Chapter 39 covers plastics and articles thereof, and is a core chapter in the HS classification organized by material properties. This chapter includes polymers in primary forms (such as resins and pellets), as well as semi-finished and finished products (such as plates, sheets, tubes, and packaging containers). Within the chapter, further subdivision is based on polymer type (such as polyethylene, polypropylene, polymethyl methacrylate, etc.) and processing stage (primary forms, waste and scrap, semi-manufactures, articles). To understand this chapter, note that primary forms refer to liquids, pastes, blocks, powders, granules, and similar forms that have not undergone further processing, and they must meet the definition of 'plastics' in the notes. Heading 3906 covers acrylic polymers in primary forms, including polymethyl methacrylate (PMMA) and other acrylic polymers (such as polyacrylic acid and acrylic copolymers). Under this heading, further subdivision is based on polymer type and form: 3906.10 is polymethyl methacrylate, and 3906.90 is other acrylic polymers. Primary forms include liquid, paste, block, powder, granule, and flake forms, but do not include semi-finished or finished products already made into plates, sheets, film, tubes, etc., which are classified under subsequent headings. Code 390610 has 6 digits: the first 2 digits '39' represent Chapter 39 (plastics and articles thereof); digits 3-4 '06' represent heading 3906 (acrylic polymers in primary forms); digits 5-6 '10' represent subheading 3906.10 (polymethyl methacrylate). Therefore, the full meaning of 390610 is 'polymethyl methacrylate in primary forms.' Note: if PMMA is copolymerized with other monomers and the PMMA monomer unit does not predominate in the copolymer, it may be classified under 3906.90; if it has been processed into plates, sheets, etc., it is classified under 3916 or 3920, etc. The goods are polymethyl methacrylate in primary forms, whose chemical structure is a homopolymer of methyl methacrylate, meeting the description of 3906.10. If it is an acrylate copolymer (such as MMA copolymerized with styrene) and the MMA unit does not predominate, it is classified under 3906.90; if it is another polymer such as polyethylene, it is classified under 3901-3905; if it has been made into semi-finished products such as plates or sheets, it is classified under 3916 or 3920. Therefore, correct classification requires confirming the polymer type, monomer unit ratio, and physical form.

Product Name: The specific name of the declared commodity, such as 'polymethyl methacrylate (PMMA)'; common names such as 'acrylic' should be avoided. Appearance: Describe the physical form of the primary form, such as transparent granules, powder, liquid, etc., and it must be consistent with the declared elements. Composition and Content: State the content of polymethyl methacrylate (usually >=95%), and whether additives are contained (such as pigments and plasticizers). Types and Proportions of Monomer Units: For copolymers, state the types and proportions of each monomer unit to determine whether it is classified under 3906.10. Brand or Model: Fill in the manufacturer's brand or product model to facilitate customs identification and statistics. Use: Explain the final use of PMMA in primary forms, such as for injection molding, extrusion, coatings, etc. Packaging Specifications: State the packaging form (such as bags or drums) and net weight, which affects tariff assessment. Whether Modified: State whether it has undergone chemical modification or physical blending, such as impact-modified PMMA. Product Name: Polymethyl methacrylate (PMMA) Appearance: Transparent granules Composition and Content: PMMA >=99%, additives <=1% Monomer Unit: Methyl methacrylate homopolymer Brand: XX brand Model: XX-100 Use: Used for injection molding optical lenses Packaging Specifications: 25kg/bag, net weight 1000kg Whether Modified: Unmodified Mistakenly classifying PMMA copolymers (such as MMA-styrene copolymers) under 3906.10 when they should actually be classified under 3906.90. Mistakenly classifying PMMA already made into semi-finished products such as plates, sheets, or film under 3906.10 when it should actually be classified under 3916 or 3920. Failing to state the monomer unit ratio at the time of declaration, resulting in customs being unable to determine whether it is a homopolymer.

