熔体直纺83 dtex/36 f异形全消光涤纶拉伸丝生产工艺优化

Optimization of production process of 83 dtex/36 f profiled full dull polyester drawn yarn by melt direct spinning

采用熔体直纺及在线添加全消光母粒技术生产83 dtex/36 f异形全消光涤纶拉伸丝,针对生产中断头和毛丝多的问题,对全消光母粒的干燥及熔融挤出工艺、纺丝及拉伸定形工艺等进行了优化。结果表明:控制干燥温度145℃、干燥时间12 h,干燥后全消光母粒含水率低于30μg/g;母粒熔融挤出时螺杆各区温度采取温度逐步递增的方式,可减少熔体黏度降;控制熔体输送管道温度283℃,纺丝箱体温度292℃,无风区高度60 mm,侧吹风速度0.55 m/s,拉伸温度72℃,热定形温度140℃,一级拉伸倍数1.1,二级拉伸倍数1.92,卷绕速度4500 m/min,可纺性好;在上述工艺条件下,生产中断头和毛丝数量大幅降低,生产稳定性大幅提高,产品质量达到FZ/T 54105—2018《全消光涤纶拉伸丝》规定的优等品等级,纤维断裂强度3.71 cN/dtex、断裂伸长率29.8%,纤维中二氧化钛质量分数2.1%。

A 83 dtex/36 f profiled full dull polyester drawn yarn was prepared by melt direct spinning and online full dull masterbatch addition technology.The drying and melt extrusion of full dull masterbatch,spinning and drawing formation process were optimized to solve the problems of broken ends and fuzziness in production.The results showed that the moisture content of full dull masterbatch was lower than 30μg/g after drying at 145℃for 12 h;the temperature increasing patterns in each area of the screw could reduce the melt viscosity drop during the melting and extrusion of masterbatch;the spinnability was satisfying when the process conditions were as followed:melt conveying pipeline temperature 283℃,spinning box temperature 292℃,calm zone height 60 mm,cross air blow speed 0.55 m/s,drawing temperature 72℃,heat setting temperature 140℃,first draw ratio 1.1,second draw ratio 1.92 and winding speed 4500 m/min;and the broken ends and fuzziness were considerably depressed,the production stability was greatly improved,and the product quality met the superior grade specified in FZ/T 54105-2018 Full Dull Polyester Drawn Yarn,with a breaking strength of 3.71 cN/dtex,elongation at break of 29.8%and 2.1%titanium dioxide in the fiber by mass fraction under the above process conditions.