GRAPHIC REPRESENTATIONS (CHEMICAL FORMULAS) OF MACROMOLECULES - (IUPAC RECOMMENDATIONS 1994)

The unambiguous graphic representation of molecules is specially impor tant for macromolecules, which often exhibit a larger number of struct ural features than do molecules of low molecular weight. For example, the formula of a copolymer should immediately imply if it is meant to present a block copolymer or a copolymer with an unspecified sequence of monomeric units. Thus, a two-block copolymer consisting of a block containing p monomeric units A and a block comprising q monomeric unit s B is represented by the formula (A)(p)-(B)(q) whereas the correspond ing random copolymer is represented by the formula (-A-/-B-)(n) where p + q = n. Overall, the document provides rules and examples for the g raphic representation of constitutional repeating units and monomeric units, regular and irregular polymers of simple as well as complex str uctures, including organic and inorganic homopolymers, alternating and periodic copolymers, statistical, random and unspecified copolymers, block copolymers and graft copolymers, including star polymers. The pr oposed graphic representations of chemical formulae for polymers are s uitable for presentation through graphics computer programs.