1. Within any one heading of this chapter, polymers (including copolymers) and chemically modified polymers are to be classified according to the following provisions:

(a) Where there is a sub-heading named “other” in the same series:

(1) The designation in a sub-heading of a polymer by the prefix "poly” (for example, polyethylene and polyamide –6, 6) means that the constituent monomer unit or monomer units of the named polymer taken together must contribute 95% or more by weight of the total polymer content;
(2) The copolymers named in subheadings 3901 30, 3903 20, 3903 30 and 3904 30 are to be classified in those subheadings, provided that the co monomer units of the named copolymers contribute 95% or more by weight of the total polymer content.

(3) Chemically modified polymer are to be classified in the subheading named “other”, provided that the chemically modified polymers are not more specifically covered by an other subheading.

(4) Polymers not meeting (1), (2) or (3) above are to be classified in the sub heading, among the remaining subheadings in the series, covering polymers of that monomer unit which predominates by weight over every other single co monomer unit. For this purpose, constituent monomer units of polymers falling in the same subheading shall be taken together. Only the constituent co monomer units of the polymers in the series of subheadings under consideration are to be compared;

(b) Where there is no subheading named “other“ in the same series:

(1) Polymers are to be classified in the subheading covering polymers of that monomer unit which predominates by weight over every other single co monomer unit. For this purpose, constituent monomer units of polymers falling in the same subheading shall be taken together. Only the constituent co monomer units of the polymers in the series under consideration are to be compared.

(2) Chemically modified polymers are to be classified in the subheading appropriate to the unmodified polymer.

Polymer blends are to be classified in the same sub-heading as polymers of the same monomer units in the same proportions.

2. For the purposes of sub-heading 3920 43, the term “plasticisers” includes secondary plasticisers.