
16: POLY(BENZIMIDAZOLE)S 375
Table 16.3 Properties of a PBI
a
[20]
Property Value Unit
Density 1.30 gcm
−3
Tensile modulus 5860 MPa
Flexural strength 221 MPa
Compressive modulus 5860 MPa
Glass transition temperature 427
◦
C
Ther mal conductivity 0.40 Wm
−1
K
−1
Volume resistivity 2 × 10
15
cm
Dielectric strength 23 kV mm
−1
Limiting oxygen index 58 %
a
Celazole
TM
U-60 PBI, PBI Performance Products, Inc.
sulfonation is carried out by dissolving the polymer in
a large excess of sulfuric acid.
16.3 Properties
PBI polymers are hydrophobic in nature [16]. For
this reason, PBI powders or shaped articles cannot be
wet with a hydrophilic solvent. The hydrophobic char-
acter of