); Appearance: Colorless transparent liquid; Composition and Content: Polydimethylsiloxane 99.5%, water 0.5%; Use: For insulation of electronic components; Brand: Dow Corning; Model: DC-200, viscosity 1000cSt; Packaging Specifications: 200kg/iron drum.
Common Mistakes：
Mistakenly declaring silicone rubber articles (such as sealing rings) as primary forms, which should actually be classified under other headings.
Failure to distinguish silicone oil from silicone resin; although both belong to 391000, declaration elements should be accurate.
Ignoring solvent content; if polysiloxane is dissolved in organic solvents, it is still classified under 391000, but the solvent must be indicated.
🎯 Classification Logic
Core classification basis: 1. The goods are polysiloxanes, meeting the definition of plastics in Chapter 39; 2. The form is primary (liquid, powder, etc.), not further processed; 3. Heading 3910 explicitly names them. Reference should be made to the Explanatory Notes on 'primary forms' and 'polysiloxanes', as well as the chapter notes on the scope of plastics. If the goods are silicone rubber articles, they are classified under Chapter 40 or other headings of Chapter 39. 391000 Polysiloxanes in primary forms: This code is the same as 391000, but note that 391000 is the only subheading with no further subdivision. 391190 Other synthetic polymers in primary forms: 391190 covers synthetic polymers not elsewhere specified, while polysiloxanes are already named under 3910, so they are not classified under 391190. 400299 Other synthetic rubber in primary forms: If polysiloxanes are in rubber form, they might be classified under 400299, but according to chapter notes, polysiloxanes are classified under Chapter 39. 340319 Lubricants: If silicone oil is used as a lubricant, it depends on whether it is in primary form; if it is a preparation, it is classified under 3403; if it is pure silicone oil, it is classified under 3910. 382499 Other chemical industry products: If polysiloxanes are preparations, they might be classified under 3824, but pure polysiloxanes in primary forms are classified under 3910. Is it in primary form (liquid, powder, granule, etc.)? Does it belong to polysiloxanes (siloxane bond backbone)? Has it been further processed into articles? Is it mixed with other substances into preparations? Is it explicitly named under 3910?
Basis
Core classification basis: 1. The goods are polysiloxanes, meeting the definition of plastics in Chapter 39; 2. The form is primary (liquid, powder, etc.), not further processed; 3. Heading 3910 explicitly names them. Reference should be made to the Explanatory Notes on 'primary forms' and 'polysiloxanes', as well as the chapter notes on the scope of plastics. If the goods are silicone rubber articles, they are classified under Chapter 40 or other headings of Chapter 39.
Confused Codes：
391000 - Polysiloxanes in primary forms
This code is the same as 391000, but note that 391000 is the only subheading with no further subdivision.
391190 - Other synthetic polymers in primary forms
391190 covers synthetic polymers not elsewhere specified, while polysiloxanes are already named under 3910, so they are not classified under 391190.
400299 - Other synthetic rubber in primary forms
If polysiloxanes are in rubber form, they might be classified under 400299, but according to chapter notes, polysiloxanes are classified under Chapter 39.
340319 - Lubricants
If silicone oil is used as a lubricant, it depends on whether it is in primary form; if it is a preparation, it is classified under 3403; if it is pure silicone oil, it is classified under 3910.
382499 - Other chemical industry products
If polysiloxanes are preparations, they might be classified under 3824, but pure polysiloxanes in primary forms are classified under 3910.
Self-Check：
✓ Is it in primary form (liquid, powder, granule, etc.)?
✓ Does it belong to polysiloxanes (siloxane bond backbone)?
✓ Has it been further processed into articles?
✓ Is it mixed with other substances into preparations?
✓ Is it explicitly named under 3910?
