In present study, rheological properties of polypropylene impact copolymer (PPcp) and polyolefin elastomer (POE) blend melts were evaluated on a capillary rheometer under shear and elongational flows. The flow and melt elastic properties (die swell and first normal stress difference) studied at varied extrusion conditions were correlated with blend morphology and elastomer content by means of image analysis and theoretical models. Dispersed particle break-up and coalescence were observed to be influenced by POE content and the viscosities of the constituent polymers which were in turn affected by the capillary extrusion conditions (shear rate in particular). The blend melts demonstrated typical pseudoplastic behavior obeying Cross model under shear flow. The elongational flow also corroborated well with the shear flow behavior. All the blends illustrated prominent dependence of melt elastic properties on POE content and the capillary extrusion conditions. The melt elastic properties were also found to critically rely on the inter-particle distance of the POE phase.

在本研究中，聚丙烯抗冲共聚物 (PPcp) 和聚烯烃弹性体 (POE) 共混物熔体的流变性能在毛细管流变仪上在剪切流和伸长流下进行评估。通过图像分析和理论模型，在不同挤出条件下研究的流动和熔体弹性特性（模具膨胀和第一法向应力差）与共混物形态和弹性体含量相关联。观察到分散的颗粒破碎和聚结受 POE 含量和组成聚合物的粘度的影响，而这些聚合物的粘度又受毛细管挤出条件（特别是剪切速率）的影响。共混物熔体在剪切流下表现出典型的假塑性行为，遵循 Cross 模型。伸长流动也很好地证实了剪切流动行为。所有共混物都表明熔体弹性性能对 POE 含量和毛细管挤出条件的显着依赖性。还发现熔体弹性性能严重依赖于 POE 相的颗粒间距离。