iPP/EPR共混物的动态流变行为与相容性

Dynamic Rheological Behavior and Miscibility of iPP/EPR Blends

使用旋转流变仪研究了等规聚丙烯（iPP）／乙烯-丙烯无规共聚物（EPR）共混物在熔融状态下的动态流变行为，探讨了共混物的动态流变行为随EPR的质量分数、温度以及角频率的变化规律，分析了共混物的相容性。结果表明：随着角频率的增加，iPP，EPR以及iPP／EPR共混物熔体的复数黏度呈下降趋势，呈现出假塑性流体的剪切变稀行为。iPP／EPR共混物的零剪切黏度随着EPR加入量的变化出现了正-负偏差，曲线呈S形。当EPR的质量分数小于18％时，零剪切黏度出现负偏差，而当EPR的质量分数在18％～30％时出现正偏差。不同温度下的iPP／EPR共混物熔体为均相结构，iPP与EPR之间具有一定的相容性。

The dynamic rheological behavior of isotactic polypropylene (iPP)/ethylene-propylene random copolymer (EPR)blends was investigated by rotational rheometer under the molten state. The effects of the mass fraction of EPR,temperature and angular frequency on the dynamic rheo-logical behavior of the blends were discussed,and the melting miscibility was analyzed.The re-sults show that the complex viscosities of the melt of iPP,EPR and the blends reduce with the angular frequency increasing,indicating of shear-thinning behavior of pseudoplastic fluid.The varia-tion of zero shear viscosity of iPP/EPR blends shows positive-negative devitions with the mass fraction of EPR increasing and the viscosity-composition curve reveals an S shape.The zero shear viscosity shows negative deviation when the mass fraction of EPR is less than 18%,whereas the positive deviation occurs when the mass fraction of EPR is 18%~30%.The melt of iPP/EPR blends at different temperatures is all homogeneous,which means that they have good miscibility.