
242 HIGH PERFORMANCE POLYMERS
C
C
NHHN
NHHNH
2
NNH
2
1,4-Benzenedicarboximidic acid dihydrazide
O
COOH
HOOC
4′4′-diphenylether dicarboxylic acid
Ar =
2,2′-(oxydi-4,1-phenylene)bis[5-(4-fluorophenyl)-1,3,4-oxadiazole]
NN
O
ArOrAAr Ar
O
NN
FF
1,4-Phenylene-5,5´-tetrazole
N
N
N
NN
N
N
N
CC
OO
Cl
Cl
Isophthaloyl chloride
Figure 10.1 Monomers used for PODA.
SS
FF
FF
NN
O
OO
CCOO
S
Br
F
F
F
Cl
+
S
COOH
F
F
BuLi, CO
2
S
C
Cl
O
F
F
S
C
Cl
O
F
F
N
N
H
H
H
H
Figure 10.2 Synthesis of a crosslinkable oxadiazole
monomer [20].
10.2 Polymerization and
Fabrication
PODAs can be synthesized, either by [4]:
• Forming the oxadiazole moiety in the course of
synthesis of the polymer, mostly via a precursor
polymer, or
• Condensing monomers