Comparison Of Cotton/Polyurethane Elastic Rotor Spun Yarn And Ring Spun Yarn

At present the cotton/polyurethane elastic yarn is mainly produced by the method of ring spinning. However, ring spinning has a lot of weakness such as low efficiency, complex technology and long flow etc, so people attempt to use new-type spinning to produce the composite yarn. New-type spinning has unique superiority such as short flow, high efficiency and big volume etc. The rotor spinning has become one of the most quickly developed new-type spinning. In recent years, the study of rotor spun composite yarn has begun in our country. The process, property and structure of cotton/polyurethane elastic rotor spun yarn are compared with those of cotton/polyurethane elastic ring spun yarn in this article.Firstly, the effect of ring speed, twist factor and the draw ratio of filament on the property of cotton/polyurethane elastic ring spun yarn is analyzed. The optimum parameters are obtained using the orthogonal design theory. For the 61tex cotton/polyurethane elastic ring spun yarn, the optimized ring speed is 12000r/min, twist factor is 330 and draw ratio is 3.63. For the 39tex cotton/polyurethane elastc ring spun yarn, the optimized ring speed is 12000r/min, twist factor is 370 and draw ratio is 3.5.Secondly, the process of elastic rotor spun yarn and ring spun yarn are compared. The results indicate that the relationship between the property of elastic rotor spun yarn and the processing parameters is similar with that of elastic ring spun yarn. With the increase of the twist factor, the strength of elastic yarn increases first and then goes down. The elongation, evenness and hairiness decrease gradually as the twist factor increases. The elongation of elastic yarn increases first and then goes down with the increase of the draw ratio of polyurethane filament, while the strength, evenness and hairiness of elastic yarn keep increasing. There are also some differences between elastic rotor spun yarn and elastic ring spun yarn. The strength, evenness and hairiness of elastic rotor spun yarn are lower than those of elastic ring spun yarn while the elongation is higher than that of elastic ring spun yarn.Thirdly, 61tex and 39tex elastic rotor spun yarn and ring spun yarn spun with the optimum spinning parameters. In addition, a series of elastic rotor spun yarn and elastic ring spun yarn with the same linear density were spun. The difference of property of elastic rotor spun yarn and elastic ring spun yarn is studied. The strength of elastic rotor spun yarn is lower than that of elastic ring spun yarn by 10～15%, the elongation is higher than that of elastic ring spun yarn for about 30～40%, the evenness is lower than that of elastic ring spun yarn's by 10～25%, the hairness is lower than that of elastic ring spun yarn by 75～80%, the elastic recovery is higher than that of elastic ring spun yarn by 10～15%.Fourthly, the difference of structure of elastic rotor spun yarn and ring spun yarn spun with the optimum spinning parameters is studied using the method of scanning electron microscopy and the method of immerging of liquor. The results indicate that the structure of elastic rotor spun yarn is that the staple yarn wraps around the filament, while the structure of elastic ring spun yarn is that cotton fibre covers the filament.Finally, the strength and elasticity of the elastic yarn were predicted using adaptive neural-network-based fuzzy inference system (ANFIS). The predictive models show that the strength and elasticity of the elastic yarn have nonlinear relationship with twist factor, draw ratio of filament and linear density.