355 dtex/72 f纺前着色六叶形预取向丝的生产工艺初探

Production Process of Dyeing Before Spinning 355 dtex/72 f Six-Leaf POY

采用熔体直纺在线注射的工艺路线,对355 dtex/72 f六叶形松枝绿预取向丝(POY)的纺丝工艺进行了探索。生产实践表明:熔体应采用先冷却后增压再冷却的输送方式,其特性黏度应略偏高,同时DEG和TiO2的含量不能太高;色母粒的干燥和注射工艺条件是干燥热空气的露点低于-90℃,干燥温度为155℃,停留时间控制在7 h左右,干燥以后的色母粒含水率在3.5×10^-5以下;螺杆挤压机直接将熔融色母粒注入熔体后以动态混合的方式纺丝,母粒质量分数为2.6%。异形喷丝板直径88 mm,孔数为72,喷丝孔采用菱形10行对称交错分布的方式;每个微孔相邻的叶之间的角度均为60°,叶宽为0.13 mm,叶长为0.7 mm,叶高为1.1 mm。实际生产中,箱体温度284~286℃,冷却风速0.55~0.60 m/s,上油率0.40%~0.45%,卷绕速度2800~2900 m/min,分段控制接触压力、卷绕角可以获得较好的成型,POY退绕良好。

The process route of melt direct spinning and on-line injection was adopted, and the spinning technology of 355 dtex/72 f six-leaf pine branch green pre-oriented yarn(POY) is explored. Production practice shows that the melt should be cooled first, then pressurized and then cooled, its intrinsic viscosity should be slightly higher, and the content of DEG and TiO2 should not be too high. The drying and injection conditions of color masterbatch are as follows: the dew point of hot air is lower than-90 ℃, the drying temperature is 155 ℃, the residence time is about 7 hours, and the moisture content of the dried masterbatch is below 3.5×10^-5. The melt masterbatch is directly injected into the melt and then dynamically mixed by a screw machine. The masterbatch content is 2.6%. The diameter of the special-shaped micro hole spinneret is 88 mm, and the number of holes is 72. The spinneret holes are arranged symmetrically in 10 rows of diamond. The angle between the leaves adjacent to each pore is 60 degrees, the leaf width is 0.13 mm, the leaf length is 0.7 mm, and the leaf height is 1.1 mm. In the actual production, the box temperature is 284~286 ℃, the cooling wind speed is 0.55~0.60 m/s, the oil loading rate is 0.40%~0.45%, the winding speed is2 800~2 900 m/min, the sectional control of contact pressure and winding angle can obtain good molding,and the POY unwinding is good.