Blend irregularity and migratory behaviour of blend constituents in AJS polyester-viscose yarns

Abstract

Image analyzer has been used to study the effect of blend percentage on blend irregularity both in the cross -section and on the surface of polyester- viscose blended air-jet spun yarn. This method is rapid and precise enough to determine zone wise number distribution of the blend constituents in yarn cross-section. Within and between zone variance and index of blend irregularity values are derived which reflect the extent of blend irregularity for blowroom and drawframe blended yarns. The above parameters are minimum for polyester-viscose (67:33) blowroom blended yarns and higher for extreme blends. Migratory behaviour of polyester and viscose fibres with the change in blend proportion has also been studied using tracer fibres. Migratory behaviour of fibers is found to get influenced by blend proportion apart from the intrinsic characteristics of fibres. In the blended yarns, viscose component migrates from core to surface. Polyester-rich blended yarn possesses maximum wraps/mm and cork-screw type of structure.