The core basis for classification is: 1) whether the goods are in primary form (unprocessed or only primarily processed); 2) whether the polymer is a polymethyl methacrylate homopolymer; 3) if it is a copolymer, whether the methyl methacrylate monomer unit constitutes the main component. According to the HS notes, 3906.10 applies only to polymethyl methacrylate, including its chemically modified products, but if it is copolymerized with other monomers and the MMA unit does not predominate, it is classified under 3906.90. At the same time, attention must be paid to the distinction from other headings in Chapter 39, such as polyethylene (3901), polystyrene (3903), etc. 390690 Other acrylic polymers in primary forms: 390690 covers other acrylic polymers besides PMMA, such as polyacrylic acid and acrylic copolymers. If PMMA is a copolymer and the MMA unit does not predominate, it is classified under 390690. 391610 Monofilament of acrylic polymers in primary forms (cross-sectional diameter >1 mm): 391610 is monofilament with a cross-sectional diameter >1 mm, belonging to semi-finished products; while 390610 is primary form, such as granules and powder. 392051 Plates, sheets, film, foil and strip of polymethyl methacrylate (non-cellular): 392051 refers to semi-finished or finished products already processed into plates, sheets, etc., while 390610 is primary form that has not been shaped or processed. 390320 Styrene-acrylonitrile copolymers in primary forms: 390320 is styrene-acrylonitrile copolymer, which differs chemically from PMMA, but may appear similar and must be distinguished by composition analysis. 390130 Ethylene-vinyl acetate copolymers in primary forms: 390130 is EVA, which is different from PMMA, but if declared as 'transparent granules,' care must be taken to distinguish them. Are the goods in primary form (granules, powder, liquid, etc.)? Is the polymer a polymethyl methacrylate homopolymer? If it is a copolymer, does the MMA monomer unit predominate? Does it contain additives, and do they affect classification? Has it already been processed into semi-finished products such as plates, sheets, or film?

How can I check the import tariff rate for 390610? You can check the most-favored-nation rate, general rate, value-added tax rate, and consumption tax by entering HS code 390610 on the official website of the General Administration of Customs, China International Trade Single Window, or third-party query platforms. Note that tariff rates may be adjusted with policy changes, and the latest published rates should prevail. What is the difference in HS codes between PMMA pellets and PMMA sheets? PMMA pellets are in primary form and are classified under 390610; PMMA sheets have already been processed and shaped and are classified under 392051. Classification should be judged according to the degree of processing; primary form refers to forms that have not undergone further processing, such as pellets and powder. If PMMA contains pigments, does it affect classification? Usually it does not, as long as the pigments are only additives and PMMA remains the essential component, it is still classified under 390610. However, if the pigment content is too high, it may change the characteristics of the goods and requires specific analysis. How do you determine whether a copolymer is classified under 390610? It depends on whether the methyl methacrylate monomer unit in the copolymer constitutes the main component (usually the greatest proportion by weight). If the MMA unit predominates, it is classified under 390610; otherwise, it is classified under 390690. What are the differences in declaration elements between 390610 and 390690? For 390610, the key declaration is the type and proportion of monomer units to prove it is a PMMA homopolymer; for 390690, the specific polymer type must be declared, such as polyacrylic acid or acrylic copolymers. Both require declaration of appearance, composition and content, use, etc. For cross-border e-commerce sales of PMMA products, how should the HS code be determined? It should be determined according to the form and use of the product. If it is primary-form pellets, it is classified under 390610; if it is a finished product such as acrylic sheets or lenses, it is classified under 3920 or 3926, etc. It is recommended to consult a professional customs broker or use a customs classification advance ruling. Under which code should PMMA waste and scrap be classified? PMMA waste and scrap are classified under 3915, not 390610. 3915 covers plastic waste and scrap and parings, and attention must be paid to the distinction from primary forms. How can PMMA and polycarbonate (PC) be distinguished at the time of declaration? The two may appear similar, but their chemical structures are different. PMMA is an acrylic polymer and is classified under 390610; PC is polycarbonate and is classified under 390740. They must be distinguished through composition analysis or by providing supporting documents such as MSDS.