再生聚酯切片生产缝纫线用涤纶短纤维的工艺研究

Production process of polyester staple fibers for sewing thread using regenerated polyester chips

以物理法再生聚对苯二甲酸乙二醇酯(PET)切片为原料,通过纺丝-拉伸法制备涤纶拉伸丝,从切片的外观特点、过滤性能、特性黏数及流变性能,以及拉伸丝的性能考察原料的可纺性及相应的纺丝、拉伸工艺要求;在此基础上以再生PET切片为原料,在现有常规涤纶短纤维间接纺生产线上生产缝纫线用再生涤纶短纤维,探讨了其生产工艺条件。结果表明:粒子形状规整、过滤性能较好、特性黏数较高的再生PET切片具有良好的可纺性,纺丝过程中需根据切片的特性黏数调整纺丝温度,拉伸过程中需适当提高拉伸温度;采用特性黏数为0.737 dL/g的再生PET切片为原料生产1.33 dtex×38 mm缝纫线用再生涤纶短纤维,与以原生PET切片为原料相比,螺杆熔融温度提高8℃,箱体温度提高5℃,拉伸温度和定型温度分别提高3~5℃;通过生产调控,生产稳定性好,生产的短纤维断裂强度达到6.1 cN/dtex,其他质量指标达到原生涤纶短纤维优等品要求。

Using regenerated polyethylene terephthalate(PET)chips by physical method as raw material,polyester drawn fiber was prepared by spinning-drawing method.The spinnability of regenerated PET chips and the corresponding spinning and drawing process requirements were investigated based on the appearance characteristics,filtration performance,intrinsic viscosity and rheological properties of chips and the properties of drawn fibers.On this basis,the regenerated PET chips were used as raw material to produce regenerated polyester staple fibers for sewing threads on an existing conventional polyester staple fiber indirect spinning production line,and the production process conditions were discussed.The results showed that the regenerated PET chips had good spinnability due to their regular particle shape,good filtration performance and high intrinsic viscosity,and the spinning temperature needs to be adjusted according to the intrinsic viscosity of the chips during the spinning process,and the drawing temperature needs to be appropriately increased during the drawing process;a regenerated PET chip with an intrinsic viscosity of 0.737 dL/g was used as raw material to produce 1.33 dtex×38 mm regenerated polyester staple fiber for sewing thread,and as compared with those of primary PET chips,the screw melting temperature was increased by 8℃,the box temperature by 5℃,and the drawing temperature and setting temperature by 3-5℃,respectively;and the production was stable,the breaking strength of the produced staple fiber reached 6.1 cN/dtex,and other quality indicators met the requirements of high-quality raw polyester staple fibers after production regulation.