Migratory behaviour of core and sheath fibres in dref-III friction-spun acrylic yarns

Abstract

The migratory behaviour of core and sheath fibres in dref-III friction-spun yarns has been studied using the tracer fibre technique. It is observed that the fibre migration in these yarns is restricted to particular zones only, depending on the position of fibre feed. Core fibres exhibit minimum values of migration parameters. In sheath, the fibres fed nearer to the

delivery end show comparatively larger values. The two streams seem to be interlacing in the radial zone of 0.2-0.4. An increase in suction pressure decreases the fibre migration in both core and sheath elements while a decrease in core content initially decreases it, followed by an increase. Further, the variations in yarn tenacity and breaking extension have also been

explained in terms of these changes in migration parameters.