Poly nomenclature

Wilks, E. S. Macromolecular Nomenclature Note No. 17 Whither Nomenclature Polym. Prepr. 40(2), 6-11 (1999) also available at www.chem.umr.edu/ poly/nomenclature.html. 

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). 

Examples of the two macromolecular nomenclature systems are as foUows. For source-based names for homopolymers and copolymers polyacrylonitrile, poly(methyl methacrylate), poly(acrylainide- (9-vinylpyrroHdinone), polybutadiene- /oi / -polystyrene, and poly(propyl... 

Because the rules for organic nomenclature determine the priority of naming different carbon chains from their relative lengths, the systematic names for type AABB polyamides depend on the relative length of the carbon chains between the amide nitrogens and the two carbonyl functions of the polymer for aUphatic nylon-Ayy, when x < the lUPAC name is poly[imino-R imino(l2y-dioxo-R )]. When x > then the name is... 

Polyaza six-membered ring systems, 3, 1039-1086 Poly-e-caprolactone production, 7, 589 Polycyclic compounds nomenclature, 1, 14-28 Polyfuroxans, 6, 426 Polygermacyclopentanes, 1, 609... 

Mention should be made of the nomenclature for the polymer. Industrially the materially is invariably known in the English-speaking world as polypropylene. However, the lUPAC name for the monomer is propene and until 1975 the recommended lUPAC name was polypropene, a term very rarely used. The latest lUPAC rules base the name of a polymer on the constitutional repeating unit, which in this case is a propylene unit (c.f. a methylene unit for polyethylene) and this leads to the name poly(propylene) (i.e. with brackets). In this volume the more common, unbracketed but still unambiguous name will be used. 

In the standard nomenclature [poly(MA)-gra/r-poly(MR)] the first named monomer(s) form the backbone while those named second are the grafts or arms. Thus, PMMA-gra//-PS indicates a backbone of PMMA and grafts of PS. 

This polymer has one of the simplest molecular structures ([CH2CH2— ] ) and is at present the largest toimage plastic material, having first been produced commercially in 1939 for use in electrical insulation. There is a difficulty over the nomenclature of this polymer. The lUPAC recommended name for the monomer is ethene, rather than the older ethylene. Hence the lUPAC name for the polymer is poly (ethene). However, this name is almost never used by chemists working with the material throughout this book, therefore, this polymer will be referred to by its more widespread name, poly(ethylene). 

Like poly(ethylene), there are formal problems with the nomenclature of this polymer, since its lUPAC name, poly(propene), is also rarely if ever used hy polymer chemists. Since, in practice, no ambiguity is associated with the non-systematic name, this is the one that is generally used, as it will he throughout this hook. 

Correct IUPAC nomenclature poly(oxy-2,6-dimethyl-l,4-pheylene), PPO, poly(oxy-l,4-phenylenesulfonyl-l, 4 -phenyleneoxy-l",4 phenylene (1 -methylethylidene)-l , 4" -phenylene), poly(arylene ether sulfone), and poly(oxy-(2-hydroxytrimethylene) oxy-l,4-phenylene(l -methylethylidene)-l, 4 -phenylene), phenoxy resin. 

PTT is made by the melt polycondensation of PDO with either terephthalic acid or dimethyl terephthalate. The chemical structure is shown in Figure 11.1. It is also called 3GT in the polyester industry, with G and T standing for glycol and terephthalate, respectively. The number preceding G stands for the number of methylene units in the glycol moiety. In the literature, polypropylene terephthalate) (PPT) is also frequently encountered however, this nomenclature does not distinguish whether the glycol moiety is made from a branched 1,2-propanediol or a linear 1,3-propanediol. Another abbreviation sometimes used in the literature is PTMT, which could be confused with poly(tetramethylene terephthalate),... 

Fig. 6. Post-translational modifications of core and linker histones. The sites of acetylation, phosphorylation, poly-ADP ribosylation, methylation, and ubiquitination are incficated by numbers that correspond to the amino acid position from the N-termini of the molecules. The nomenclature of histone HI variants is as in Fig. 3. The length of C- and N-terminal tails is in relative scale between core histones to illustrate primary structural differences between these proteins.

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]. 

---