10.62 |
SECTION 10 |
Styrene-butadiene rubber (SBR) is also known as government rubber styrene (GRS) and Buna S.
10.4.16Urethane
See Table 10.3.
TABLE 10.3 |
Properties |
of Natural |
and |
Synthetic |
|
Rubbers |
|
|
|
|
|
|||||||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Durometer |
Ultimate |
||
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Specific |
hardness |
elongation |
||
|
|
|
|
|
|
Rubber |
|
|
|
|
|
|
|
gravity |
(or Shore) |
% (23 C) |
||
Gutta |
percha |
(hard |
rubber) |
|
|
|
|
|
|
|
1.2–1.95 |
(65–95) |
3 |
–8 |
||||
Natural |
|
rubber |
|
(NR) |
|
|
|
|
|
|
|
|
0.93 |
20–100 |
750–850 |
|||
Chlorosulfonated |
|
polyethylene |
|
|
|
|
|
|
|
1.10 |
50–95 |
100 |
–500 |
|||||
Epichlorohydrin |
|
|
|
|
|
|
|
|
|
|
|
1.27 |
60–90 |
100 |
–400 |
|||
Fluoroelastomers |
|
|
|
|
|
|
|
|
|
|
|
1.4–1.95 |
60–90 |
100 |
–350 |
|||
Isobutene-isoprene |
|
|
rubber |
(IIR) |
[also |
known |
a s |
|
|
|
|
|
|
750–950 |
||||
government |
|
rubber |
I(GR-I)] |
|
|
|
|
|
|
|
0.91 |
(40–70) |
||||||
Nitrile |
rubber |
|
(butadiene-acrylonitrile |
|
rubber) |
(also |
|
|
|
|
|
|
–600 |
|||||
known |
a s |
B |
una |
N and |
NBR) |
|
|
|
|
|
|
|
1.00 |
30 |
–100 |
100 |
||
Polyacrylate |
|
|
|
|
|
|
|
|
|
|
|
|
1.10 |
40–100 |
100 |
–400 |
||
Polybutadiene |
|
rubber |
(BR) |
|
|
|
|
|
|
|
0.93 |
30 |
–100 |
100 |
–700 |
|||
Polychloroprene |
|
(neoprene) |
|
|
|
|
|
|
|
1.23 |
20 |
–90 |
800–1000 |
|||||
Poly(ethylene-propylene-diene) |
|
(EPDM) |
|
|
|
|
|
|
0.85 |
30 |
–100 |
100 |
–300 |
|||||
Polyisobutylene |
|
(butyl |
rubber) |
|
|
|
|
|
|
|
0.92 |
30 |
–100 |
100 |
–700 |
|||
Polyisoprene |
|
|
|
|
|
|
|
|
|
|
|
|
0.94 |
20 |
–100 |
100 |
–750 |
|
Polysulfide |
(Thiokol |
ST) |
|
|
|
|
|
|
|
1.34 |
20 |
–80 |
100 |
–400 |
||||
Poly(vinyl |
chloride) |
(Koroseal) |
|
|
|
|
|
|
|
1.32 |
(80–90) |
|
|
|||||
Silicone, |
|
high-temperature |
|
|
|
|
|
|
|
|
|
|
|
50–800 |
||||
Silicone |
|
|
|
|
|
|
|
|
|
|
|
|
|
0.98 |
20–95 |
|||
Styrene-butadiene |
|
|
rubber |
(SBR) |
(also |
known |
a s |
B |
una |
S) |
0.94 |
40–100 |
400–600 |
|||||
Urethane |
|
|
|
|
|
|
|
|
|
|
|
|
|
0.85 |
62–95 |
100–700 |
||
Tensile |
|
|
strength, |
||
lb ·in |
2 |
(23 C) |
|
||
4000–10,000 |
||
3000 |
–4500 |
|
500–3000 |
||
1000 |
–2500 |
|
2000 |
–3000 |
|
2300–3000 |
||
500–4000 |
||
1000 |
–2200 |
|
2500–3000 |
||
2000 |
–3500 |
|
1000 |
–3000 |
|
1000 |
–3000 |
|
2000–3000 |
||
700–1250 |
||
2400–3000 |
||
700–800 |
||
500–1500 |
||
1600–3700 |
||
1000–8000 |
||
Service |
|
temperature, |
C |
Minimum |
Maximum |
|
104 |
56 |
82 |
54 |
121 |
46 |
121 |
40 |
232 |
|
121 |
54 |
121 |
18 |
149 |
62 |
79–100 |
54 |
121 |
40 |
149 |
54 |
100 |
54 |
79–82 |
54 |
82–100 |
|
71 |
|
316 |
84 |
232 |
60 |
107 |
54 |
100 |
63.10