Theoretical analysis of the interfacial-shear-stress induced delamination of polymeric coatings from the glass fibers in double-coated optical fibers during temperature cycling

摘要

To prevent the delamination of polymeric coatings from glass fibers, temperature cycling induced interfacial-shear-stress between the glass fiber and primary coating should be always smaller than its interfacial shear strength in a long time. The method for the prevention of the long-term delamination of polymeric coatings from glass fibers is as follows. The thickness of the primary coating can be increased if the spring constant of the optical fiber is selected to prevent low temperature microbending of the glass fiber. Meanwhile, Poisson's ratio of the primary coating should be selected to be very close to 0.5. Alternatively, the relaxation time of the primary coating and secondary coating should be increased, but Young's modulus of the primary coating as well as the thermal expansion coefficient of the secondary coating should be decreased. Meanwhile, the thickness and Young's modulus of the secondary coating should be decreased if the strength of the secondary coating is satisfied.