Reconstructing some physical characteristics due to cold drawing process for nylon 6 fibres

This work reports measurement of the molecular orientation by two technique s in two samples of (Egyptian manufacturer) nylon 6 fibres drawn at room te mperature. The changes in the strain were evaluated to obtain the shrink ag e stress and the mechanical orientation factors [P-2 (cos theta)] and [P-4 (cos theta)]. The resultant optical parameters, obtained by interferometry, were used to calculate the isotropic and virtual refractive indices acid t he various orientation functions f(Delta) (theta), f(2) (theta), f(4) (thet a) and f(6) (theta). Also calculation of the polarizability factor (Delta a lpha /3 alpha (o)), dielectric constants, dielectric susceptibility, number N-1 of a random links between the network junction points per unit volume, number N-c of chains per unit volume, average work per chain w', number N- m of molecules per unit volume, surface reflectivity and other parameters w ere calculated. Relationships between the calculated parameters and the dra w ratios were given. An empirical formula was suggested to correlate change s in the evaluated parameters with different draw ratios and its constants were determined. The present study demonstrates changes in the molecular re orientation factors and structural parameters. (C) 2001 Elsevier Science Lt d. All rights reserved.