PYROCOAT® K: Industry-Leading Thermal Stability

OFS is the market leader of optical fibers designed for applications beyond traditional telecommunications uses. These include harsh environments where fibers are exposed to extremes in temperature, aggressive chemicals, and challenging mechanical requirements.

PYROCOAT K coated optical fibers are designed for harsh temperature sensing and communications environments.  This thin, hard polymer coating provides mechanically strong fiber with excellent chemical resistance, small cross-section, and industry-leading long-term high-temperature exposure.  PYROCOAT K provides excellent thermal stability offering higher operating temperatures than other commercially available polymer coated fibers.  Touting continuous lifetime temperatures of 275 °C for up to 80 years, 300 °C for up to 13 years, 325 °C for up to 2.2 years, these new fibers can also withstand short-term (24 hours) excursions as high as 450 °C.

   Commcercially Available Polyimide-Coated Fibers
 Lifetime at 275 °C
4 years
80 years
 Lifetime at 300 °C  0.8 years
 13 years
 Lifetime at 325 °C  70 days
 2.2 years
 Lifetime at 350 °C  18 days
 160 days
 20-year Continuous Upper Use Temperature
250 °C
293 °C
Fiber/Metal Interaction at 300 °C
Fiber sticks to metal
Fiber does not stick to metal
Aging in distilled water, 200 °C, 2000 psi, 7 days
Coating material degrades
No coating degradation
Aging in sea water, 100 °C, 2000 psi, 14 days  No coating degradation  No coating degradation
Aging in mineral oil, 250 °C, 2000 psi, 10 days 
 No coating degradation  No coating degradation
Aging in isopropanol, 250 °C, 1500 psi, 7 days 
 No coating degradation No coating degradation

 NOTE: The lifetimes are based on 25% loss of the initial coating mass criterion. For details, please see A. A. Stolov, D. A. Simoff, J. Li, Thermal Stability of Specialty Optical Fibers, J. Lightwave Technol., 2008, V 26, N 20, P. 3443-3451



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