Macromolecules nomenclature

IUPAC Commission on Macromolecules Nomenclature, Pure Appl. Chem. 1979, 51, 1101 1981, 53, 733. 

The nomenclature of macromolecules can be compHcated when there is Httle or no regularity in the molecules for such molecules, the stmctural details may also be uncertain. In cases where the macromolecule is a polymeric chain with some uncertainties about regularity in its stmcture, a simple expedient is to name the polymer after the monomer that gave rise to it. Thus there are source-based names such as poly(vinyl chloride). 

The first attempt to formulate a systematic nomenclature for polymers was based on the smallest repeating stmctural unit it was pubHshed in 1952 by a Subcommission on Nomenclature of the lUPAC Commission on Macromolecules (95). The report covered not only the naming of polymers, but also symbology and definitions of terms. However, these nomenclature recommendations did not receive widespread acceptance. Further progress was slow, with a report on steric regularity in high polymers pubHshed in 1962 and updated in 1966 (96). 

The IUPAC Commission on Macromolecular Nomenclature recommended micronetwork as a term for microgel [47] and defined it as a highly ramified macromolecule of colloidal dimensions. However, it should be noted that a micronetwork implies a structure and not a macromolecule or a particle, that a high ramification is not typical for these molecular particles and that the same wrong dimension is used as with microgel. 

M. L. Huggins, G. Natta, V. Desreux, H. Mark (for lUPAC Commission on Macromolecules). Report on nomenclature dealing with steric regularity in high polymers ,/. Polym. Sci. 56, 153-161 (1962) Pure Appl. Chem. 12, 643-656 (1966). 

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.. ... 

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. 

Structure-based nomenclature is based on a method of naming the sequence of constitutional or structural units that represent the repeating pattern of the structure of a typical macromolecule in a polymer. The name bears no direct relation to the structure of the (co)monomer(s) used to synthesize the polymer. 

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. 

American Chemical Society. A structure-based nomenclature for linear polymers , Macromolecules 1, 193-198 (1968). 

Graphic representations (chemical formulae) of macromolecules are used extensively in the scientific literature on polymers including lUPAC documents on macromolecular nomenclature. This document establishes rules for the unambiguous representation of macromolecules by chemical formulae. The rules apply principally to synthetic macromolecules. Insofar as is possible, these rules are consistent with the formulae given in lUPAC documents [2-4] and they also cover the presentation of formulae for irregular macromolecules [5], copolymer molecules [1, 6] and star macromolecules. 

As a general rule, chemical formulae for macromolecules should be written only in those cases where the structures of the constitutional units are known. A given structure may, however, be written in various ways to emphasize specific structural features such alternative structures need not necessarily reflect the order of citation dictated by structure-based nomenclature [2]. 

The first publication of the lUPAC in the area of macromolecular nomenclature was in 1952 by the Sub-commission on Nomenclature of the then lUPAC Commission on Macromolecules, which drew on the talents of such remarkable individuals as J. J. Hermans, M. L. Huggins, O. Kratky, and H. F. Mark. That report [1] was a landmark in that, for the first time, it systematized the naming of macromolecules and certain symbols and terms commonly used in polymer science. It introduced the use of parentheses in source-based polymer names when the monomer from which the polymer is derived consists of more than one word, a practice that is now widely followed, and it recommended an entirely new way of naming polymers based on their structure that included the suffix amer , a recommendation that has been almost totally ignored. After ten years, the Sub-commission issued its second report [2], which dealt with the then-burgeoning field of stereoregular polymers. A revision [3] of definitions in the original report appeared four years later. In 1968, a summary report [4] of the activities of the Subcommission was published. 

Report of the Committee on Nomenclature of the International Commission on Macromolecules, J. Polym. Sci., PartB Polym. Lett. 6, 257-260 (1968). Obsolete. 

Source-based nomenclature for non-linear macromolecules and macromolecular assemblies (lUPAC Recommendations 1997), PureAppl. Chem. 69, 2511-2521 (1997). Reprinted as Chapter 20, this edition. 

By copolymerization we understand the mutual polymerization of two or more monomers, with the resulting macromolecules containing repeating units of all the participating monomers. Depending on the distribution of the monomers in the macromolecules one differentiates four types of copolymers (nomenclature of copolymers see Sect.1.2) ... 

Polymeric compounds (macromolecules) do not fall easily into either of these categories, and for them a subsystem of macromolecular nomenclature has been developed. A brief introduction to macromolecular nomenclature is presented in Chapter 6. Non-stoichiometric compounds also are clearly difficult to name within the constraints of a description which generally implies localised electron-pair bonds or specific atom-atom interactions. For these, further systems of nomenclature are in the process of development. Finally, oxoacids and inorganic rings and chains have their own nomenclature variants. 

The Commission on Macromolecular Nomenclature is currently working on the extension of macromolecular nomenclature to branched and cyclic macromolecules, micronetworks and polymer networks, and to assemblies held together by non-covalent bonds or forces, such as polymer blends, interpenetrating networks and polymer complexes. 

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