OPTOTHERMAL PROPERTIES OF FIBERS .10. TEMPERATURE-DEPENDENCE OF THE SKIN-CORE STRUCTURE OF NYLON-6 FIBERS

Refractive indices and birefringence for skin and core changes with an nealing, produced by different annealing conditions in nylon-6 fibers, were measured interferometrically. Applications were carried out usin g multiple-beam Fizeau fringes in transmission to determine Cauchy's c onstants and dispersive coefficients for the fibers. The resulting dat a were used to calculate the polarizability per unit volume for each l ayer. By optical microscopy, the geometrical parameters of the fiber c ross section were found. The effect of temperature and time of anneali ng on the refractive index and birefringence for each layer were also investigated. The relationships between temperature and time of anneal ing with the optical parameters were drawn. Illustrations are given us ing microinterferograms and curves. (C) 1997 John Wiley & Sons, Inc.