Page 25 - Carrahers_Polymer_Chemistry,_Eighth_Edition

xxiv Polymer Nomenclature

R
H C
2
R n

Styrene Polystyrene

The vast majority of commercial polymers based on the vinyl group (H C=CHX) or the vinyli-
2
dene group (H C=CX ) as the repeat unit are known by their source-based names. Thus, polyethyl-
2
2
ene is the name of the polymer synthesized from the monomer ethylene; poly(vinyl chloride) from
the monomer vinyl chloride, and poly(methyl methacrylate) from methyl methacrylate.
Many condensation polymers are also named in this manner. In the case of poly(ethylene tere-
phthalate), the glycol portion of the name of the monomer, ethylene glycol, is used in constructing
the polymer name, so that the name is actually a hybrid of a source-based and a structure-based
name.

R
O
OH HO O
O O

HO O OH
O n R

Poly(ethylene terephthalate)

This polymer is well known by a number of trade names, such as Dacron, its common grouping,
polyester, and by an abbreviation PET or PETE.
Although it is often suggested that parentheses be used in naming polymers of more than one word
[like poly(vinyl chloride)], but not for single word-polymers (like polyethylene), some authors entirely
omit the use of parentheses for either case (like polyvinyl chloride) so even here there exists a variety
of practices. We will employ the use of parentheses for naming polymers of more than one word.
Copolymers are composed of two or more monomers. Source-based names are conveniently
employed to describe copolymers using an appropriate term between the names of the monomers.
Any of the half dozen or so connecting terms may be used depending on what is known about the
structure of the copolymer. When no information is known or intended to be conveyed the connec-
tive term “co” is employed in the general format poly(A-co-B), where A and B are the names of
the two monomers. An unspecified copolymer of styrene and methyl methacrylate would be called

poly[styrene-co(methyl methacrylate)].
Kraton, the yellow rubber-like material often found on the bottom of running shoes, is a copol-
ymer whose structural information is known. It is formed from a group of styrene units, that is, a
“block” of polystyrene attached to a group of butadiene units, or a block of polybutadiene, which is
attached to another block of polystyrene forming a triblock copolymer. The general representation
of such a block might be –AAAAAAAABBBBBBBAAAAAAAA–, where each A and B repre-
sents an individual monomer unit. The proper source-based name for Kraton is polystyrene-block-
polybutadiene-block-polystyrene, or poly-block-styrene-block-polybutadiene-block-polystyrene with

the prefix “poly” being retained for each block. Again, some authors will omit the “poly” use, giving
polystyrene-block-butadiene-block-styrene.

9/14/2010 3:35:45 PM
K10478.indb xxiv 9/14/2010 3:35:45 PM
K10478.indb xxiv