Chemistry Reference
In-Depth Information
A Japanese patent [
211
] describes preparation of isophthalic type polyesters that
include
monomers with pendant
azo
groups:
O
O
X
X
N
OO
N
n
where Y is a hydrogen or a lower alkyl group;
2-18. Polyesters based on this
monomers are claimed to be useful for optical recording media such as holograms recording with
low light absorption or without loss and wide range of working wavelengths.
Izumi and coworkers carried out similar preparations of conjugated polymers with azobenzenes in
the main chain [
212
,
213
]. Application of various palladium-catalyzed coupling methods such as the
Suzuki coupling and the Heck reactions allowed formation of poly(
m ¼
1-3;
n ¼
p
-phenylene)- and poly(phenyl
vinylene)-based polymers:
R"
R"
N
N
n
R"
R"
R"
R"
N
N
n
R"
R"
R"
R"
R'
N
N
R"
R"
n
R'
where R
0
,R
00
¼
-C
6
H
13
.
These isomerization processes are also accompanied by changes in the three-dimensional hydro-
dynamic volumes of the polymers [
213
].
Hor
n
