Solid-State Co-Extrusion of Nylon 6 Gel.

A partially dried Nylon 6 gel has been drawn at 150 C and to draw ratio 5.7X, by a split billet co-extrusion technique in an Instron capillary rheometer. The gel was prepared by dissolving Nylon 6 in benzyl alcohol at 165 C and cooled to gel at room temperature. On removing solvent, preorientation was introduced into the gel with the b-chain axis weakly oriented perpendicular to the gel surface. Drawing produces double orientation as shown by wide-angle x-ray diffraction. One population of the crystals are oriented with chain axes in the draw direction, as in the usual uniaxial drawing. The second population have their chain axes oriented perpendicular to draw direction. From birefringence, wide- and small-angle x-ray scattering studies, a deformation mechanism for the double orientation was proposed. Thermal and mechanical properties were also studied. Annealing at 190 C produced partial reorientation of the second crystals resulting in a more complex orientation.