❓ FAQ
How to inquire about the tariff rate for 391000? You can inquire through the official website of the General Administration of Customs, China International Trade Single Window, or the 'Import and Export Tariff of the People's Republic of China'. Enter HS code 391000 to view the MFN rate, general rate, VAT rate, and regulatory conditions. Note that rates may be adjusted with policy changes; it is recommended to refer to the latest announcements. Are silicone oil and silicone rubber both classified under 391000? Yes, as long as they are polysiloxanes in primary forms, whether silicone oil, silicone rubber, or silicone resin, they are all classified under 391000. However, if they have been processed into articles (such as silicone tubes, sealing rings), they are classified under other headings, such as Chapter 40 or other headings of Chapter 39. How should polysiloxane solutions be declared? If polysiloxanes are dissolved in organic solvents and the solvent is volatile, they are still classified as polysiloxanes under 391000. When declaring, the solvent name and content must be indicated. If the solvent makes the product a preparation, it may be classified under other headings. How to distinguish between 391000 and 391190? 391000 specifically refers to polysiloxanes, while 391190 is for other synthetic polymers not elsewhere specified. If the goods are polysiloxanes, they must be classified under 391000, not 391190. The key distinction lies in the chemical structure: polysiloxanes contain a siloxane bond backbone. What regulatory documents are required for importing polysiloxanes? Generally, basic documents such as contract, invoice, packing list, and bill of lading are required. Depending on the use, an MSDS (Material Safety Data Sheet) may be required. Some polysiloxanes may involve hazardous chemicals, requiring hazardous chemical registration. Specific regulatory conditions are subject to the latest customs regulations. What code applies to cross-border e-commerce retail import of polysiloxanes? Cross-border e-commerce retail imports also use HS code 391000. However, note that personal items have amount limits and must comply with the cross-border e-commerce retail import commodity list. If the limit is exceeded, general trade customs declaration is required. How to describe the use of polysiloxanes when declaring? The use should be specific, such as 'for insulation of electronic components', 'for cosmetic additives', 'for mold release agents', etc. Avoid general descriptions like 'industrial use'. The use helps customs determine classification, but the final classification is based on composition and form. Is the classification of polysiloxanes affected by packaging? Packaging does not affect classification, but packaging specifications must be declared. Whether in large drums or small bottles, as long as the goods themselves are polysiloxanes in primary forms, they are classified under 391000. However, if the packaging is for retail sale and the contents are articles, it may affect classification.
Q: How to inquire about the tariff rate for 391000?
A: You can inquire through the official website of the General Administration of Customs, China International Trade Single Window, or the 'Import and Export Tariff of the People's Republic of China'. Enter HS code 391000 to view the MFN rate, general rate, VAT rate, and regulatory conditions. Note that rates may be adjusted with policy changes; it is recommended to refer to the latest announcements.
Q: Are silicone oil and silicone rubber both classified under 391000?
A: Yes, as long as they are polysiloxanes in primary forms, whether silicone oil, silicone rubber, or silicone resin, they are all classified under 391000. However, if they have been processed into articles (such as silicone tubes, sealing rings), they are classified under other headings, such as Chapter 40 or other headings of Chapter 39.
Q: How should polysiloxane solutions be declared?
A: If polysiloxanes are dissolved in organic solvents and the solvent is volatile, they are still classified as polysiloxanes under 391000. When declaring, the solvent name and content must be indicated. If the solvent makes the product a preparation, it may be classified under other headings.
Q: How to distinguish between 391000 and 391190?
A: 391000 specifically refers to polysiloxanes, while 391190 is for other synthetic polymers not elsewhere specified. If the goods are polysiloxanes, they must be classified under 391000, not 391190. The key distinction lies in the chemical structure: polysiloxanes contain a siloxane bond backbone.
Q: What regulatory documents are required for importing polysiloxanes?
A: Generally, basic documents such as contract, invoice, packing list, and bill of lading are required. Depending on the use, an MSDS (Material Safety Data Sheet) may be required. Some polysiloxanes may involve hazardous chemicals, requiring hazardous chemical registration. Specific regulatory conditions are subject to the latest customs regulations.
Q: What code applies to cross-border e-commerce retail import of polysiloxanes?
A: Cross-border e-commerce retail imports also use HS code 391000. However, note that personal items have amount limits and must comply with the cross-border e-commerce retail import commodity list. If the limit is exceeded, general trade customs declaration is required.
Q: How to describe the use of polysiloxanes when declaring?
A: The use should be specific, such as 'for insulation of electronic components', 'for cosmetic additives', 'for mold release agents', etc. Avoid general descriptions like 'industrial use'. The use helps customs determine classification, but the final classification is based on composition and form.
Q: Is the classification of polysiloxanes affected by packaging?
A: Packaging does not affect classification, but packaging specifications must be declared. Whether in large drums or small bottles, as long as the goods themselves are polysiloxanes in primary forms, they are classified under 391000. However, if the packaging is for retail sale and the contents are articles, it may affect classification.
⚠️ Disclaimer: HS code classification, declaration elements, tariff rates and regulatory conditions on this page are for reference only and do not constitute legal advice on customs classification. Tariff rates and regulations are subject to change; the latest announcements from the General Administration of Customs and on-site determinations shall prevail. Please consult professional customs brokers or customs authorities before import/export.