Texturing of Polyester-Viscose Blended Yarn by Batch and Continuous Processes

Abstract

Union-setting (combined heat-setting and resin-curing) of polyester-viscose blended yarns of varying blend ratios (20/80, 50/50, 65/35, and 80/20) was studied for producing textured yarn by batch (twist-set-detwist) and continuous (false-twist) methods. Basic aluminum chloride and magnesium dihydrogen phosphate were used as catalysts for the setting of the viscose component by dimethylol dihydroxyethylene urea. In the batch process an increase in the curing time from 2.5 to 30 seconds marginally increases the extent of resin fixation with no concommitant increase in the crimp rigidity. The crimp rigidity, however, increases with increase in the polyester component in the blend. The ratios of wet/dry retractability and wet/dry tenacity are maximum in 65/35 polyester-viscose blended yarn. Continuous false-twist texturization of blended yarn with simultaneous setting of both the components was possible even with a residence time of 1 second in the heater.