Page 31 - Carrahers_Polymer_Chemistry,_Eighth_Edition

xxx Polymer Nomenclature

O O
—
−(−NH−C−CH −C−NH−CH 2 −CH 2 −CH 2 −) n −
—
—
—
2
is named poly[imino(1, 3-dioxo-1,3-propanediyl)imino-1,3-propanediyl].
C. In otherwise identical subunits, there are three items to be considered in decreasing order
of importance:
a. Maximum substitution: thus, 2,3,5-trichloro-p-phenylene is senior to 2,5-dichloro-p-
phenylene, which in turn is senior to 2-chloro-p-phyenylene
b. Lowest locants: thus, 2,3-dichloro-p-phenylene is senior to 2,5-dichloro-p-phenylene
c. Earliest alphabetical order: thus, 2-bromo-p-phenylene is senior to 2-chloro-p-phe-
nylene, which is senior to 2-iodo-p-phenylene.
D. Where there is no conflict with other guidelines, triple bonds are senior to double bonds,

which in turn are senior to single bonds; multiple bonds should be assigned the lowest pos-
sible locants. Thus, the polymer from 1,3-butanediene polymerized in the so-called “1,4-”
mode is usually drawn as –(–C–C=C–C–)– but it is named as drawn as –(–C=C–C–C–)–
and named poly(1-butene-1,4-diyl) with the appropriate “cis-” or “trans-” designation.
Polyisoprene, typically drawn as

–(–CH –C(CH )=CH–CH –) –
2 3 2 n
is frequently named poly(2-methyl-1,3-butadiene) but it is named as though its structure is

–(C(CH )=CH–CH –CH –) –
3 2 2 n
with the name poly(1-methyl-1-butene-1,4-diyl).
Substituents are named as one of several classes. The most important ones are dealt with
here. For monoatomic radicals from borane, methane, silane (and other Group IVA elements)
they are named by replacing the “ane” ending by “yl,” “ylene,” and “ylidyne” to denote the
loss of one, two, or three hydrogen atoms, respectively.

H B– boryl H C– methyl H C= methylene HC≡ methylidyne
2 3 2

Acyclic hydrocarbon radicals are named from the skeletons by replacing “ane,” “ene,” and
“yne” suffixes by “yl,” “enyl,” and “ynyl,” respectively.

CH –CH – ethyl CH –CH –CH – propyl –CH –CH – 1,2-ethanediyl
3 2 3 2 2 2 2
–CH=CH– 1,2-ethenediyl H C=CH–CH= 2-propenylidene
2
|| |
−CH −C-CH −1,3-propanediyl-2-ylidene −CH −CH−CH −1,2,3-propanetriyl
2 2 2 2
Table 4 contains the names of selected bivalent radicals that may be of use to polymer chemists.

SEARCHING
Searching is made much simpler with computer systems such as SciFinder Scholar, where the name
or CA# can be entered and references related to that compound are forthcoming. Teasing out the

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