Source-based nomenclature

The name of the polymer is formed by attaching the prefix poly to the name of the real or assumed monomer, or the starting material (source) from which the polymer is derived. 

Parentheses are used when the name of the monomer consists of two or more words. 

For copolymers, a connective (infix) is inserted, which depends on what is known about the arrangement of the constitutional units. 

poly[styrene-co-(methyl methacrylate)] or copoly(styrene/methyl methacrylate) (an unknown or unspecified arrangement) 

poly(styrene-5tot-acrylonitrile-5to -butadiene) or 5to -copoly(styrene/-acrylonitrile/butadiene) (a statistical arrangement, obeying known statistical laws) 

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A Macromolecular Division of lUPAC was created in 1967, and it created a permanent Commission on Macromolecular Nomenclature, parallel to the other nomenclature commissions. The Commission over the years has issued recommendations on basic definitions, stereochemical definitions and notations, stmcture-based nomenclature for regular single-strand organic polymers and regular single-strand and quasisingle-strand inorganic and coordination polymers, source-based nomenclature for copolymers, and abbreviations for polymers. AH of these are coUected in a compendium referred to as the lUPAC Purple Book (99). 

Generic source-based nomenclature for polymers (lUPAC Recommendations 200 ), Pure Appl. Chem. 73, 1511-1519 (2001). Errata, Pure Appl. Chem. 74, 2019 (2002). Reprinted as Chapter 21, this edition. 

Two systems of polymer nomenclature have been introduced - the source-based and the structure-based. The latter cannot be used for all types of macromolecule, e.g., statistieal copolymer molecules and polymer networks. lUPAC expresses no strong preference for the use of structure-based nomenclature versus source-based nomenclature, but for certain purposes one system of naming may be preferred to the other.. ... 

The principal deficiency of source-based nomenclature is that the chemical structure of the monomeric unit in a polymer is not identical with that of the monomer, e.g., -CHX-CH2- versus CHX=CH2. The structure of the constitutional repeating unit (CRU) may also not be clearly identified in this scheme for example, the name polyacrylaldehyde does not indicate whether (i) the vinyl group or (ii) the aldehyde group was the locus of polymerization. 

Despite these serious deficiencies, source-based nomenclature is still firmly entrenched in the scientific literature. It originated at a time when polymer science was less developed and the structures of most polymers were ill-defined. The significant advances made during the last 50 years in the structure determination of polymers are gradually shifting the emphasis of polymer nomenclature away from starting materials and toward the structure of the synthesized macromolecules. 

There are cases in which the simplicity of source-based nomenclature leads to ambiguous names for homopolymers. Two examples illustrate this point. 

Despite the Commission s long-standing position, the scientific community has continued to use source-based nomenclature for homopolymers such as polystyrene and poly(vinyl acetate) because of their simplicity, convenience and obvious relationship with the monomers from which the homopolymers are prepared. The Commission therefore decided to recommend source-based nomenclature as an alternative official nomenclature for homopolymers in a 2001 publication [2]. Consequently, both source-based and structure-based names are now available for most polymers. The names of monomers in the source-based names may be traditional or semi-systematic, if well established by usage, and not necessarily only those retained in the 1993 A Guide to lUPAC Nomenclature of Organic Compounds [3]. 

The same publication [2] recommended a generic source-based nomenclature, which comprises the optional addition of a polymer class name to the source-based name of the polymer. The addition is recommended when it is necessary to avoid ambiguity or to add clarification. 

Similarly to homopolymers, source-based nomenclature has been applied to copolymers [4]. The principal problem is to define the kind of arrangement in which various types of monomeric units are related to each other. Seven types of separate arrangements have been defined, which are shown in Table 1, where A, B and C represent the names of monomers. The monomer names are linked either through an italicized qualifier or connective (infix), such as -CO- , to form the name of the copolymer, as in poly(styrene-co-acrylonitrile). The order of citation of the monomers is arbitrary. 

Table 3. lUPAC Source-Based Nomenclature for Non-Linear Macromolecules and Macromolecular Assemblies [5]... 

In source-based nomenclature for non-linear maeromoleeules and maeromoleeular assemblies, junction units are optionally specified by their source-based names after the name of the macromolecule with the connective (Greek) v, separated by hyphens [5]. yis given a numerieal value. 

Structure-based and source-based nomenclature rules have been extended to regular double-strand (ladder and spiro) organic polymers [7]. A double-strand polymer is defined as a polymer the molecules of which are formed by an uninterrupted sequence of rings with adjacent rings having one atom in common (spiro polymer) or two or more atoms in common (ladder polymer). 

Source-based nomenclature identifies the starting monomer(s) from which the doublestrand polymer is prepared with addition of an appropriate prefix "ladder- or "spiro- . Examples are ... 

In 1985, the Commission also published rules on source-based nomenclature for copolymers [3] which by definition are polymers derived from more than one species of monomer [4]. 

The source-based nomenclature identifies the starting material(s) from which the ladder or spiro polymer is prepared. It is derived from the nomenclature system for copolymers [3]. The system is based on the following principles ... 

In principle, a comprehensive structure-based system of naming copolymers would be desirable. However, such a system presupposes a knowledge of the structural identity of all the constitutional units as well as their sequential arrangements within the polymer molecules this information is rarely available for the synthetic polymers encountered in practice. For this reason, the proposals presented in this Report embody an essentially source-based nomenclature system. 

Most trivial names, such as polystyrene, are source-based names. Hitherto, the Commission has not systematically recommended source-based names for homopolymers because it considered that the more rigorous structure-based names were more appropriate for scientific communications. However, since the publication of Nomenclature of Regular Single-Strand Organic Polymers in 1976, scientists, in both industry and academia, have continued to use trivial names. Even the Commission itself adopted (1985) a source-based nomenclature for copolymers because of its simplicity and practicality. Based on these facts, the Commission has now decided to recommend source-based... 

GENERIC SOURCE-BASED NOMENCLATURE OF POLYMERS 3.1 Fundamental Principles... 

The system presented here can be applied to almost all homopolymers, copolymers and others, such as networks. However, generic source-based nomenclature should not be considered as a third nomenclature system to be added to the other two systems of nomenclature it must be considered as an auxiliary system and a simple extension of current source-based nomenclature. When the generic part of the name is eliminated from the name of a polymer, the well-established source-based name remains. 

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