Number: 2003-042-1-800
Title: Source-based nomenclature
of single-strand organic polymers
Task Group
Chairman: Tatsuki
Kitayama
Members: David
Haddleton, Michael
Hess, Philip Hodge,
Kaz Horie, Aubrey
Jenkins, Jaroslav
Kahovec, Pavel
Kratochvil, Itaru
Mita, Werner Mormann,
Christopher K. Ober,
Stanislaw Penczek,
Robert F. T. Stepto,
Kevin Thurlow,
Jiri Vohlidal,
and Edward S. Wilks
Objective:
To provide systematic and practical recommendations for source-based
nomenclature of single-strand organic polymers.
Description:
NECESSITY OF A NEW DOCUMENT
When the structure-based nomenclature of polymers was first published
(1976), the commission of macromolecular nomenclature expected that
the system would be soon widely used. But this was not the case
and the source-based names, of which only ca.20 were allowed as
exceptions in the Appendix of the document, still prevail over structure-based.
Though the structure-based nomenclature is very systematic and
logical so as to give only one name for one polymer, it often results
in very complex or very long names contrary to the economics of
expression (short, easy to understand, easy to memorize, etc). This
is one of the reasons why structure-based names are not so popular.
Another reason for the preference for source-based names is their
direct relation to monomer names and to the historical trivial names.
Even the commission itself decided to use source-based names in
the Copolymer document (1985) because of their simplicity and practicality.
But no clear definitions or rules for the basic concepts of source-based
nomenclature were given there. Very recently the commission officially
admitted for the first time the general use of the source-based
nomenclature for homopolymers in the "Generic" document
(2001) saying that "The commission has now decided to recommend
source-based nomenclature as an alternative official nomenclature
for homopolymers".
However, because the source-based nomenclature has been treated
as a second ranked nomenclature for a long time, no scrutiny has
been made on it and many problems have been left unsolved, e.g.,
there are many cases in which one polymer has two or more names
without any seniority rules or one name corresponds to several different
polymers. It is desirable to minimize such shortcomings while keeping
the practicality of the source-based nomenclature.
ISSUES TO BE RECONSIDERED
Among many issues to be reconsidered, some examples are briefly
shown in the following.
1) Issues relevant to both homopolymers and copolymers
1-1 Establish the rules for choosing the name(s) of a monomer from
two or three different names, i.e., (1) IUPAC systematic name (e.g.,
ethene, vinylbenzene, oxirane, etc.), (2) IUPAC approved trivial
names (e.g., styrene) and (3) trivial names not approved by IUPAC
(e.g., ethylene, ethylene oxide,).
1-2 Select one preferred name among plural names all conforming
to the rules to have only one preferred name for one polymer as
far as possible.
1-3 Expand the definition of the source-based name to be able to
cover PET (polyethylene terephthalate) type names (See 3-2).
2) Issues relevant only to homopolymers
Find better generic names for the isomeric regular homopolymers
and irregular homopolymers such as polyisoprenes, for which the
generic convention allows to distinguish isomeric plural homopolymers,
e.g., polyalkylene:isoprene and polyalkenylene;isoprene. Use of
simpler class names, such as poly(1,2-adduct):isoprene, poly (cis-1,4-adduct):isoprene,
have to be discussed.
3) Issues relevant only to copolymers
3-1 Discard the "alternative nomenclature"given in the
Appendix of the current Copolymer document, to avoid having two
nomenclature systems.
3-2 Avoid many names for a copolymer prepared by polycondensation,
in which a same regular copolymer can be prepared from different
monomers ,e.g. monomer A) ethylene glycol, ethylene oxide, etc.
and monomer B) terephthalic acid or various acid derivatives.
STRUCTURE OF THE NEW DOCUMENT
Due to the tight correlations among nomenclature of homopolymers,
that of copolymers, and the generic nomenclature, it is desirable
to have all of them in one document. Most part of the current "Copolymer
document" (1985) and the "Generic document" (2001)
will be incorporated in the new document probably by modifying them
in more concise form, eventually superseding them. The document
"Source-based nomenclature of nonlinear macromolecules and
macromolecular assemblies" is of different nature and should
not be included in this document.
Contents
1. Introduction (Reasons for revision / Scope)
2. General (Definitions / Generic Convention / Preferred names)
3. Names of Monomers (Allowed trivial/Systematic/ Hypothetical)
4. Homopolymers (Basic rules/ Use of generic names)
5. Copolymers (co, stat, ran, alt, per / block,graft/ PET type names/
Use of generic convention for complicated copolymers)
Progress:
Last update: 17 April 2007