Fiber coating interactions with buffer tube gels

Significant degradation of the fiber coatings occurred in an optical fiber cable that was aged for five days at 85°C. Incompatibility between the coating and the surrounding buffer tube gel was the suspected cause. To investigate this problem, fiber samples were aged in several gels, the compositions of which were determined using a variety of analytical techniques. Coating degradation occurred as cracking or discoloration in all but one of the gels. These degradations were found to have a strong temperature dependence and to be closely related to the molecular weight distributions of the gel components. Compatibility screening was identified as a necessary procedure to avoid future recurrences of this problem