3901 - Polymers of ethylene, in primary forms:

This HTS category, 3901, encompasses various forms of polymers derived from ethylene, provided they are in their primary physical forms. These primary forms typically include granules, powders, lumps, and blocks, which are the raw materials used in subsequent manufacturing processes. This classification is crucial for identifying the foundational plastic materials before they are molded or shaped into finished goods.

Distinguishing this category from its siblings is essential. While other HTS chapters at this high level might cover live animals, minerals, or other basic commodities, Chapter 39 is specifically dedicated to plastics and articles thereof. Within Chapter 39, 3901 stands out as the starting point for identifying ethylene-based polymers, differentiating them from polymers of other chemical bases.

The subcategories within 3901 provide further specificity based on key physical and chemical characteristics of these ethylene polymers. For instance, subdivisions are made based on specific gravity, which relates to density and can influence the polymer's properties and applications. Further distinctions are made for copolymers, such as ethylene-vinyl acetate, highlighting the combination of ethylene with other monomers to achieve tailored material properties. The existence of these subcategories allows for precise classification based on technical specifications that are critical for import and export.