High Performance Polymers, 2nd Edition

222 HIGH PERFORMANCE POLYMERS

HO C

O

OOH

HO C

O

NHNH

2

+

HO C

O

NH NH C

O

OH

NH

3

Cl

NN

N

OHHO

Figure 9.2 Synthesis of Di(hydroxyphenyl)-1,2,4-

triazole monomers [2].

compounds. The reactions are carried out in polar

aprotic solvents, such as sulfolane or diphenyl sulfone,

using alkali metal bases, such as potassium carbonate,

at elevated temperatures under nitrogen.

The di(hydroxyphenyl)-1,2,4-triazole monomers

are synthesized by reacting bis-(4-hydroxyphenyl)-

hydrazide with aniline hydrochloride at ca. 250

◦

C

in the melt or by reacting 1,3 or 1,4-bis-(4-

hydroxyphenyl)-phenylene dihydrazide with 2 mol

of aniline hydrochloride in the melt. The syn-

thesis is shown in Figure ...