temperature from 93 to 473 K), non-combustible, non-fusible, charred at 693 K,
sufficiently resistant to chemicals (acids, alkalis, organic solvents), have a low water
absorption - up to 1,5-2% at 68 % relative humidity. Twaron aramid fiber (Enka
enterprise, Germany, Tekhnora (NM-50) Teijin company, Japan, Terlon fibers, SVM
(VNIIVLON), Armos (Russia) are the analogs of Kevlar. Aramid fibers of such type
as Nomex III and Kermel (Ren-Poulins Company, France) are distinguished by high
heat resistance and chemical resistance. The properties of fibers are given in tab. 2.
Table 2 The main properties of fibers with high resistance to thermal
and chemical influences
F
ibe
rs
D
ens
it
y, g/
cm
3
M
odul
us
of
te
ns
il
e
el
as
ti
ci
ty, G
P
a
S
tre
ngt
h,
cH
/
T
ex
E
longa
ti
on, %
Maintaining of
durability, %
E
qui
li
br
ium
hum
idi
ty
(n.c
.), %
at
573 К
at 573 К
during
100 hours
Aramid (phenylone,
Nomex, Koneks, Apail)
1.37-1.38
8-20
40-50
15-20
40-50
60-70
4-5
Polyamidoimide
(Kermel)
1.34-1.35
5-9
35-60
10-23
–
–
2-3.5
Polyimide
(Arimid, Kapton, R-84)
1.41-1.43
9-15
40-60
6-12
55-65
60-80
2-3
Polybenzimidazole
1.4-1.41
10-15
30-50
10-20
60-80
40-45
10-15
Polyoxadiazole (Arselon) 1.43-1.44
20-55
50-90
4-8
50-60
75-90
3-8
Polyamide benzimidosol
(benzimidazole)
1.43-1.45
–
40-60
10-15
–
–
10-15
Ladder (BBB, Lоlа)
1.40-1.59
30-45
35-45
3-6
70-85
80-95
2-3
Source: compiled by the authors
The elaboration of aramid threads, based on the Rusar aromatic copolymers that
are produced on an industrial scale in SPE Termotex (Russia), deserves special
attention (see tab. 3).
Table 3 The main characteristics of the Rusar threads
Indicators
Thread mark
Rusar
Rusar-C
Rusar-NT
Rusar-K
Breaking point of thread in microplastic, GPa
5.0
5.4
5.2
4.6
Initial modulus of elasticity at
stretching,
GPa:
- static
- dynamic
1.35
1.45
1.6
1.7
1.8
2.0
1.65
1.8
Oxygen index, %
35
35
45
48
Water retention, %
3.3
2.25
1.35
1.32
Elongation at fracture, %
3.3
2.6
2.6
2.4
Density, g/cm
3
1.45
1.46
1.47
1.45
Long-term creep, %
0.3
0.096
0.1
–
Source: compiled by the authors
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