不同聚乳酸切片的流变性能比较及其对熔融纺丝性能的影响研究

摘要

A comparison study on rheological properties of four poly(lactic acid) chips were measured by capillary rheometer, and their effects on melt spinning performance were discussed.The results indicated that: the four kinds of poly(lactic acid) melt showed shear-thinning, having non-Newtonian fluid flow characteristics;as the temperature increased, the poly(lactic acid) melts` non-Newtonian index increased;the poly(lactic acid) melts` viscons flow activation energy were small and had a small change in viscosity with temperatures, which was conductive to spinning molding;the poly(lactic acid) melts` structural viscosity index were between 0.8 to 1.4, showed a better spinning and stability.%利用毛细管流变仪对四种不同聚乳酸切片的流变行为进行了对比分析,并探讨了流变性能差异对熔融纺丝性能的影响.结果表明:四种聚乳酸熔体均呈现剪切变稀现象,具有非牛顿流体的流动特征;随着温度升高,聚乳酸熔体的非牛顿指数n增大;四种聚乳酸熔体的粘流活化能Eη较小,粘度随温度的变化小,有利于纺丝成型;四种聚乳酸熔体的结构粘度指数△η介于0.8~1.4,可纺性和稳定性较好.