Optical and structural properties of nylon 6 fibres exposed to UV radiation

Nylon 6 fibres irradiated in air by a UV source were examined by a two-beam polarizing interference microscope. Refractive indices and birefringence values were obtained experimentally and compared with those of unirradiated samples. The experimental measurements were used to calculate some optical and structural parameters. Polarizabilities per unit volume, isotropic and virtual refractive indices, orientation function and angle, degree of crystallinity, molar refractivity and specific refractivity of the dielectric were among the calculated parameters. The effect of UV radiation on the refractive indices along the diameter, and related parameters were investigated. Relationships between optical and structural parameters and their changes with the exposure time are discussed. The study shows that new reorientation occurred as a result of radiation.