Systematic nomenclature, polymer compounds

Union of Pure and Applied Chemists (IUPAC) has developed systematic nomenclature rules for polymers. As is the case with many small-molecule organic compounds, the IUPAC names are often complex and cumbersome. Therefore, polymer scientists often use common or abbreviated names, sometimes even product names. Poly[l- methoxycarbonyl)-l-methylethylene] (IUPAC) is almost always referred to as poly(methyl methacrylate), or PMMA, or even Lucite. IUPAC discourages the use of trademarked names, however unless it is importanfto refer to a specific commercial product. The IUPAC Macromolecular Nomenclature Commission recognizes a number of trivial names for common polymers (Metanomski 1999). 

Phosphorous is a five-valent element, and its natural oxide is P2O5, phosphorous pentoxide. It is a highly hygroscopic powder and readily reacts with water to form phosphoric acid (H3PO4). This acid when reacted with various aUcaline compounds forms phosphates. These and other modified compounds are linear or chain, cyclic or ring, and branch chain polymers. Because these compounds are polymeric, phosphates can provide a continuous structure and, hence, form good ceramics. The reader is referred to Topics in Phosphorus Chemistry by Westman [1] for details. Because of the variety of polymeric compounds formed by phosphorous, a systematic nomenclature is used in phosphate chemistry. 

Polymer compounds can be named according to the systematic nomenclature or the traditional nomenclature. 

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]. 

Other names are retained for referring to unsubstituted compounds only. Compounds derived from them by substitution must be named systematically. The names are retained because of their wide use in biochemical and in polymer nomenclature. A few examples are given here. 

A systematic lUPAC nomenclature exists for polymers just as it docs for organic and inorganic chemicals. This polymer nomenclature is rarely used, however, because a trivial naming system is deeply entrenched through the force of usage. A similar situation prevails with all chemical species which are commercially important commodities. Thus, large-scale users of the compound 1-40... 

Organic polymers have traditionally been named on the basis of the monomer used, a hypothetical monomer, or a semi-systematic structure. Alternatively, they may be named in the same way as organic compounds, i.e., on the basis of a structure as drawn. The former method, often called source-based nomenclature or monomer-based nomenclature , sometimes results in ambiguity and multiple names for a single material. The latter method, termed structure-based nomenclature , generates a sometimes cumbersome unique name for a given polymer, independent of its source. Within their limitations, both types of names are acceptable and weU-documented. The use of stereochemical descriptors with both types of polymer nomenclature has been published. ... 

Polymer molecules which differ only in length, end-groups, or in the frequency of sone occasional structural irregularity such as branching, but which are composed predominantly of identical repeating units, are ordinarily considered to be the same compound. Hence it is only necessary to name the repeating unit. Systematic names for the diradicals which comprise the repeating units in polymers are awkward and unfamiliar to most chemists. This type of nomenclature was proposed by the... 

Having reduced the problem of polymer nomenclature to one of source nomenclature, it is now necessary to choose one of the established systems of naming organic compounds. Chemical Abstracts has long set the standard for systematic chemical nomenclature for indexing purposes, which at the same time conforms to accepted... 

The need for a systematic method of storage and retrieval of information on such a large number of compounds is obvious, but the absence of a widely accepted syston of nomenclature for polymers is a serious impediment to the use of an alphabetical index. I am pleased to acknowledge my indebtedness to Mrs. CHRISTEL KAPPES WASSON for invaluable assistance in developing the system, described herein, which makes alphabetizing practical, and to Miss BARBARA ALLSTROM for help with problems of naming and indexing. 

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