聚对苯二甲酸-丁二酸丁二醇酯流变性能及复合纺丝工艺研究

Study on rheological behavior and composite spinning process of poly(butylene succinate-co-terephthalate)

本文采用毛细管流变仪研究了聚对苯二甲酸-丁二酸丁二醇酯(PBST)和聚对苯二甲酸丁二酯(PBT)流变性能,分析两种熔体在不同剪切速率和温度下动力黏度及匹配度。在动力黏度匹配较好的工艺下,对PBT和PBST进行并列复合纺丝,并牵伸,评价纤维卷曲性能。结果表明:PBST共聚酯非牛顿指数较小,表观黏度受剪切速率的影响较PBT大。两种熔体的结构程度及两者结构化程度的差异均随着温度的升高而减小,说明升高温度可提高复合可纺性。PBST共聚酯黏流活化能受剪切速率的影响较PBT小。复合纤维最佳纺丝工艺:PBST与PBT质量比为5:5,PBST螺杆进料温度210℃,PBT螺杆进料温度255℃,纺丝箱体温255℃,牵伸温度85℃,制备的纤维具有很好的自卷曲性能。

Therheological behavior of poly(butylene succinate-co-terephthalate)(PBST)and poly butylene terephthalate(PBT)were studied by capillary rheometer in the research.The side-by-side composite spinning process conditions were optimized based on the shearing rate at spinneret nozzle outlets and the apparent viscosity of PBST and PBT melts at different temperature.The crimp property of the fiber was also studied.The results showed that the non-Newtonian index of PBST was smaller,and apparent viscosity was more sensitive to shear rate than PBT.The structural degree of the two melts and the difference of their structural degree decreased with the increase of temperature,which showed that the spinnability of the composite could be improved by increasing the temperature.The viscous flow activation energy of PBST was less sensitive to shear rate than PBT.The spinning process conditions were optimized as followed:m(PBST):m(PBT)at 5:5,screw temperature 210℃for PBST and 255℃for PBT,spinning manifold temperature 293℃,drawing temperature 85℃,and the fiber had good self-crimping property.