Polymers nomenclature searching

Source-based polymer representation (also called product-by-process representation ) the polymer is represented in terms of the names (see Nomenclature Searching) and structures (where known) of the substance(s) from which the polymer was formed. For example, polyethylene is represented by the expression (CH2=CH2)x, because the structure of the monomer, ethylene, from which it is made is CH2=CH2. 

Chemical Abstracts Service Information System Nomenclature Searching Nomenclature Automatic Generation and Conversion Normal Modes Polymer Brushes Structure and Substructure Searching Structure Databases Structure Representation. 

Thus polymer structures represented on paper or stored in a database as ideal or theoretical representations are frequently not true representations of actual polymer structures. Before September 2002 all these problems and questions posed significant difficulties for the average polymer searcher. The following sections discuss what has been achieved to date in terms of organizing polymer structures and nomenclature, and of facilitating polymer searching. 

Classification of polymers by functional type is not generally suitable because some of the classes would be excessively large and the reader might have to search several classes to find a particular compound. Indexing by formula requires too much time and effort in searching for common polymers. The best solution is a simple alphabetical listing. To make an alphabetical listing practical it is necessary to define a set of rules of nomenclature. 

Because in most cases no clear lUPAC nomenclature exists for metal-containing macromolecules or macromolecular metal complexes, it is not possible to obtain by a Chemical Abstract literature search a detailed information on them. One has to look for each individual metal, metal ion, metal complex, metal chelate, ligand or also polymer. For type I usually rational nomenclature is used (for example cobalt(II) complex with/ of poly(4-vinylpyridine) or 2,9,16,23-tetrakis(4-hydroxyphenyl)phthalocyanine zinc(II)... 

An important function of nomenclature is for the storage and retrieval of information. It is therefore of interest to examine, with the help of this example, the practice of Chemical Abstracts— the prime chemical search tool of the Western world—which, except for a small number of macromolecular materials of well-defined structure, indexes polymers on the basis of their supposed monomers or precursors rather than as substances in their own right. Until 1971," the substances in question were indexed under terephthalic acid, polyester with 1,4-butanediol and polytetramethylene glycol . Subsequently, partial use has been made of lUPAC-recommended structure-based nomenclature, leading to a cycle of expressions of the type 1,4-benzenedicarboxylic acid, polymer with 1,4-butanediol and a-hydro-cu-hydroxypoly(oxy-l,4-butanediyl) , permuted to commence with each reactant in turn. It will be noted that these terms presuppose what is not the case in practice, that terephthalic acid (1,4-benzenedicarboxylic acid) is an immediate precursor of the polymers. However, further search will show the polymers located under a cycle of names of the type poly(oxy-1,4-butanediyl), a-hydro-m-hydroxy, polymer with 1,4-butanediol and dimethyl 1,4-benzenedicar-boxylate , and will reveal that the assigned Chemical Abstracts Registry numbers, which are intended... 

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