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| Weatherability |
| Silicone rubbers have exceptional weatherability. Ozone created by corona discharge rapidly deteriorates most organic rubbers,but has almost no effect on silicone rubber. In addition, silicone rubber can be exposed to wind, rain and UV rays for long periods with virtually no change in its physical properties. |
| Results of long-term outdoor exposure testing of various rubbers |
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| Deterioration conditions |
Time until surface cracks are first apparent (years) |
Time of sunlight exposure until elongation is 1/2 that of the initial value (years) |
| Location |
Panama |
Rock Island |
Panama |
Rock Island |
| Rubber type |
| Styrene butadiene |
2-3.5 |
Over 10years |
4 |
10 |
| Nitrile |
0.5-1 |
- |
7 |
10 |
| Chloroprene |
- |
- |
8.5 |
Over 10years |
silicone
(methy vinyl) |
Over 10years |
Over 10years |
Over 10years |
Over 10yearsto decline to 75% |
| Silicone (methylphenyl) |
- |
- |
Over 10years |
Over 10years |
| Fluorosilicone |
- |
- |
0.5 |
4 |
| Ethylene propylene |
- |
- |
10 |
over 10 years to decline to 90% |
| Fluorine |
10 |
10 |
over 10years to decline to 90% |
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