Optothermal properties of fibers. IV. Optical properties of nylon 66 fibers as a function of quenching process

Abstract

In this work, optical properties of samples of nylon 66 fibers were quenched in coarse-grained ice after annealing in the temperature range 80-180°C for 1-10 h. Two independent techniques were used to study optical parameters in these fibers. The first technique is the application of the diffraction technique to study the effect of quenching on the swelling factors of these fibers for some different liquids at room temperature of 25 ± 1°C. The second method dealt with the application of multiple-beam Fizeau fringes in transmission to estimate the refractive indices and birefringence of the skin and core of these fibers. The obtained results were utilized to calculate the polarizability per unit volume, isotropic refractive indices, and the Cauchy's dispersion constants. The relationship between n s ∥ , ⊥, n c ∥ , ⊥, n a ∥ , ⊥, Δn s , Δn c , Δn a , n (iso)s , n (iso)c , and n (iso)a and different annealing times and temperatures is given for these fibers. Microinterferograms and curves are also given.