Influence of thermal treatment on properties of friction-spun core yarns

295-300The influence of proportion of sheath content and thermal treatment under the relaxed condition on thermal shrinkage, sheath-slipping resistance and tensile properties of DREF-III friction-spun core yarns made of polyester multifilament core and cotton sheath has been studied both in dry and wet state. It is observed that the thermal treatment markedly increases the thermal shrinkage and sheath-slipping resistance. The sheath-slipping resistance of wet treated yarns is found to be higher than that of dry treated yarns. Breaking elongation increases with the increase in treatment temperature. The increase in proportion of sheath fibre content decreases the thermal shrinkage and increases the sheath-slipping resistance and breaking strength